/*
* @(#)ObjectInputStream.java 1.155 04/05/28
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.io;
import java.lang.reflect.Array;
import java.lang.reflect.Modifier;
import java.lang.reflect.Proxy;
import java.security.AccessController;
import java.security.PrivilegedAction;
import java.util.Arrays;
import java.util.HashMap;
import sun.misc.SoftCache;
/**
* An ObjectInputStream deserializes primitive data and objects previously
* written using an ObjectOutputStream.
*
* <p>ObjectOutputStream and ObjectInputStream can provide an application with
* persistent storage for graphs of objects when used with a FileOutputStream
* and FileInputStream respectively. ObjectInputStream is used to recover
* those objects previously serialized. Other uses include passing objects
* between hosts using a socket stream or for marshaling and unmarshaling
* arguments and parameters in a remote communication system.
*
* <p>ObjectInputStream ensures that the types of all objects in the graph
* created from the stream match the classes present in the Java Virtual
* Machine. Classes are loaded as required using the standard mechanisms.
*
* <p>Only objects that support the java.io.Serializable or
* java.io.Externalizable interface can be read from streams.
*
* <p>The method <code>readObject</code> is used to read an object from the
* stream. Java's safe casting should be used to get the desired type. In
* Java, strings and arrays are objects and are treated as objects during
* serialization. When read they need to be cast to the expected type.
*
* <p>Primitive data types can be read from the stream using the appropriate
* method on DataInput.
*
* <p>The default deserialization mechanism for objects restores the contents
* of each field to the value and type it had when it was written. Fields
* declared as transient or static are ignored by the deserialization process.
* References to other objects cause those objects to be read from the stream
* as necessary. Graphs of objects are restored correctly using a reference
* sharing mechanism. New objects are always allocated when deserializing,
* which prevents existing objects from being overwritten.
*
* <p>Reading an object is analogous to running the constructors of a new
* object. Memory is allocated for the object and initialized to zero (NULL).
* No-arg constructors are invoked for the non-serializable classes and then
* the fields of the serializable classes are restored from the stream starting
* with the serializable class closest to java.lang.object and finishing with
* the object's most specific class.
*
* <p>For example to read from a stream as written by the example in
* ObjectOutputStream:
* <br>
* <pre>
* FileInputStream fis = new FileInputStream("t.tmp");
* ObjectInputStream ois = new ObjectInputStream(fis);
*
* int i = ois.readInt();
* String today = (String) ois.readObject();
* Date date = (Date) ois.readObject();
*
* ois.close();
* </pre>
*
* <p>Classes control how they are serialized by implementing either the
* java.io.Serializable or java.io.Externalizable interfaces.
*
* <p>Implementing the Serializable interface allows object serialization to
* save and restore the entire state of the object and it allows classes to
* evolve between the time the stream is written and the time it is read. It
* automatically traverses references between objects, saving and restoring
* entire graphs.
*
* <p>Serializable classes that require special handling during the
* serialization and deserialization process should implement the following
* methods:<p>
*
* <pre>
* private void writeObject(java.io.ObjectOutputStream stream)
* throws IOException;
* private void readObject(java.io.ObjectInputStream stream)
* throws IOException, ClassNotFoundException;
* private void readObjectNoData()
* throws ObjectStreamException;
* </pre>
*
* <p>The readObject method is responsible for reading and restoring the state
* of the object for its particular class using data written to the stream by
* the corresponding writeObject method. The method does not need to concern
* itself with the state belonging to its superclasses or subclasses. State is
* restored by reading data from the ObjectInputStream for the individual
* fields and making assignments to the appropriate fields of the object.
* Reading primitive data types is supported by DataInput.
*
* <p>Any attempt to read object data which exceeds the boundaries of the
* custom data written by the corresponding writeObject method will cause an
* OptionalDataException to be thrown with an eof field value of true.
* Non-object reads which exceed the end of the allotted data will reflect the
* end of data in the same way that they would indicate the end of the stream:
* bytewise reads will return -1 as the byte read or number of bytes read, and
* primitive reads will throw EOFExceptions. If there is no corresponding
* writeObject method, then the end of default serialized data marks the end of
* the allotted data.
*
* <p>Primitive and object read calls issued from within a readExternal method
* behave in the same manner--if the stream is already positioned at the end of
* data written by the corresponding writeExternal method, object reads will
* throw OptionalDataExceptions with eof set to true, bytewise reads will
* return -1, and primitive reads will throw EOFExceptions. Note that this
* behavior does not hold for streams written with the old
* <code>ObjectStreamConstants.PROTOCOL_VERSION_1</code> protocol, in which the
* end of data written by writeExternal methods is not demarcated, and hence
* cannot be detected.
*
* <p>The readObjectNoData method is responsible for initializing the state of
* the object for its particular class in the event that the serialization
* stream does not list the given class as a superclass of the object being
* deserialized. This may occur in cases where the receiving party uses a
* different version of the deserialized instance's class than the sending
* party, and the receiver's version extends classes that are not extended by
* the sender's version. This may also occur if the serialization stream has
* been tampered; hence, readObjectNoData is useful for initializing
* deserialized objects properly despite a "hostile" or incomplete source
* stream.
*
* <p>Serialization does not read or assign values to the fields of any object
* that does not implement the java.io.Serializable interface. Subclasses of
* Objects that are not serializable can be serializable. In this case the
* non-serializable class must have a no-arg constructor to allow its fields to
* be initialized. In this case it is the responsibility of the subclass to
* save and restore the state of the non-serializable class. It is frequently
* the case that the fields of that class are accessible (public, package, or
* protected) or that there are get and set methods that can be used to restore
* the state.
*
* <p>Any exception that occurs while deserializing an object will be caught by
* the ObjectInputStream and abort the reading process.
*
* <p>Implementing the Externalizable interface allows the object to assume
* complete control over the contents and format of the object's serialized
* form. The methods of the Externalizable interface, writeExternal and
* readExternal, are called to save and restore the objects state. When
* implemented by a class they can write and read their own state using all of
* the methods of ObjectOutput and ObjectInput. It is the responsibility of
* the objects to handle any versioning that occurs.
*
* <p>Enum constants are deserialized differently than ordinary serializable or
* externalizable objects. The serialized form of an enum constant consists
* solely of its name; field values of the constant are not transmitted. To
* deserialize an enum constant, ObjectInputStream reads the constant name from
* the stream; the deserialized constant is then obtained by calling the static
* method <code>Enum.valueOf(Class, String)</code> with the enum constant's
* base type and the received constant name as arguments. Like other
* serializable or externalizable objects, enum constants can function as the
* targets of back references appearing subsequently in the serialization
* stream. The process by which enum constants are deserialized cannot be
* customized: any class-specific readObject, readObjectNoData, and readResolve
* methods defined by enum types are ignored during deserialization.
* Similarly, any serialPersistentFields or serialVersionUID field declarations
* are also ignored--all enum types have a fixed serialVersionUID of 0L.
*
* @author Mike Warres
* @author Roger Riggs
* @version 1.155, 04/05/28
* @see java.io.DataInput
* @see java.io.ObjectOutputStream
* @see java.io.Serializable
* @see <a href="../../../guide/serialization/spec/input.doc.html"> Object Serialization Specification, Section 3, Object Input Classes</a>
* @since JDK1.1
*/
public class ObjectInputStream
extends InputStream implements ObjectInput, ObjectStreamConstants
{
/** handle value representing null */
private static final int NULL_HANDLE = -1;
/** marker for unshared objects in internal handle table */
private static final Object unsharedMarker = new Object();
/** table mapping primitive type names to corresponding class objects */
private static final HashMap primClasses = new HashMap(8, 1.0F);
static {
primClasses.put("boolean", boolean.class);
primClasses.put("byte", byte.class);
primClasses.put("char", char.class);
primClasses.put("short", short.class);
primClasses.put("int", int.class);
primClasses.put("long", long.class);
primClasses.put("float", float.class);
primClasses.put("double", double.class);
primClasses.put("void", void.class);
}
/** cache of subclass security audit results */
private static final SoftCache subclassAudits = new SoftCache(5);
/** filter stream for handling block data conversion */
private final BlockDataInputStream bin;
/** validation callback list */
private final ValidationList vlist;
/** recursion depth */
private int depth;
/** whether stream is closed */
private boolean closed;
/** wire handle -> obj/exception map */
private final HandleTable handles;
/** scratch field for passing handle values up/down call stack */
private int passHandle = NULL_HANDLE;
/** flag set when at end of field value block with no TC_ENDBLOCKDATA */
private boolean defaultDataEnd = false;
/** buffer for reading primitive field values */
private byte[] primVals;
/** if true, invoke readObjectOverride() instead of readObject() */
private final boolean enableOverride;
/** if true, invoke resolveObject() */
private boolean enableResolve;
// values below valid only during upcalls to readObject()/readExternal()
/** object currently being deserialized */
private Object curObj;
/** descriptor for current class (null if in readExternal()) */
private ObjectStreamClass curDesc;
/** current GetField object */
private GetFieldImpl curGet;
/**
* Creates an ObjectInputStream that reads from the specified InputStream.
* A serialization stream header is read from the stream and verified.
* This constructor will block until the corresponding ObjectOutputStream
* has written and flushed the header.
*
* <p>If a security manager is installed, this constructor will check for
* the "enableSubclassImplementation" SerializablePermission when invoked
* directly or indirectly by the constructor of a subclass which overrides
* the ObjectInputStream.readFields or ObjectInputStream.readUnshared
* methods.
*
* @param in input stream to read from
* @throws StreamCorruptedException if the stream header is incorrect
* @throws IOException if an I/O error occurs while reading stream header
* @throws SecurityException if untrusted subclass illegally overrides
* security-sensitive methods
* @throws NullPointerException if <code>in</code> is <code>null</code>
* @see ObjectInputStream#ObjectInputStream()
* @see ObjectInputStream#readFields()
* @see ObjectOutputStream#ObjectOutputStream(OutputStream)
*/
public ObjectInputStream(InputStream in) throws IOException {
verifySubclass();
bin = new BlockDataInputStream(in);
handles = new HandleTable(10);
vlist = new ValidationList();
enableOverride = false;
readStreamHeader();
bin.setBlockDataMode(true);
}
/**
* Provide a way for subclasses that are completely reimplementing
* ObjectInputStream to not have to allocate private data just used by this
* implementation of ObjectInputStream.
*
* <p>If there is a security manager installed, this method first calls the
* security manager's <code>checkPermission</code> method with the
* <code>SerializablePermission("enableSubclassImplementation")</code>
* permission to ensure it's ok to enable subclassing.
*
* @throws SecurityException if a security manager exists and its
* <code>checkPermission</code> method denies enabling
* subclassing.
* @see SecurityManager#checkPermission
* @see java.io.SerializablePermission
*/
protected ObjectInputStream() throws IOException, SecurityException {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION);
}
bin = null;
handles = null;
vlist = null;
enableOverride = true;
}
/**
* Read an object from the ObjectInputStream. The class of the object, the
* signature of the class, and the values of the non-transient and
* non-static fields of the class and all of its supertypes are read.
* Default deserializing for a class can be overriden using the writeObject
* and readObject methods. Objects referenced by this object are read
* transitively so that a complete equivalent graph of objects is
* reconstructed by readObject.
*
* <p>The root object is completely restored when all of its fields and the
* objects it references are completely restored. At this point the object
* validation callbacks are executed in order based on their registered
* priorities. The callbacks are registered by objects (in the readObject
* special methods) as they are individually restored.
*
* <p>Exceptions are thrown for problems with the InputStream and for
* classes that should not be deserialized. All exceptions are fatal to
* the InputStream and leave it in an indeterminate state; it is up to the
* caller to ignore or recover the stream state.
*
* @throws ClassNotFoundException Class of a serialized object cannot be
* found.
* @throws InvalidClassException Something is wrong with a class used by
* serialization.
* @throws StreamCorruptedException Control information in the
* stream is inconsistent.
* @throws OptionalDataException Primitive data was found in the
* stream instead of objects.
* @throws IOException Any of the usual Input/Output related exceptions.
*/
public final Object readObject()
throws IOException, ClassNotFoundException
{
if (enableOverride) {
return readObjectOverride();
}
// if nested read, passHandle contains handle of enclosing object
int outerHandle = passHandle;
try {
Object obj = readObject0(false);
handles.markDependency(outerHandle, passHandle);
ClassNotFoundException ex = handles.lookupException(passHandle);
if (ex != null) {
throw ex;
}
if (depth == 0) {
vlist.doCallbacks();
}
return obj;
} finally {
passHandle = outerHandle;
if (closed && depth == 0) {
clear();
}
}
}
/**
* This method is called by trusted subclasses of ObjectOutputStream that
* constructed ObjectOutputStream using the protected no-arg constructor.
* The subclass is expected to provide an override method with the modifier
* "final".
*
* @return the Object read from the stream.
* @throws ClassNotFoundException Class definition of a serialized object
* cannot be found.
* @throws OptionalDataException Primitive data was found in the stream
* instead of objects.
* @throws IOException if I/O errors occurred while reading from the
* underlying stream
* @see #ObjectInputStream()
* @see #readObject()
* @since 1.2
*/
protected Object readObjectOverride()
throws IOException, ClassNotFoundException
{
return null;
}
/**
* Reads an "unshared" object from the ObjectInputStream. This method is
* identical to readObject, except that it prevents subsequent calls to
* readObject and readUnshared from returning additional references to the
* deserialized instance obtained via this call. Specifically:
* <ul>
* <li>If readUnshared is called to deserialize a back-reference (the
* stream representation of an object which has been written
* previously to the stream), an ObjectStreamException will be
* thrown.
*
* <li>If readUnshared returns successfully, then any subsequent attempts
* to deserialize back-references to the stream handle deserialized
* by readUnshared will cause an ObjectStreamException to be thrown.
* </ul>
* Deserializing an object via readUnshared invalidates the stream handle
* associated with the returned object. Note that this in itself does not
* always guarantee that the reference returned by readUnshared is unique;
* the deserialized object may define a readResolve method which returns an
* object visible to other parties, or readUnshared may return a Class
* object or enum constant obtainable elsewhere in the stream or through
* external means.
*
* <p>However, for objects which are not enum constants or instances of
* java.lang.Class and do not define readResolve methods, readUnshared
* guarantees that the returned object reference is unique and cannot be
* obtained a second time from the ObjectInputStream that created it, even
* if the underlying data stream has been manipulated. This guarantee
* applies only to the base-level object returned by readUnshared, and not
* to any transitively referenced sub-objects in the returned object graph.
*
* <p>ObjectInputStream subclasses which override this method can only be
* constructed in security contexts possessing the
* "enableSubclassImplementation" SerializablePermission; any attempt to
* instantiate such a subclass without this permission will cause a
* SecurityException to be thrown.
*
* @return reference to deserialized object
* @throws ClassNotFoundException if class of an object to deserialize
* cannot be found
* @throws StreamCorruptedException if control information in the stream
* is inconsistent
* @throws ObjectStreamException if object to deserialize has already
* appeared in stream
* @throws OptionalDataException if primitive data is next in stream
* @throws IOException if an I/O error occurs during deserialization
*/
public Object readUnshared() throws IOException, ClassNotFoundException {
// if nested read, passHandle contains handle of enclosing object
int outerHandle = passHandle;
try {
Object obj = readObject0(true);
handles.markDependency(outerHandle, passHandle);
ClassNotFoundException ex = handles.lookupException(passHandle);
if (ex != null) {
throw ex;
}
if (depth == 0) {
vlist.doCallbacks();
}
return obj;
} finally {
passHandle = outerHandle;
if (closed && depth == 0) {
clear();
}
}
}
/**
* Read the non-static and non-transient fields of the current class from
* this stream. This may only be called from the readObject method of the
* class being deserialized. It will throw the NotActiveException if it is
* called otherwise.
*
* @throws ClassNotFoundException if the class of a serialized object
* could not be found.
* @throws IOException if an I/O error occurs.
* @throws NotActiveException if the stream is not currently reading
* objects.
*/
public void defaultReadObject()
throws IOException, ClassNotFoundException
{
if (curObj == null || curDesc == null) {
throw new NotActiveException("not in call to readObject");
}
bin.setBlockDataMode(false);
defaultReadFields(curObj, curDesc);
bin.setBlockDataMode(true);
if (!curDesc.hasWriteObjectData()) {
/*
* Fix for 4360508: since stream does not contain terminating
* TC_ENDBLOCKDATA tag, set flag so that reading code elsewhere
* knows to simulate end-of-custom-data behavior.
*/
defaultDataEnd = true;
}
ClassNotFoundException ex = handles.lookupException(passHandle);
if (ex != null) {
throw ex;
}
}
/**
* Reads the persistent fields from the stream and makes them available by
* name.
*
* @return the <code>GetField</code> object representing the persistent
* fields of the object being deserialized
* @throws ClassNotFoundException if the class of a serialized object
* could not be found.
* @throws IOException if an I/O error occurs.
* @throws NotActiveException if the stream is not currently reading
* objects.
* @since 1.2
*/
public ObjectInputStream.GetField readFields()
throws IOException, ClassNotFoundException
{
if (curGet == null) {
if (curObj == null || curDesc == null) {
throw new NotActiveException("not in call to readObject");
}
curGet = new GetFieldImpl(curDesc);
}
bin.setBlockDataMode(false);
curGet.readFields();
bin.setBlockDataMode(true);
if (!curDesc.hasWriteObjectData()) {
/*
* Fix for 4360508: since stream does not contain terminating
* TC_ENDBLOCKDATA tag, set flag so that reading code elsewhere
* knows to simulate end-of-custom-data behavior.
*/
defaultDataEnd = true;
}
return curGet;
}
/**
* Register an object to be validated before the graph is returned. While
* similar to resolveObject these validations are called after the entire
* graph has been reconstituted. Typically, a readObject method will
* register the object with the stream so that when all of the objects are
* restored a final set of validations can be performed.
*
* @param obj the object to receive the validation callback.
* @param prio controls the order of callbacks;zero is a good default.
* Use higher numbers to be called back earlier, lower numbers for
* later callbacks. Within a priority, callbacks are processed in
* no particular order.
* @throws NotActiveException The stream is not currently reading objects
* so it is invalid to register a callback.
* @throws InvalidObjectException The validation object is null.
*/
public void registerValidation(ObjectInputValidation obj, int prio)
throws NotActiveException, InvalidObjectException
{
if (depth == 0) {
throw new NotActiveException("stream inactive");
}
vlist.register(obj, prio);
}
/**
* Load the local class equivalent of the specified stream class
* description. Subclasses may implement this method to allow classes to
* be fetched from an alternate source.
*
* <p>The corresponding method in <code>ObjectOutputStream</code> is
* <code>annotateClass</code>. This method will be invoked only once for
* each unique class in the stream. This method can be implemented by
* subclasses to use an alternate loading mechanism but must return a
* <code>Class</code> object. Once returned, the serialVersionUID of the
* class is compared to the serialVersionUID of the serialized class. If
* there is a mismatch, the deserialization fails and an exception is
* raised.
*
* <p>By default the class name is resolved relative to the class that
* called <code>readObject</code>.
*
* @param desc an instance of class <code>ObjectStreamClass</code>
* @return a <code>Class</code> object corresponding to <code>desc</code>
* @throws IOException any of the usual input/output exceptions
* @throws ClassNotFoundException if class of a serialized object cannot
* be found
*/
protected Class<?> resolveClass(ObjectStreamClass desc)
throws IOException, ClassNotFoundException
{
String name = desc.getName();
try {
return Class.forName(name, false, latestUserDefinedLoader());
} catch (ClassNotFoundException ex) {
Class cl = (Class) primClasses.get(name);
if (cl != null) {
return cl;
} else {
throw ex;
}
}
}
/**
* Returns a proxy class that implements the interfaces named in a proxy
* class descriptor; subclasses may implement this method to read custom
* data from the stream along with the descriptors for dynamic proxy
* classes, allowing them to use an alternate loading mechanism for the
* interfaces and the proxy class.
*
* <p>This method is called exactly once for each unique proxy class
* descriptor in the stream.
*
* <p>The corresponding method in <code>ObjectOutputStream</code> is
* <code>annotateProxyClass</code>. For a given subclass of
* <code>ObjectInputStream</code> that overrides this method, the
* <code>annotateProxyClass</code> method in the corresponding subclass of
* <code>ObjectOutputStream</code> must write any data or objects read by
* this method.
*
* <p>The default implementation of this method in
* <code>ObjectInputStream</code> returns the result of calling
* <code>Proxy.getProxyClass</code> with the list of <code>Class</code>
* objects for the interfaces that are named in the <code>interfaces</code>
* parameter. The <code>Class</code> object for each interface name
* <code>i</code> is the value returned by calling
* <pre>
* Class.forName(i, false, loader)
* </pre>
* where <code>loader</code> is that of the first non-<code>null</code>
* class loader up the execution stack, or <code>null</code> if no
* non-<code>null</code> class loaders are on the stack (the same class
* loader choice used by the <code>resolveClass</code> method). Unless any
* of the resolved interfaces are non-public, this same value of
* <code>loader</code> is also the class loader passed to
* <code>Proxy.getProxyClass</code>; if non-public interfaces are present,
* their class loader is passed instead (if more than one non-public
* interface class loader is encountered, an
* <code>IllegalAccessError</code> is thrown).
* If <code>Proxy.getProxyClass</code> throws an
* <code>IllegalArgumentException</code>, <code>resolveProxyClass</code>
* will throw a <code>ClassNotFoundException</code> containing the
* <code>IllegalArgumentException</code>.
*
* @param interfaces the list of interface names that were
* deserialized in the proxy class descriptor
* @return a proxy class for the specified interfaces
* @throws IOException any exception thrown by the underlying
* <code>InputStream</code>
* @throws ClassNotFoundException if the proxy class or any of the
* named interfaces could not be found
* @see ObjectOutputStream#annotateProxyClass(Class)
* @since 1.3
*/
protected Class<?> resolveProxyClass(String[] interfaces)
throws IOException, ClassNotFoundException
{
ClassLoader latestLoader = latestUserDefinedLoader();
ClassLoader nonPublicLoader = null;
boolean hasNonPublicInterface = false;
// define proxy in class loader of non-public interface(s), if any
Class[] classObjs = new Class[interfaces.length];
for (int i = 0; i < interfaces.length; i++) {
Class cl = Class.forName(interfaces[i], false, latestLoader);
if ((cl.getModifiers() & Modifier.PUBLIC) == 0) {
if (hasNonPublicInterface) {
if (nonPublicLoader != cl.getClassLoader()) {
throw new IllegalAccessError(
"conflicting non-public interface class loaders");
}
} else {
nonPublicLoader = cl.getClassLoader();
hasNonPublicInterface = true;
}
}
classObjs[i] = cl;
}
try {
return Proxy.getProxyClass(
hasNonPublicInterface ? nonPublicLoader : latestLoader,
classObjs);
} catch (IllegalArgumentException e) {
throw new ClassNotFoundException(null, e);
}
}
/**
* This method will allow trusted subclasses of ObjectInputStream to
* substitute one object for another during deserialization. Replacing
* objects is disabled until enableResolveObject is called. The
* enableResolveObject method checks that the stream requesting to resolve
* object can be trusted. Every reference to serializable objects is passed
* to resolveObject. To insure that the private state of objects is not
* unintentionally exposed only trusted streams may use resolveObject.
*
* <p>This method is called after an object has been read but before it is
* returned from readObject. The default resolveObject method just returns
* the same object.
*
* <p>When a subclass is replacing objects it must insure that the
* substituted object is compatible with every field where the reference
* will be stored. Objects whose type is not a subclass of the type of the
* field or array element abort the serialization by raising an exception
* and the object is not be stored.
*
* <p>This method is called only once when each object is first
* encountered. All subsequent references to the object will be redirected
* to the new object.
*
* @param obj object to be substituted
* @return the substituted object
* @throws IOException Any of the usual Input/Output exceptions.
*/
protected Object resolveObject(Object obj) throws IOException {
return obj;
}
/**
* Enable the stream to allow objects read from the stream to be replaced.
* When enabled, the resolveObject method is called for every object being
* deserialized.
*
* <p>If <i>enable</i> is true, and there is a security manager installed,
* this method first calls the security manager's
* <code>checkPermission</code> method with the
* <code>SerializablePermission("enableSubstitution")</code> permission to
* ensure it's ok to enable the stream to allow objects read from the
* stream to be replaced.
*
* @param enable true for enabling use of <code>resolveObject</code> for
* every object being deserialized
* @return the previous setting before this method was invoked
* @throws SecurityException if a security manager exists and its
* <code>checkPermission</code> method denies enabling the stream
* to allow objects read from the stream to be replaced.
* @see SecurityManager#checkPermission
* @see java.io.SerializablePermission
*/
protected boolean enableResolveObject(boolean enable)
throws SecurityException
{
if (enable == enableResolve) {
return enable;
}
if (enable) {
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPermission(SUBSTITUTION_PERMISSION);
}
}
enableResolve = enable;
return !enableResolve;
}
/**
* The readStreamHeader method is provided to allow subclasses to read and
* verify their own stream headers. It reads and verifies the magic number
* and version number.
*
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws StreamCorruptedException if control information in the stream
* is inconsistent
*/
protected void readStreamHeader()
throws IOException, StreamCorruptedException
{
if (bin.readShort() != STREAM_MAGIC ||
bin.readShort() != STREAM_VERSION)
{
throw new StreamCorruptedException("invalid stream header");
}
}
/**
* Read a class descriptor from the serialization stream. This method is
* called when the ObjectInputStream expects a class descriptor as the next
* item in the serialization stream. Subclasses of ObjectInputStream may
* override this method to read in class descriptors that have been written
* in non-standard formats (by subclasses of ObjectOutputStream which have
* overridden the <code>writeClassDescriptor</code> method). By default,
* this method reads class descriptors according to the format defined in
* the Object Serialization specification.
*
* @return the class descriptor read
* @throws IOException If an I/O error has occurred.
* @throws ClassNotFoundException If the Class of a serialized object used
* in the class descriptor representation cannot be found
* @see java.io.ObjectOutputStream#writeClassDescriptor(java.io.ObjectStreamClass)
* @since 1.3
*/
protected ObjectStreamClass readClassDescriptor()
throws IOException, ClassNotFoundException
{
ObjectStreamClass desc = new ObjectStreamClass();
desc.readNonProxy(this);
return desc;
}
/**
* Reads a byte of data. This method will block if no input is available.
*
* @return the byte read, or -1 if the end of the stream is reached.
* @throws IOException If an I/O error has occurred.
*/
public int read() throws IOException {
return bin.read();
}
/**
* Reads into an array of bytes. This method will block until some input
* is available. Consider using java.io.DataInputStream.readFully to read
* exactly 'length' bytes.
*
* @param buf the buffer into which the data is read
* @param off the start offset of the data
* @param len the maximum number of bytes read
* @return the actual number of bytes read, -1 is returned when the end of
* the stream is reached.
* @throws IOException If an I/O error has occurred.
* @see java.io.DataInputStream#readFully(byte[],int,int)
*/
public int read(byte[] buf, int off, int len) throws IOException {
if (buf == null) {
throw new NullPointerException();
}
int endoff = off + len;
if (off < 0 || len < 0 || endoff > buf.length || endoff < 0) {
throw new IndexOutOfBoundsException();
}
return bin.read(buf, off, len, false);
}
/**
* Returns the number of bytes that can be read without blocking.
*
* @return the number of available bytes.
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
*/
public int available() throws IOException {
return bin.available();
}
/**
* Closes the input stream. Must be called to release any resources
* associated with the stream.
*
* @throws IOException If an I/O error has occurred.
*/
public void close() throws IOException {
/*
* Even if stream already closed, propagate redundant close to
* underlying stream to stay consistent with previous implementations.
*/
closed = true;
if (depth == 0) {
clear();
}
bin.close();
}
/**
* Reads in a boolean.
*
* @return the boolean read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public boolean readBoolean() throws IOException {
return bin.readBoolean();
}
/**
* Reads an 8 bit byte.
*
* @return the 8 bit byte read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public byte readByte() throws IOException {
return bin.readByte();
}
/**
* Reads an unsigned 8 bit byte.
*
* @return the 8 bit byte read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public int readUnsignedByte() throws IOException {
return bin.readUnsignedByte();
}
/**
* Reads a 16 bit char.
*
* @return the 16 bit char read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public char readChar() throws IOException {
return bin.readChar();
}
/**
* Reads a 16 bit short.
*
* @return the 16 bit short read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public short readShort() throws IOException {
return bin.readShort();
}
/**
* Reads an unsigned 16 bit short.
*
* @return the 16 bit short read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public int readUnsignedShort() throws IOException {
return bin.readUnsignedShort();
}
/**
* Reads a 32 bit int.
*
* @return the 32 bit integer read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public int readInt() throws IOException {
return bin.readInt();
}
/**
* Reads a 64 bit long.
*
* @return the read 64 bit long.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public long readLong() throws IOException {
return bin.readLong();
}
/**
* Reads a 32 bit float.
*
* @return the 32 bit float read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public float readFloat() throws IOException {
return bin.readFloat();
}
/**
* Reads a 64 bit double.
*
* @return the 64 bit double read.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public double readDouble() throws IOException {
return bin.readDouble();
}
/**
* Reads bytes, blocking until all bytes are read.
*
* @param buf the buffer into which the data is read
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public void readFully(byte[] buf) throws IOException {
bin.readFully(buf, 0, buf.length, false);
}
/**
* Reads bytes, blocking until all bytes are read.
*
* @param buf the buffer into which the data is read
* @param off the start offset of the data
* @param len the maximum number of bytes to read
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public void readFully(byte[] buf, int off, int len) throws IOException {
int endoff = off + len;
if (off < 0 || len < 0 || endoff > buf.length || endoff < 0) {
throw new IndexOutOfBoundsException();
}
bin.readFully(buf, off, len, false);
}
/**
* Skips bytes, block until all bytes are skipped.
*
* @param len the number of bytes to be skipped
* @return the actual number of bytes skipped.
* @throws EOFException If end of file is reached.
* @throws IOException If other I/O error has occurred.
*/
public int skipBytes(int len) throws IOException {
return bin.skipBytes(len);
}
/**
* Reads in a line that has been terminated by a \n, \r, \r\n or EOF.
*
* @return a String copy of the line.
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @deprecated This method does not properly convert bytes to characters.
* see DataInputStream for the details and alternatives.
*/
@Deprecated
public String readLine() throws IOException {
return bin.readLine();
}
/**
* Reads a String in
* <a href="DataInput.html#modified-utf-8">modified UTF-8</a>
* format.
*
* @return the String.
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws UTFDataFormatException if read bytes do not represent a valid
* modified UTF-8 encoding of a string
*/
public String readUTF() throws IOException {
return bin.readUTF();
}
/**
* Provide access to the persistent fields read from the input stream.
*/
public static abstract class GetField {
/**
* Get the ObjectStreamClass that describes the fields in the stream.
*
* @return the descriptor class that describes the serializable fields
*/
public abstract ObjectStreamClass getObjectStreamClass();
/**
* Return true if the named field is defaulted and has no value in this
* stream.
*
* @param name the name of the field
* @return true, if and only if the named field is defaulted
* @throws IOException if there are I/O errors while reading from
* the underlying <code>InputStream</code>
* @throws IllegalArgumentException if <code>name</code> does not
* correspond to a serializable field
*/
public abstract boolean defaulted(String name) throws IOException;
/**
* Get the value of the named boolean field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>boolean</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract boolean get(String name, boolean val)
throws IOException;
/**
* Get the value of the named byte field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>byte</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract byte get(String name, byte val) throws IOException;
/**
* Get the value of the named char field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>char</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract char get(String name, char val) throws IOException;
/**
* Get the value of the named short field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>short</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract short get(String name, short val) throws IOException;
/**
* Get the value of the named int field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>int</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract int get(String name, int val) throws IOException;
/**
* Get the value of the named long field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>long</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract long get(String name, long val) throws IOException;
/**
* Get the value of the named float field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>float</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract float get(String name, float val) throws IOException;
/**
* Get the value of the named double field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>double</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract double get(String name, double val) throws IOException;
/**
* Get the value of the named Object field from the persistent field.
*
* @param name the name of the field
* @param val the default value to use if <code>name</code> does not
* have a value
* @return the value of the named <code>Object</code> field
* @throws IOException if there are I/O errors while reading from the
* underlying <code>InputStream</code>
* @throws IllegalArgumentException if type of <code>name</code> is
* not serializable or if the field type is incorrect
*/
public abstract Object get(String name, Object val) throws IOException;
}
/**
* Verifies that this (possibly subclass) instance can be constructed
* without violating security constraints: the subclass must not override
* security-sensitive non-final methods, or else the
* "enableSubclassImplementation" SerializablePermission is checked.
*/
private void verifySubclass() {
Class cl = getClass();
synchronized (subclassAudits) {
Boolean result = (Boolean) subclassAudits.get(cl);
if (result == null) {
/*
* Note: only new Boolean instances (i.e., not Boolean.TRUE or
* Boolean.FALSE) must be used as cache values, otherwise cache
* entry will pin associated class.
*/
result = new Boolean(auditSubclass(cl));
subclassAudits.put(cl, result);
}
if (result.booleanValue()) {
return;
}
}
SecurityManager sm = System.getSecurityManager();
if (sm != null) {
sm.checkPermission(SUBCLASS_IMPLEMENTATION_PERMISSION);
}
}
/**
* Performs reflective checks on given subclass to verify that it doesn't
* override security-sensitive non-final methods. Returns true if subclass
* is "safe", false otherwise.
*/
private static boolean auditSubclass(final Class subcl) {
Boolean result = (Boolean) AccessController.doPrivileged(
new PrivilegedAction() {
public Object run() {
for (Class cl = subcl;
cl != ObjectInputStream.class;
cl = cl.getSuperclass())
{
try {
cl.getDeclaredMethod("readUnshared", new Class[0]);
return Boolean.FALSE;
} catch (NoSuchMethodException ex) {
}
try {
cl.getDeclaredMethod("readFields", new Class[0]);
return Boolean.FALSE;
} catch (NoSuchMethodException ex) {
}
}
return Boolean.TRUE;
}
}
);
return result.booleanValue();
}
/**
* Clears internal data structures.
*/
private void clear() {
handles.clear();
vlist.clear();
}
/**
* Underlying readObject implementation.
*/
private Object readObject0(boolean unshared) throws IOException {
boolean oldMode = bin.getBlockDataMode();
if (oldMode) {
int remain = bin.currentBlockRemaining();
if (remain > 0) {
throw new OptionalDataException(remain);
} else if (defaultDataEnd) {
/*
* Fix for 4360508: stream is currently at the end of a field
* value block written via default serialization; since there
* is no terminating TC_ENDBLOCKDATA tag, simulate
* end-of-custom-data behavior explicitly.
*/
throw new OptionalDataException(true);
}
bin.setBlockDataMode(false);
}
byte tc;
while ((tc = bin.peekByte()) == TC_RESET) {
bin.readByte();
handleReset();
}
depth++;
try {
switch (tc) {
case TC_NULL:
return readNull();
case TC_REFERENCE:
return readHandle(unshared);
case TC_CLASS:
return readClass(unshared);
case TC_CLASSDESC:
case TC_PROXYCLASSDESC:
return readClassDesc(unshared);
case TC_STRING:
case TC_LONGSTRING:
return checkResolve(readString(unshared));
case TC_ARRAY:
return checkResolve(readArray(unshared));
case TC_ENUM:
return checkResolve(readEnum(unshared));
case TC_OBJECT:
return checkResolve(readOrdinaryObject(unshared));
case TC_EXCEPTION:
IOException ex = readFatalException();
throw new WriteAbortedException("writing aborted", ex);
case TC_BLOCKDATA:
case TC_BLOCKDATALONG:
if (oldMode) {
bin.setBlockDataMode(true);
bin.peek(); // force header read
throw new OptionalDataException(
bin.currentBlockRemaining());
} else {
throw new StreamCorruptedException(
"unexpected block data");
}
case TC_ENDBLOCKDATA:
if (oldMode) {
throw new OptionalDataException(true);
} else {
throw new StreamCorruptedException(
"unexpected end of block data");
}
default:
throw new StreamCorruptedException();
}
} finally {
depth--;
bin.setBlockDataMode(oldMode);
}
}
/**
* If resolveObject has been enabled and given object does not have an
* exception associated with it, calls resolveObject to determine
* replacement for object, and updates handle table accordingly. Returns
* replacement object, or echoes provided object if no replacement
* occurred. Expects that passHandle is set to given object's handle prior
* to calling this method.
*/
private Object checkResolve(Object obj) throws IOException {
if (!enableResolve || handles.lookupException(passHandle) != null) {
return obj;
}
Object rep = resolveObject(obj);
if (rep != obj) {
handles.setObject(passHandle, rep);
}
return rep;
}
/**
* Reads string without allowing it to be replaced in stream. Called from
* within ObjectStreamClass.read().
*/
String readTypeString() throws IOException {
int oldHandle = passHandle;
try {
switch (bin.peekByte()) {
case TC_NULL:
return (String) readNull();
case TC_REFERENCE:
return (String) readHandle(false);
case TC_STRING:
case TC_LONGSTRING:
return readString(false);
default:
throw new StreamCorruptedException();
}
} finally {
passHandle = oldHandle;
}
}
/**
* Reads in null code, sets passHandle to NULL_HANDLE and returns null.
*/
private Object readNull() throws IOException {
if (bin.readByte() != TC_NULL) {
throw new StreamCorruptedException();
}
passHandle = NULL_HANDLE;
return null;
}
/**
* Reads in object handle, sets passHandle to the read handle, and returns
* object associated with the handle.
*/
private Object readHandle(boolean unshared) throws IOException {
if (bin.readByte() != TC_REFERENCE) {
throw new StreamCorruptedException();
}
passHandle = bin.readInt() - baseWireHandle;
if (passHandle < 0 || passHandle >= handles.size()) {
throw new StreamCorruptedException("illegal handle value");
}
if (unshared) {
// REMIND: what type of exception to throw here?
throw new InvalidObjectException(
"cannot read back reference as unshared");
}
Object obj = handles.lookupObject(passHandle);
if (obj == unsharedMarker) {
// REMIND: what type of exception to throw here?
throw new InvalidObjectException(
"cannot read back reference to unshared object");
}
return obj;
}
/**
* Reads in and returns class object. Sets passHandle to class object's
* assigned handle. Returns null if class is unresolvable (in which case a
* ClassNotFoundException will be associated with the class' handle in the
* handle table).
*/
private Class readClass(boolean unshared) throws IOException {
if (bin.readByte() != TC_CLASS) {
throw new StreamCorruptedException();
}
ObjectStreamClass desc = readClassDesc(false);
Class cl = desc.forClass();
passHandle = handles.assign(unshared ? unsharedMarker : cl);
ClassNotFoundException resolveEx = desc.getResolveException();
if (resolveEx != null) {
handles.markException(passHandle, resolveEx);
}
handles.finish(passHandle);
return cl;
}
/**
* Reads in and returns (possibly null) class descriptor. Sets passHandle
* to class descriptor's assigned handle. If class descriptor cannot be
* resolved to a class in the local VM, a ClassNotFoundException is
* associated with the class descriptor's handle.
*/
private ObjectStreamClass readClassDesc(boolean unshared)
throws IOException
{
switch (bin.peekByte()) {
case TC_NULL:
return (ObjectStreamClass) readNull();
case TC_REFERENCE:
return (ObjectStreamClass) readHandle(unshared);
case TC_PROXYCLASSDESC:
return readProxyDesc(unshared);
case TC_CLASSDESC:
return readNonProxyDesc(unshared);
default:
throw new StreamCorruptedException();
}
}
/**
* Reads in and returns class descriptor for a dynamic proxy class. Sets
* passHandle to proxy class descriptor's assigned handle. If proxy class
* descriptor cannot be resolved to a class in the local VM, a
* ClassNotFoundException is associated with the descriptor's handle.
*/
private ObjectStreamClass readProxyDesc(boolean unshared)
throws IOException
{
if (bin.readByte() != TC_PROXYCLASSDESC) {
throw new StreamCorruptedException();
}
ObjectStreamClass desc = new ObjectStreamClass();
int descHandle = handles.assign(unshared ? unsharedMarker : desc);
passHandle = NULL_HANDLE;
int numIfaces = bin.readInt();
String[] ifaces = new String[numIfaces];
for (int i = 0; i < numIfaces; i++) {
ifaces[i] = bin.readUTF();
}
Class cl = null;
ClassNotFoundException resolveEx = null;
bin.setBlockDataMode(true);
try {
if ((cl = resolveProxyClass(ifaces)) == null) {
throw new ClassNotFoundException("null class");
}
} catch (ClassNotFoundException ex) {
resolveEx = ex;
}
skipCustomData();
desc.initProxy(cl, resolveEx, readClassDesc(false));
handles.finish(descHandle);
passHandle = descHandle;
return desc;
}
/**
* Reads in and returns class descriptor for a class that is not a dynamic
* proxy class. Sets passHandle to class descriptor's assigned handle. If
* class descriptor cannot be resolved to a class in the local VM, a
* ClassNotFoundException is associated with the descriptor's handle.
*/
private ObjectStreamClass readNonProxyDesc(boolean unshared)
throws IOException
{
if (bin.readByte() != TC_CLASSDESC) {
throw new StreamCorruptedException();
}
ObjectStreamClass desc = new ObjectStreamClass();
int descHandle = handles.assign(unshared ? unsharedMarker : desc);
passHandle = NULL_HANDLE;
ObjectStreamClass readDesc = null;
try {
readDesc = readClassDescriptor();
} catch (ClassNotFoundException ex) {
throw (IOException) new InvalidClassException(
"failed to read class descriptor").initCause(ex);
}
Class cl = null;
ClassNotFoundException resolveEx = null;
bin.setBlockDataMode(true);
try {
if ((cl = resolveClass(readDesc)) == null) {
throw new ClassNotFoundException("null class");
}
} catch (ClassNotFoundException ex) {
resolveEx = ex;
}
skipCustomData();
desc.initNonProxy(readDesc, cl, resolveEx, readClassDesc(false));
handles.finish(descHandle);
passHandle = descHandle;
return desc;
}
/**
* Reads in and returns new string. Sets passHandle to new string's
* assigned handle.
*/
private String readString(boolean unshared) throws IOException {
String str;
switch (bin.readByte()) {
case TC_STRING:
str = bin.readUTF();
break;
case TC_LONGSTRING:
str = bin.readLongUTF();
break;
default:
throw new StreamCorruptedException();
}
passHandle = handles.assign(unshared ? unsharedMarker : str);
handles.finish(passHandle);
return str;
}
/**
* Reads in and returns array object, or null if array class is
* unresolvable. Sets passHandle to array's assigned handle.
*/
private Object readArray(boolean unshared) throws IOException {
if (bin.readByte() != TC_ARRAY) {
throw new StreamCorruptedException();
}
ObjectStreamClass desc = readClassDesc(false);
int len = bin.readInt();
Object array = null;
Class cl, ccl = null;
if ((cl = desc.forClass()) != null) {
ccl = cl.getComponentType();
array = Array.newInstance(ccl, len);
}
int arrayHandle = handles.assign(unshared ? unsharedMarker : array);
ClassNotFoundException resolveEx = desc.getResolveException();
if (resolveEx != null) {
handles.markException(arrayHandle, resolveEx);
}
if (ccl == null) {
for (int i = 0; i < len; i++) {
readObject0(false);
}
} else if (ccl.isPrimitive()) {
if (ccl == Integer.TYPE) {
bin.readInts((int[]) array, 0, len);
} else if (ccl == Byte.TYPE) {
bin.readFully((byte[]) array, 0, len, true);
} else if (ccl == Long.TYPE) {
bin.readLongs((long[]) array, 0, len);
} else if (ccl == Float.TYPE) {
bin.readFloats((float[]) array, 0, len);
} else if (ccl == Double.TYPE) {
bin.readDoubles((double[]) array, 0, len);
} else if (ccl == Short.TYPE) {
bin.readShorts((short[]) array, 0, len);
} else if (ccl == Character.TYPE) {
bin.readChars((char[]) array, 0, len);
} else if (ccl == Boolean.TYPE) {
bin.readBooleans((boolean[]) array, 0, len);
} else {
throw new InternalError();
}
} else {
Object[] oa = (Object[]) array;
for (int i = 0; i < len; i++) {
oa[i] = readObject0(false);
handles.markDependency(arrayHandle, passHandle);
}
}
handles.finish(arrayHandle);
passHandle = arrayHandle;
return array;
}
/**
* Reads in and returns enum constant, or null if enum type is
* unresolvable. Sets passHandle to enum constant's assigned handle.
*/
private Enum readEnum(boolean unshared) throws IOException {
if (bin.readByte() != TC_ENUM) {
throw new StreamCorruptedException();
}
ObjectStreamClass desc = readClassDesc(false);
if (!desc.isEnum()) {
throw new InvalidClassException("non-enum class: " + desc);
}
int enumHandle = handles.assign(unshared ? unsharedMarker : null);
ClassNotFoundException resolveEx = desc.getResolveException();
if (resolveEx != null) {
handles.markException(enumHandle, resolveEx);
}
String name = readString(false);
Enum en = null;
Class cl = desc.forClass();
if (cl != null) {
try {
en = Enum.valueOf(cl, name);
} catch (IllegalArgumentException ex) {
throw (IOException) new InvalidObjectException(
"enum constant " + name + " does not exist in " +
cl).initCause(ex);
}
if (!unshared) {
handles.setObject(enumHandle, en);
}
}
handles.finish(enumHandle);
passHandle = enumHandle;
return en;
}
/**
* Reads and returns "ordinary" (i.e., not a String, Class,
* ObjectStreamClass, array, or enum constant) object, or null if object's
* class is unresolvable (in which case a ClassNotFoundException will be
* associated with object's handle). Sets passHandle to object's assigned
* handle.
*/
private Object readOrdinaryObject(boolean unshared)
throws IOException
{
if (bin.readByte() != TC_OBJECT) {
throw new StreamCorruptedException();
}
ObjectStreamClass desc = readClassDesc(false);
desc.checkDeserialize();
Object obj;
try {
obj = desc.isInstantiable() ? desc.newInstance() : null;
} catch (Exception ex) {
throw new InvalidClassException(
desc.forClass().getName(), "unable to create instance");
}
passHandle = handles.assign(unshared ? unsharedMarker : obj);
ClassNotFoundException resolveEx = desc.getResolveException();
if (resolveEx != null) {
handles.markException(passHandle, resolveEx);
}
if (desc.isExternalizable()) {
readExternalData((Externalizable) obj, desc);
} else {
readSerialData(obj, desc);
}
handles.finish(passHandle);
if (obj != null &&
handles.lookupException(passHandle) == null &&
desc.hasReadResolveMethod())
{
Object rep = desc.invokeReadResolve(obj);
if (rep != obj) {
handles.setObject(passHandle, obj = rep);
}
}
return obj;
}
/**
* If obj is non-null, reads externalizable data by invoking readExternal()
* method of obj; otherwise, attempts to skip over externalizable data.
* Expects that passHandle is set to obj's handle before this method is
* called.
*/
private void readExternalData(Externalizable obj, ObjectStreamClass desc)
throws IOException
{
Object oldObj = curObj;
ObjectStreamClass oldDesc = curDesc;
GetFieldImpl oldGet = curGet;
curObj = obj;
curDesc = null;
curGet = null;
boolean blocked = desc.hasBlockExternalData();
if (blocked) {
bin.setBlockDataMode(true);
}
if (obj != null) {
try {
obj.readExternal(this);
} catch (ClassNotFoundException ex) {
/*
* In most cases, the handle table has already propagated a
* CNFException to passHandle at this point; this mark call is
* included to address cases where the readExternal method has
* cons'ed and thrown a new CNFException of its own.
*/
handles.markException(passHandle, ex);
}
}
if (blocked) {
skipCustomData();
}
/*
* At this point, if the externalizable data was not written in
* block-data form and either the externalizable class doesn't exist
* locally (i.e., obj == null) or readExternal() just threw a
* CNFException, then the stream is probably in an inconsistent state,
* since some (or all) of the externalizable data may not have been
* consumed. Since there's no "correct" action to take in this case,
* we mimic the behavior of past serialization implementations and
* blindly hope that the stream is in sync; if it isn't and additional
* externalizable data remains in the stream, a subsequent read will
* most likely throw a StreamCorruptedException.
*/
curObj = oldObj;
curDesc = oldDesc;
curGet = oldGet;
}
/**
* Reads (or attempts to skip, if obj is null or is tagged with a
* ClassNotFoundException) instance data for each serializable class of
* object in stream, from superclass to subclass. Expects that passHandle
* is set to obj's handle before this method is called.
*/
private void readSerialData(Object obj, ObjectStreamClass desc)
throws IOException
{
ObjectStreamClass.ClassDataSlot[] slots = desc.getClassDataLayout();
for (int i = 0; i < slots.length; i++) {
ObjectStreamClass slotDesc = slots[i].desc;
if (slots[i].hasData) {
if (obj != null &&
slotDesc.hasReadObjectMethod() &&
handles.lookupException(passHandle) == null)
{
Object oldObj = curObj;
ObjectStreamClass oldDesc = curDesc;
GetFieldImpl oldGet = curGet;
curObj = obj;
curDesc = slotDesc;
curGet = null;
bin.setBlockDataMode(true);
try {
slotDesc.invokeReadObject(obj, this);
} catch (ClassNotFoundException ex) {
/*
* In most cases, the handle table has already
* propagated a CNFException to passHandle at this
* point; this mark call is included to address cases
* where the custom readObject method has cons'ed and
* thrown a new CNFException of its own.
*/
handles.markException(passHandle, ex);
}
curObj = oldObj;
curDesc = oldDesc;
curGet = oldGet;
/*
* defaultDataEnd may have been set indirectly by custom
* readObject() method when calling defaultReadObject() or
* readFields(); clear it to restore normal read behavior.
*/
defaultDataEnd = false;
} else {
defaultReadFields(obj, slotDesc);
}
if (slotDesc.hasWriteObjectData()) {
skipCustomData();
} else {
bin.setBlockDataMode(false);
}
} else {
if (obj != null &&
slotDesc.hasReadObjectNoDataMethod() &&
handles.lookupException(passHandle) == null)
{
slotDesc.invokeReadObjectNoData(obj);
}
}
}
}
/**
* Skips over all block data and objects until TC_ENDBLOCKDATA is
* encountered.
*/
private void skipCustomData() throws IOException {
int oldHandle = passHandle;
for (;;) {
if (bin.getBlockDataMode()) {
bin.skipBlockData();
bin.setBlockDataMode(false);
}
switch (bin.peekByte()) {
case TC_BLOCKDATA:
case TC_BLOCKDATALONG:
bin.setBlockDataMode(true);
break;
case TC_ENDBLOCKDATA:
bin.readByte();
passHandle = oldHandle;
return;
default:
readObject0(false);
break;
}
}
}
/**
* Reads in values of serializable fields declared by given class
* descriptor. If obj is non-null, sets field values in obj. Expects that
* passHandle is set to obj's handle before this method is called.
*/
private void defaultReadFields(Object obj, ObjectStreamClass desc)
throws IOException
{
// REMIND: is isInstance check necessary?
Class cl = desc.forClass();
if (cl != null && obj != null && !cl.isInstance(obj)) {
throw new ClassCastException();
}
int primDataSize = desc.getPrimDataSize();
if (primVals == null || primVals.length < primDataSize) {
primVals = new byte[primDataSize];
}
bin.readFully(primVals, 0, primDataSize, false);
if (obj != null) {
desc.setPrimFieldValues(obj, primVals);
}
int objHandle = passHandle;
ObjectStreamField[] fields = desc.getFields(false);
Object[] objVals = new Object[desc.getNumObjFields()];
int numPrimFields = fields.length - objVals.length;
for (int i = 0; i < objVals.length; i++) {
ObjectStreamField f = fields[numPrimFields + i];
objVals[i] = readObject0(f.isUnshared());
if (f.getField() != null) {
handles.markDependency(objHandle, passHandle);
}
}
if (obj != null) {
desc.setObjFieldValues(obj, objVals);
}
passHandle = objHandle;
}
/**
* Reads in and returns IOException that caused serialization to abort.
* All stream state is discarded prior to reading in fatal exception. Sets
* passHandle to fatal exception's handle.
*/
private IOException readFatalException() throws IOException {
if (bin.readByte() != TC_EXCEPTION) {
throw new StreamCorruptedException();
}
clear();
return (IOException) readObject0(false);
}
/**
* If recursion depth is 0, clears internal data structures; otherwise,
* throws a StreamCorruptedException. This method is called when a
* TC_RESET typecode is encountered.
*/
private void handleReset() throws StreamCorruptedException {
if (depth > 0) {
throw new StreamCorruptedException("unexpected reset");
}
clear();
}
/**
* Converts specified span of bytes into float values.
*/
// REMIND: remove once hotspot inlines Float.intBitsToFloat
private static native void bytesToFloats(byte[] src, int srcpos,
float[] dst, int dstpos,
int nfloats);
/**
* Converts specified span of bytes into double values.
*/
// REMIND: remove once hotspot inlines Double.longBitsToDouble
private static native void bytesToDoubles(byte[] src, int srcpos,
double[] dst, int dstpos,
int ndoubles);
/**
* Returns the first non-null class loader (not counting class loaders of
* generated reflection implementation classes) up the execution stack, or
* null if only code from the null class loader is on the stack. This
* method is also called via reflection by the following RMI-IIOP class:
*
* com.sun.corba.se.internal.util.JDKClassLoader
*
* This method should not be removed or its signature changed without
* corresponding modifications to the above class.
*/
// REMIND: change name to something more accurate?
private static native ClassLoader latestUserDefinedLoader();
/**
* Default GetField implementation.
*/
private class GetFieldImpl extends GetField {
/** class descriptor describing serializable fields */
private final ObjectStreamClass desc;
/** primitive field values */
private final byte[] primVals;
/** object field values */
private final Object[] objVals;
/** object field value handles */
private final int[] objHandles;
/**
* Creates GetFieldImpl object for reading fields defined in given
* class descriptor.
*/
GetFieldImpl(ObjectStreamClass desc) {
this.desc = desc;
primVals = new byte[desc.getPrimDataSize()];
objVals = new Object[desc.getNumObjFields()];
objHandles = new int[objVals.length];
}
public ObjectStreamClass getObjectStreamClass() {
return desc;
}
public boolean defaulted(String name) throws IOException {
return (getFieldOffset(name, null) < 0);
}
public boolean get(String name, boolean val) throws IOException {
int off = getFieldOffset(name, Boolean.TYPE);
return (off >= 0) ? Bits.getBoolean(primVals, off) : val;
}
public byte get(String name, byte val) throws IOException {
int off = getFieldOffset(name, Byte.TYPE);
return (off >= 0) ? primVals[off] : val;
}
public char get(String name, char val) throws IOException {
int off = getFieldOffset(name, Character.TYPE);
return (off >= 0) ? Bits.getChar(primVals, off) : val;
}
public short get(String name, short val) throws IOException {
int off = getFieldOffset(name, Short.TYPE);
return (off >= 0) ? Bits.getShort(primVals, off) : val;
}
public int get(String name, int val) throws IOException {
int off = getFieldOffset(name, Integer.TYPE);
return (off >= 0) ? Bits.getInt(primVals, off) : val;
}
public float get(String name, float val) throws IOException {
int off = getFieldOffset(name, Float.TYPE);
return (off >= 0) ? Bits.getFloat(primVals, off) : val;
}
public long get(String name, long val) throws IOException {
int off = getFieldOffset(name, Long.TYPE);
return (off >= 0) ? Bits.getLong(primVals, off) : val;
}
public double get(String name, double val) throws IOException {
int off = getFieldOffset(name, Double.TYPE);
return (off >= 0) ? Bits.getDouble(primVals, off) : val;
}
public Object get(String name, Object val) throws IOException {
int off = getFieldOffset(name, Object.class);
if (off >= 0) {
int objHandle = objHandles[off];
handles.markDependency(passHandle, objHandle);
return (handles.lookupException(objHandle) == null) ?
objVals[off] : null;
} else {
return val;
}
}
/**
* Reads primitive and object field values from stream.
*/
void readFields() throws IOException {
bin.readFully(primVals, 0, primVals.length, false);
int oldHandle = passHandle;
ObjectStreamField[] fields = desc.getFields(false);
int numPrimFields = fields.length - objVals.length;
for (int i = 0; i < objVals.length; i++) {
objVals[i] =
readObject0(fields[numPrimFields + i].isUnshared());
objHandles[i] = passHandle;
}
passHandle = oldHandle;
}
/**
* Returns offset of field with given name and type. A specified type
* of null matches all types, Object.class matches all non-primitive
* types, and any other non-null type matches assignable types only.
* If no matching field is found in the (incoming) class
* descriptor but a matching field is present in the associated local
* class descriptor, returns -1. Throws IllegalArgumentException if
* neither incoming nor local class descriptor contains a match.
*/
private int getFieldOffset(String name, Class type) {
ObjectStreamField field = desc.getField(name, type);
if (field != null) {
return field.getOffset();
} else if (desc.getLocalDesc().getField(name, type) != null) {
return -1;
} else {
throw new IllegalArgumentException("no such field");
}
}
}
/**
* Prioritized list of callbacks to be performed once object graph has been
* completely deserialized.
*/
private static class ValidationList {
private static class Callback {
final ObjectInputValidation obj;
final int priority;
Callback next;
Callback(ObjectInputValidation obj, int priority, Callback next) {
this.obj = obj;
this.priority = priority;
this.next = next;
}
}
/** linked list of callbacks */
private Callback list;
/**
* Creates new (empty) ValidationList.
*/
ValidationList() {
}
/**
* Registers callback. Throws InvalidObjectException if callback
* object is null.
*/
void register(ObjectInputValidation obj, int priority)
throws InvalidObjectException
{
if (obj == null) {
throw new InvalidObjectException("null callback");
}
Callback prev = null, cur = list;
while (cur != null && priority < cur.priority) {
prev = cur;
cur = cur.next;
}
if (prev != null) {
prev.next = new Callback(obj, priority, cur);
} else {
list = new Callback(obj, priority, list);
}
}
/**
* Invokes all registered callbacks and clears the callback list.
* Callbacks with higher priorities are called first; those with equal
* priorities may be called in any order. If any of the callbacks
* throws an InvalidObjectException, the callback process is terminated
* and the exception propagated upwards.
*/
void doCallbacks() throws InvalidObjectException {
try {
while (list != null) {
list.obj.validateObject();
list = list.next;
}
} catch (InvalidObjectException ex) {
list = null;
throw ex;
}
}
/**
* Resets the callback list to its initial (empty) state.
*/
public void clear() {
list = null;
}
}
/**
* Input stream supporting single-byte peek operations.
*/
private static class PeekInputStream extends InputStream {
/** underlying stream */
private final InputStream in;
/** peeked byte */
private int peekb = -1;
/**
* Creates new PeekInputStream on top of given underlying stream.
*/
PeekInputStream(InputStream in) {
this.in = in;
}
/**
* Peeks at next byte value in stream. Similar to read(), except
* that it does not consume the read value.
*/
int peek() throws IOException {
return (peekb >= 0) ? peekb : (peekb = in.read());
}
public int read() throws IOException {
if (peekb >= 0) {
int v = peekb;
peekb = -1;
return v;
} else {
return in.read();
}
}
public int read(byte[] b, int off, int len) throws IOException {
if (len == 0) {
return 0;
} else if (peekb < 0) {
return in.read(b, off, len);
} else {
b[off++] = (byte) peekb;
len--;
peekb = -1;
int n = in.read(b, off, len);
return (n >= 0) ? (n + 1) : 1;
}
}
void readFully(byte[] b, int off, int len) throws IOException {
int n = 0;
while (n < len) {
int count = read(b, off + n, len - n);
if (count < 0) {
throw new EOFException();
}
n += count;
}
}
public long skip(long n) throws IOException {
if (n <= 0) {
return 0;
}
int skipped = 0;
if (peekb >= 0) {
peekb = -1;
skipped++;
n--;
}
return skipped + skip(n);
}
public int available() throws IOException {
return in.available() + ((peekb >= 0) ? 1 : 0);
}
public void close() throws IOException {
in.close();
}
}
/**
* Input stream with two modes: in default mode, inputs data written in the
* same format as DataOutputStream; in "block data" mode, inputs data
* bracketed by block data markers (see object serialization specification
* for details). Buffering depends on block data mode: when in default
* mode, no data is buffered in advance; when in block data mode, all data
* for the current data block is read in at once (and buffered).
*/
private class BlockDataInputStream
extends InputStream implements DataInput
{
/** maximum data block length */
private static final int MAX_BLOCK_SIZE = 1024;
/** maximum data block header length */
private static final int MAX_HEADER_SIZE = 5;
/** (tunable) length of char buffer (for reading strings) */
private static final int CHAR_BUF_SIZE = 256;
/** readBlockHeader() return value indicating header read may block */
private static final int HEADER_BLOCKED = -2;
/** buffer for reading general/block data */
private final byte[] buf = new byte[MAX_BLOCK_SIZE];
/** buffer for reading block data headers */
private final byte[] hbuf = new byte[MAX_HEADER_SIZE];
/** char buffer for fast string reads */
private final char[] cbuf = new char[CHAR_BUF_SIZE];
/** block data mode */
private boolean blkmode = false;
// block data state fields; values meaningful only when blkmode true
/** current offset into buf */
private int pos = 0;
/** end offset of valid data in buf, or -1 if no more block data */
private int end = -1;
/** number of bytes in current block yet to be read from stream */
private int unread = 0;
/** underlying stream (wrapped in peekable filter stream) */
private final PeekInputStream in;
/** loopback stream (for data reads that span data blocks) */
private final DataInputStream din;
/**
* Creates new BlockDataInputStream on top of given underlying stream.
* Block data mode is turned off by default.
*/
BlockDataInputStream(InputStream in) {
this.in = new PeekInputStream(in);
din = new DataInputStream(this);
}
/**
* Sets block data mode to the given mode (true == on, false == off)
* and returns the previous mode value. If the new mode is the same as
* the old mode, no action is taken. Throws IllegalStateException if
* block data mode is being switched from on to off while unconsumed
* block data is still present in the stream.
*/
boolean setBlockDataMode(boolean newmode) throws IOException {
if (blkmode == newmode) {
return blkmode;
}
if (newmode) {
pos = 0;
end = 0;
unread = 0;
} else if (pos < end) {
throw new IllegalStateException("unread block data");
}
blkmode = newmode;
return !blkmode;
}
/**
* Returns true if the stream is currently in block data mode, false
* otherwise.
*/
boolean getBlockDataMode() {
return blkmode;
}
/**
* If in block data mode, skips to the end of the current group of data
* blocks (but does not unset block data mode). If not in block data
* mode, throws an IllegalStateException.
*/
void skipBlockData() throws IOException {
if (!blkmode) {
throw new IllegalStateException("not in block data mode");
}
while (end >= 0) {
refill();
}
}
/**
* Attempts to read in the next block data header (if any). If
* canBlock is false and a full header cannot be read without possibly
* blocking, returns HEADER_BLOCKED, else if the next element in the
* stream is a block data header, returns the block data length
* specified by the header, else returns -1.
*/
private int readBlockHeader(boolean canBlock) throws IOException {
if (defaultDataEnd) {
/*
* Fix for 4360508: stream is currently at the end of a field
* value block written via default serialization; since there
* is no terminating TC_ENDBLOCKDATA tag, simulate
* end-of-custom-data behavior explicitly.
*/
return -1;
}
try {
for (;;) {
int avail = canBlock ? Integer.MAX_VALUE : in.available();
if (avail == 0) {
return HEADER_BLOCKED;
}
int tc = in.peek();
switch (tc) {
case TC_BLOCKDATA:
if (avail < 2) {
return HEADER_BLOCKED;
}
in.readFully(hbuf, 0, 2);
return hbuf[1] & 0xFF;
case TC_BLOCKDATALONG:
if (avail < 5) {
return HEADER_BLOCKED;
}
in.readFully(hbuf, 0, 5);
int len = Bits.getInt(hbuf, 1);
if (len < 0) {
throw new StreamCorruptedException(
"illegal block data header length");
}
return len;
/*
* TC_RESETs may occur in between data blocks.
* Unfortunately, this case must be parsed at a lower
* level than other typecodes, since primitive data
* reads may span data blocks separated by a TC_RESET.
*/
case TC_RESET:
in.read();
handleReset();
break;
default:
if (tc >= 0 && (tc < TC_BASE || tc > TC_MAX)) {
throw new StreamCorruptedException();
}
return -1;
}
}
} catch (EOFException ex) {
throw new StreamCorruptedException(
"unexpected EOF while reading block data header");
}
}
/**
* Refills internal buffer buf with block data. Any data in buf at the
* time of the call is considered consumed. Sets the pos, end, and
* unread fields to reflect the new amount of available block data; if
* the next element in the stream is not a data block, sets pos and
* unread to 0 and end to -1.
*/
private void refill() throws IOException {
try {
do {
pos = 0;
if (unread > 0) {
int n =
in.read(buf, 0, Math.min(unread, MAX_BLOCK_SIZE));
if (n >= 0) {
end = n;
unread -= n;
} else {
throw new StreamCorruptedException(
"unexpected EOF in middle of data block");
}
} else {
int n = readBlockHeader(true);
if (n >= 0) {
end = 0;
unread = n;
} else {
end = -1;
unread = 0;
}
}
} while (pos == end);
} catch (IOException ex) {
pos = 0;
end = -1;
unread = 0;
throw ex;
}
}
/**
* If in block data mode, returns the number of unconsumed bytes
* remaining in the current data block. If not in block data mode,
* throws an IllegalStateException.
*/
int currentBlockRemaining() {
if (blkmode) {
return (end >= 0) ? (end - pos) + unread : 0;
} else {
throw new IllegalStateException();
}
}
/**
* Peeks at (but does not consume) and returns the next byte value in
* the stream, or -1 if the end of the stream/block data (if in block
* data mode) has been reached.
*/
int peek() throws IOException {
if (blkmode) {
if (pos == end) {
refill();
}
return (end >= 0) ? (buf[pos] & 0xFF) : -1;
} else {
return in.peek();
}
}
/**
* Peeks at (but does not consume) and returns the next byte value in
* the stream, or throws EOFException if end of stream/block data has
* been reached.
*/
byte peekByte() throws IOException {
int val = peek();
if (val < 0) {
throw new EOFException();
}
return (byte) val;
}
/* ----------------- generic input stream methods ------------------ */
/*
* The following methods are equivalent to their counterparts in
* InputStream, except that they interpret data block boundaries and
* read the requested data from within data blocks when in block data
* mode.
*/
public int read() throws IOException {
if (blkmode) {
if (pos == end) {
refill();
}
return (end >= 0) ? (buf[pos++] & 0xFF) : -1;
} else {
return in.read();
}
}
public int read(byte[] b, int off, int len) throws IOException {
return read(b, off, len, false);
}
public long skip(long len) throws IOException {
long remain = len;
while (remain > 0) {
if (blkmode) {
if (pos == end) {
refill();
}
if (end < 0) {
break;
}
int nread = (int) Math.min(remain, end - pos);
remain -= nread;
pos += nread;
} else {
int nread = (int) Math.min(remain, MAX_BLOCK_SIZE);
if ((nread = in.read(buf, 0, nread)) < 0) {
break;
}
remain -= nread;
}
}
return len - remain;
}
public int available() throws IOException {
if (blkmode) {
if ((pos == end) && (unread == 0)) {
int n;
while ((n = readBlockHeader(false)) == 0) ;
switch (n) {
case HEADER_BLOCKED:
break;
case -1:
pos = 0;
end = -1;
break;
default:
pos = 0;
end = 0;
unread = n;
break;
}
}
// avoid unnecessary call to in.available() if possible
int unreadAvail = (unread > 0) ?
Math.min(in.available(), unread) : 0;
return (end >= 0) ? (end - pos) + unreadAvail : 0;
} else {
return in.available();
}
}
public void close() throws IOException {
if (blkmode) {
pos = 0;
end = -1;
unread = 0;
}
in.close();
}
/**
* Attempts to read len bytes into byte array b at offset off. Returns
* the number of bytes read, or -1 if the end of stream/block data has
* been reached. If copy is true, reads values into an intermediate
* buffer before copying them to b (to avoid exposing a reference to
* b).
*/
int read(byte[] b, int off, int len, boolean copy) throws IOException {
if (len == 0) {
return 0;
} else if (blkmode) {
if (pos == end) {
refill();
}
if (end < 0) {
return -1;
}
int nread = Math.min(len, end - pos);
System.arraycopy(buf, pos, b, off, nread);
pos += nread;
return nread;
} else if (copy) {
int nread = in.read(buf, 0, Math.min(len, MAX_BLOCK_SIZE));
if (nread > 0) {
System.arraycopy(buf, 0, b, off, nread);
}
return nread;
} else {
return in.read(b, off, len);
}
}
/* ----------------- primitive data input methods ------------------ */
/*
* The following methods are equivalent to their counterparts in
* DataInputStream, except that they interpret data block boundaries
* and read the requested data from within data blocks when in block
* data mode.
*/
public void readFully(byte[] b) throws IOException {
readFully(b, 0, b.length, false);
}
public void readFully(byte[] b, int off, int len) throws IOException {
readFully(b, off, len, false);
}
public void readFully(byte[] b, int off, int len, boolean copy)
throws IOException
{
while (len > 0) {
int n = read(b, off, len, copy);
if (n < 0) {
throw new EOFException();
}
off += n;
len -= n;
}
}
public int skipBytes(int n) throws IOException {
return din.skipBytes(n);
}
public boolean readBoolean() throws IOException {
int v = read();
if (v < 0) {
throw new EOFException();
}
return (v != 0);
}
public byte readByte() throws IOException {
int v = read();
if (v < 0) {
throw new EOFException();
}
return (byte) v;
}
public int readUnsignedByte() throws IOException {
int v = read();
if (v < 0) {
throw new EOFException();
}
return v;
}
public char readChar() throws IOException {
if (!blkmode) {
pos = 0;
in.readFully(buf, 0, 2);
} else if (end - pos < 2) {
return din.readChar();
}
char v = Bits.getChar(buf, pos);
pos += 2;
return v;
}
public short readShort() throws IOException {
if (!blkmode) {
pos = 0;
in.readFully(buf, 0, 2);
} else if (end - pos < 2) {
return din.readShort();
}
short v = Bits.getShort(buf, pos);
pos += 2;
return v;
}
public int readUnsignedShort() throws IOException {
if (!blkmode) {
pos = 0;
in.readFully(buf, 0, 2);
} else if (end - pos < 2) {
return din.readUnsignedShort();
}
int v = Bits.getShort(buf, pos) & 0xFFFF;
pos += 2;
return v;
}
public int readInt() throws IOException {
if (!blkmode) {
pos = 0;
in.readFully(buf, 0, 4);
} else if (end - pos < 4) {
return din.readInt();
}
int v = Bits.getInt(buf, pos);
pos += 4;
return v;
}
public float readFloat() throws IOException {
if (!blkmode) {
pos = 0;
in.readFully(buf, 0, 4);
} else if (end - pos < 4) {
return din.readFloat();
}
float v = Bits.getFloat(buf, pos);
pos += 4;
return v;
}
public long readLong() throws IOException {
if (!blkmode) {
pos = 0;
in.readFully(buf, 0, 8);
} else if (end - pos < 8) {
return din.readLong();
}
long v = Bits.getLong(buf, pos);
pos += 8;
return v;
}
public double readDouble() throws IOException {
if (!blkmode) {
pos = 0;
in.readFully(buf, 0, 8);
} else if (end - pos < 8) {
return din.readDouble();
}
double v = Bits.getDouble(buf, pos);
pos += 8;
return v;
}
public String readUTF() throws IOException {
return readUTFBody(readUnsignedShort());
}
public String readLine() throws IOException {
return din.readLine(); // deprecated, not worth optimizing
}
/* -------------- primitive data array input methods --------------- */
/*
* The following methods read in spans of primitive data values.
* Though equivalent to calling the corresponding primitive read
* methods repeatedly, these methods are optimized for reading groups
* of primitive data values more efficiently.
*/
void readBooleans(boolean[] v, int off, int len) throws IOException {
int stop, endoff = off + len;
while (off < endoff) {
if (!blkmode) {
int span = Math.min(endoff - off, MAX_BLOCK_SIZE);
in.readFully(buf, 0, span);
stop = off + span;
pos = 0;
} else if (end - pos < 1) {
v[off++] = din.readBoolean();
continue;
} else {
stop = Math.min(endoff, off + end - pos);
}
while (off < stop) {
v[off++] = Bits.getBoolean(buf, pos++);
}
}
}
void readChars(char[] v, int off, int len) throws IOException {
int stop, endoff = off + len;
while (off < endoff) {
if (!blkmode) {
int span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 1);
in.readFully(buf, 0, span << 1);
stop = off + span;
pos = 0;
} else if (end - pos < 2) {
v[off++] = din.readChar();
continue;
} else {
stop = Math.min(endoff, off + ((end - pos) >> 1));
}
while (off < stop) {
v[off++] = Bits.getChar(buf, pos);
pos += 2;
}
}
}
void readShorts(short[] v, int off, int len) throws IOException {
int stop, endoff = off + len;
while (off < endoff) {
if (!blkmode) {
int span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 1);
in.readFully(buf, 0, span << 1);
stop = off + span;
pos = 0;
} else if (end - pos < 2) {
v[off++] = din.readShort();
continue;
} else {
stop = Math.min(endoff, off + ((end - pos) >> 1));
}
while (off < stop) {
v[off++] = Bits.getShort(buf, pos);
pos += 2;
}
}
}
void readInts(int[] v, int off, int len) throws IOException {
int stop, endoff = off + len;
while (off < endoff) {
if (!blkmode) {
int span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 2);
in.readFully(buf, 0, span << 2);
stop = off + span;
pos = 0;
} else if (end - pos < 4) {
v[off++] = din.readInt();
continue;
} else {
stop = Math.min(endoff, off + ((end - pos) >> 2));
}
while (off < stop) {
v[off++] = Bits.getInt(buf, pos);
pos += 4;
}
}
}
void readFloats(float[] v, int off, int len) throws IOException {
int span, endoff = off + len;
while (off < endoff) {
if (!blkmode) {
span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 2);
in.readFully(buf, 0, span << 2);
pos = 0;
} else if (end - pos < 4) {
v[off++] = din.readFloat();
continue;
} else {
span = Math.min(endoff - off, ((end - pos) >> 2));
}
bytesToFloats(buf, pos, v, off, span);
off += span;
pos += span << 2;
}
}
void readLongs(long[] v, int off, int len) throws IOException {
int stop, endoff = off + len;
while (off < endoff) {
if (!blkmode) {
int span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 3);
in.readFully(buf, 0, span << 3);
stop = off + span;
pos = 0;
} else if (end - pos < 8) {
v[off++] = din.readLong();
continue;
} else {
stop = Math.min(endoff, off + ((end - pos) >> 3));
}
while (off < stop) {
v[off++] = Bits.getLong(buf, pos);
pos += 8;
}
}
}
void readDoubles(double[] v, int off, int len) throws IOException {
int span, endoff = off + len;
while (off < endoff) {
if (!blkmode) {
span = Math.min(endoff - off, MAX_BLOCK_SIZE >> 3);
in.readFully(buf, 0, span << 3);
pos = 0;
} else if (end - pos < 8) {
v[off++] = din.readDouble();
continue;
} else {
span = Math.min(endoff - off, ((end - pos) >> 3));
}
bytesToDoubles(buf, pos, v, off, span);
off += span;
pos += span << 3;
}
}
/**
* Reads in string written in "long" UTF format. "Long" UTF format is
* identical to standard UTF, except that it uses an 8 byte header
* (instead of the standard 2 bytes) to convey the UTF encoding length.
*/
String readLongUTF() throws IOException {
return readUTFBody(readLong());
}
/**
* Reads in the "body" (i.e., the UTF representation minus the 2-byte
* or 8-byte length header) of a UTF encoding, which occupies the next
* utflen bytes.
*/
private String readUTFBody(long utflen) throws IOException {
StringBuffer sbuf = new StringBuffer();
if (!blkmode) {
end = pos = 0;
}
while (utflen > 0) {
int avail = end - pos;
if (avail >= 3 || (long) avail == utflen) {
utflen -= readUTFSpan(sbuf, utflen);
} else {
if (blkmode) {
// near block boundary, read one byte at a time
utflen -= readUTFChar(sbuf, utflen);
} else {
// shift and refill buffer manually
if (avail > 0) {
System.arraycopy(buf, pos, buf, 0, avail);
}
pos = 0;
end = (int) Math.min(MAX_BLOCK_SIZE, utflen);
in.readFully(buf, avail, end - avail);
}
}
}
return sbuf.toString();
}
/**
* Reads span of UTF-encoded characters out of internal buffer
* (starting at offset pos and ending at or before offset end),
* consuming no more than utflen bytes. Appends read characters to
* sbuf. Returns the number of bytes consumed.
*/
private long readUTFSpan(StringBuffer sbuf, long utflen)
throws IOException
{
int cpos = 0;
int start = pos;
int avail = Math.min(end - pos, CHAR_BUF_SIZE);
// stop short of last char unless all of utf bytes in buffer
int stop = pos + ((utflen > avail) ? avail - 2 : (int) utflen);
boolean outOfBounds = false;
try {
while (pos < stop) {
int b1, b2, b3;
b1 = buf[pos++] & 0xFF;
switch (b1 >> 4) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
case 6:
case 7: // 1 byte format: 0xxxxxxx
cbuf[cpos++] = (char) b1;
break;
case 12:
case 13: // 2 byte format: 110xxxxx 10xxxxxx
b2 = buf[pos++];
if ((b2 & 0xC0) != 0x80) {
throw new UTFDataFormatException();
}
cbuf[cpos++] = (char) (((b1 & 0x1F) << 6) |
((b2 & 0x3F) << 0));
break;
case 14: // 3 byte format: 1110xxxx 10xxxxxx 10xxxxxx
b3 = buf[pos + 1];
b2 = buf[pos + 0];
pos += 2;
if ((b2 & 0xC0) != 0x80 || (b3 & 0xC0) != 0x80) {
throw new UTFDataFormatException();
}
cbuf[cpos++] = (char) (((b1 & 0x0F) << 12) |
((b2 & 0x3F) << 6) |
((b3 & 0x3F) << 0));
break;
default: // 10xx xxxx, 1111 xxxx
throw new UTFDataFormatException();
}
}
} catch (ArrayIndexOutOfBoundsException ex) {
outOfBounds = true;
} finally {
if (outOfBounds || (pos - start) > utflen) {
/*
* Fix for 4450867: if a malformed utf char causes the
* conversion loop to scan past the expected end of the utf
* string, only consume the expected number of utf bytes.
*/
pos = start + (int) utflen;
throw new UTFDataFormatException();
}
}
sbuf.append(cbuf, 0, cpos);
return pos - start;
}
/**
* Reads in single UTF-encoded character one byte at a time, appends
* the character to sbuf, and returns the number of bytes consumed.
* This method is used when reading in UTF strings written in block
* data mode to handle UTF-encoded characters which (potentially)
* straddle block-data boundaries.
*/
private int readUTFChar(StringBuffer sbuf, long utflen)
throws IOException
{
int b1, b2, b3;
b1 = readByte() & 0xFF;
switch (b1 >> 4) {
case 0:
case 1:
case 2:
case 3:
case 4:
case 5:
case 6:
case 7: // 1 byte format: 0xxxxxxx
sbuf.append((char) b1);
return 1;
case 12:
case 13: // 2 byte format: 110xxxxx 10xxxxxx
if (utflen < 2) {
throw new UTFDataFormatException();
}
b2 = readByte();
if ((b2 & 0xC0) != 0x80) {
throw new UTFDataFormatException();
}
sbuf.append((char) (((b1 & 0x1F) << 6) |
((b2 & 0x3F) << 0)));
return 2;
case 14: // 3 byte format: 1110xxxx 10xxxxxx 10xxxxxx
if (utflen < 3) {
if (utflen == 2) {
readByte(); // consume remaining byte
}
throw new UTFDataFormatException();
}
b2 = readByte();
b3 = readByte();
if ((b2 & 0xC0) != 0x80 || (b3 & 0xC0) != 0x80) {
throw new UTFDataFormatException();
}
sbuf.append((char) (((b1 & 0x0F) << 12) |
((b2 & 0x3F) << 6) |
((b3 & 0x3F) << 0)));
return 3;
default: // 10xx xxxx, 1111 xxxx
throw new UTFDataFormatException();
}
}
}
/**
* Unsynchronized table which tracks wire handle to object mappings, as
* well as ClassNotFoundExceptions associated with deserialized objects.
* This class implements an exception-propagation algorithm for
* determining which objects should have ClassNotFoundExceptions associated
* with them, taking into account cycles and discontinuities (e.g., skipped
* fields) in the object graph.
*
* <p>General use of the table is as follows: during deserialization, a
* given object is first assigned a handle by calling the assign method.
* This method leaves the assigned handle in an "open" state, wherein
* dependencies on the exception status of other handles can be registered
* by calling the markDependency method, or an exception can be directly
* associated with the handle by calling markException. When a handle is
* tagged with an exception, the HandleTable assumes responsibility for
* propagating the exception to any other objects which depend
* (transitively) on the exception-tagged object.
*
* <p>Once all exception information/dependencies for the handle have been
* registered, the handle should be "closed" by calling the finish method
* on it. The act of finishing a handle allows the exception propagation
* algorithm to aggressively prune dependency links, lessening the
* performance/memory impact of exception tracking.
*
* <p>Note that the exception propagation algorithm used depends on handles
* being assigned/finished in LIFO order; however, for simplicity as well
* as memory conservation, it does not enforce this constraint.
*/
// REMIND: add full description of exception propagation algorithm?
private static class HandleTable {
/* status codes indicating whether object has associated exception */
private static final byte STATUS_OK = 1;
private static final byte STATUS_UNKNOWN = 2;
private static final byte STATUS_EXCEPTION = 3;
/** array mapping handle -> object status */
byte[] status;
/** array mapping handle -> object/exception (depending on status) */
Object[] entries;
/** array mapping handle -> list of dependent handles (if any) */
HandleList[] deps;
/** lowest unresolved dependency */
int lowDep = -1;
/** number of handles in table */
int size = 0;
/**
* Creates handle table with the given initial capacity.
*/
HandleTable(int initialCapacity) {
status = new byte[initialCapacity];
entries = new Object[initialCapacity];
deps = new HandleList[initialCapacity];
}
/**
* Assigns next available handle to given object, and returns assigned
* handle. Once object has been completely deserialized (and all
* dependencies on other objects identified), the handle should be
* "closed" by passing it to finish().
*/
int assign(Object obj) {
if (size >= entries.length) {
grow();
}
status[size] = STATUS_UNKNOWN;
entries[size] = obj;
return size++;
}
/**
* Registers a dependency (in exception status) of one handle on
* another. The dependent handle must be "open" (i.e., assigned, but
* not finished yet). No action is taken if either dependent or target
* handle is NULL_HANDLE.
*/
void markDependency(int dependent, int target) {
if (dependent == NULL_HANDLE || target == NULL_HANDLE) {
return;
}
switch (status[dependent]) {
case STATUS_UNKNOWN:
switch (status[target]) {
case STATUS_OK:
// ignore dependencies on objs with no exception
break;
case STATUS_EXCEPTION:
// eagerly propagate exception
markException(dependent,
(ClassNotFoundException) entries[target]);
break;
case STATUS_UNKNOWN:
// add to dependency list of target
if (deps[target] == null) {
deps[target] = new HandleList();
}
deps[target].add(dependent);
// remember lowest unresolved target seen
if (lowDep < 0 || lowDep > target) {
lowDep = target;
}
break;
default:
throw new InternalError();
}
break;
case STATUS_EXCEPTION:
break;
default:
throw new InternalError();
}
}
/**
* Associates a ClassNotFoundException (if one not already associated)
* with the currently active handle and propagates it to other
* referencing objects as appropriate. The specified handle must be
* "open" (i.e., assigned, but not finished yet).
*/
void markException(int handle, ClassNotFoundException ex) {
switch (status[handle]) {
case STATUS_UNKNOWN:
status[handle] = STATUS_EXCEPTION;
entries[handle] = ex;
// propagate exception to dependents
HandleList dlist = deps[handle];
if (dlist != null) {
int ndeps = dlist.size();
for (int i = 0; i < ndeps; i++) {
markException(dlist.get(i), ex);
}
deps[handle] = null;
}
break;
case STATUS_EXCEPTION:
break;
default:
throw new InternalError();
}
}
/**
* Marks given handle as finished, meaning that no new dependencies
* will be marked for handle. Calls to the assign and finish methods
* must occur in LIFO order.
*/
void finish(int handle) {
int end;
if (lowDep < 0) {
// no pending unknowns, only resolve current handle
end = handle + 1;
} else if (lowDep >= handle) {
// pending unknowns now clearable, resolve all upward handles
end = size;
lowDep = -1;
} else {
// unresolved backrefs present, can't resolve anything yet
return;
}
// change STATUS_UNKNOWN -> STATUS_OK in selected span of handles
for (int i = handle; i < end; i++) {
switch (status[i]) {
case STATUS_UNKNOWN:
status[i] = STATUS_OK;
deps[i] = null;
break;
case STATUS_OK:
case STATUS_EXCEPTION:
break;
default:
throw new InternalError();
}
}
}
/**
* Assigns a new object to the given handle. The object previously
* associated with the handle is forgotten. This method has no effect
* if the given handle already has an exception associated with it.
* This method may be called at any time after the handle is assigned.
*/
void setObject(int handle, Object obj) {
switch (status[handle]) {
case STATUS_UNKNOWN:
case STATUS_OK:
entries[handle] = obj;
break;
case STATUS_EXCEPTION:
break;
default:
throw new InternalError();
}
}
/**
* Looks up and returns object associated with the given handle.
* Returns null if the given handle is NULL_HANDLE, or if it has an
* associated ClassNotFoundException.
*/
Object lookupObject(int handle) {
return (handle != NULL_HANDLE &&
status[handle] != STATUS_EXCEPTION) ?
entries[handle] : null;
}
/**
* Looks up and returns ClassNotFoundException associated with the
* given handle. Returns null if the given handle is NULL_HANDLE, or
* if there is no ClassNotFoundException associated with the handle.
*/
ClassNotFoundException lookupException(int handle) {
return (handle != NULL_HANDLE &&
status[handle] == STATUS_EXCEPTION) ?
(ClassNotFoundException) entries[handle] : null;
}
/**
* Resets table to its initial state.
*/
void clear() {
Arrays.fill(status, 0, size, (byte) 0);
Arrays.fill(entries, 0, size, null);
Arrays.fill(deps, 0, size, null);
lowDep = -1;
size = 0;
}
/**
* Returns number of handles registered in table.
*/
int size() {
return size;
}
/**
* Expands capacity of internal arrays.
*/
private void grow() {
int newCapacity = (entries.length << 1) + 1;
byte[] newStatus = new byte[newCapacity];
Object[] newEntries = new Object[newCapacity];
HandleList[] newDeps = new HandleList[newCapacity];
System.arraycopy(status, 0, newStatus, 0, size);
System.arraycopy(entries, 0, newEntries, 0, size);
System.arraycopy(deps, 0, newDeps, 0, size);
status = newStatus;
entries = newEntries;
deps = newDeps;
}
/**
* Simple growable list of (integer) handles.
*/
private static class HandleList {
private int[] list = new int[4];
private int size = 0;
public HandleList() {
}
public void add(int handle) {
if (size >= list.length) {
int[] newList = new int[list.length << 1];
System.arraycopy(list, 0, newList, 0, list.length);
list = newList;
}
list[size++] = handle;
}
public int get(int index) {
if (index >= size) {
throw new ArrayIndexOutOfBoundsException();
}
return list[index];
}
public int size() {
return size;
}
}
}
}
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