File	Doc	Category	Size	Date	Package
Class.java	API Doc	J2ME MIDP 2.0	13308	Thu Nov 07 12:02:26 GMT 2002	java.lang

Class

• java.lang.Object

Fields Summary
private transient Object	vmClass
private int	status
private Thread	thread
private static final int	VERIFIED
private static final int	IN_PROGRESS
private static final int	INITIALIZED
private static final int	ERROR

Constructors Summary
private Class()

Methods Summary
public static native java.lang.Class	forName(java.lang.String className) Returns the Class object associated with the class with the given string name. Given the fully-qualified name for a class or interface, this method attempts to locate, load and link the class. If it succeeds, returns the Class object representing the class. If it fails, the method throws a ClassNotFoundException. For example, the following code fragment returns the runtime Class descriptor for the class named java.lang.Thread: Class t = Class.forName("java.lang.Thread") param className the fully qualified name of the desired class. return the Class descriptor for the class with the specified name. exception ClassNotFoundException if the class could not be found. since JDK1.0
public native java.lang.String	getName() Returns the fully-qualified name of the entity (class, interface, array class, primitive type, or void) represented by this Class object, as a String. If this Class object represents a class of arrays, then the internal form of the name consists of the name of the element type in Java signature format, preceded by one or more "[" characters representing the depth of array nesting. Thus: (new Object[3]).getClass().getName() returns "[Ljava.lang.Object;" and: (new int[3][4][5][6][7][8][9]).getClass().getName() returns "[[[[[[[I". The encoding of element type names is as follows: B byte C char D double F float I int J long Lclassname; class or interface S short Z boolean The class or interface name classname is given in fully qualified form as shown in the example above. return the fully qualified name of the class or interface represented by this object.
public java.io.InputStream	getResourceAsStream(java.lang.String name) Finds a resource with a given name. This method returns null if no resource with this name is found. The rules for searching resources associated with a given class are profile specific. param name name of the desired resource return a java.io.InputStream object. since JDK1.1 try { if (name.length() > 0 && name.charAt(0) == '/") { name = name.substring(1); } else { String className = this.getName(); int dotIndex = className.lastIndexOf('."); if (dotIndex >= 0) { name = className.substring(0, dotIndex + 1).replace('.", '/") + name; } } return new ResourceInputStream(name); } catch (java.io.IOException x) { return null; }
private native java.lang.Class	getSuperclass() Returns the Class representing the superclass of the entity (class, interface, primitive type or void) represented by this Class. If this Class represents either the Object class, an interface, a primitive type, or void, then null is returned. If this object represents an array class then the Class object representing the Object class is returned. Note that this method is not supported by CLDC. We have made the method private, since it is needed by our implementation. return the superclass of the class represented by this object.
void	initialize() // Native for invoking <clinit> verify(); // Implements the 11 step program detailed in Java Language Specification 12.4.2 // Step 1 synchronized (this) { // Step 2 while (status == IN_PROGRESS && thread != Thread.currentThread()) { try{ wait(); } catch (InterruptedException e) { } } // Step 3 if (status == IN_PROGRESS && thread == Thread.currentThread()) return; // Step 4 if (status == INITIALIZED) return; // Step 5 if (status == ERROR) throw new Error("NoClassDefFoundError:"+getName()); /* Note: CLDC 1.0 does not have NoClassDefFoundError class */ // Step 6 status = IN_PROGRESS; thread = Thread.currentThread(); } try { // Step 7 Class s = getSuperclass(); if (s != null && s.status != INITIALIZED) { // The test of s.status is not part of the spec, but it saves us // doing a lot of work in the most common case. s.initialize(); } // Step 8 invoke_clinit(); // Step 9 synchronized (this) { status = INITIALIZED; thread = null; notifyAll(); } } catch(Throwable e) { // Step 10 and 11 synchronized (this) { status = ERROR; thread = null; notifyAll(); throwError(e); } }
private native void	invoke_clinit()
private native void	invoke_verifier()
public native boolean	isArray() Determines if this Class object represents an array class. return true if this object represents an array class; false otherwise. since JDK1.1
public native boolean	isAssignableFrom(java.lang.Class cls) Determines if the class or interface represented by this Class object is either the same as, or is a superclass or superinterface of, the class or interface represented by the specified Class parameter. It returns true if so; otherwise it returns false. If this Class object represents a primitive type, this method returns true if the specified Class parameter is exactly this Class object; otherwise it returns false. Specifically, this method tests whether the type represented by the specified Class parameter can be converted to the type represented by this Class object via an identity conversion or via a widening reference conversion. See The Java Language Specification, sections 5.1.1 and 5.1.4 , for details. param cls the Class object to be checked return the boolean value indicating whether objects of the type cls can be assigned to objects of this class exception NullPointerException if the specified Class parameter is null. since JDK1.1
public native boolean	isInstance(java.lang.Object obj) Determines if the specified Object is assignment-compatible with the object represented by this Class. This method is the dynamic equivalent of the Java language instanceof operator. The method returns true if the specified Object argument is non-null and can be cast to the reference type represented by this Class object without raising a ClassCastException. It returns false otherwise. Specifically, if this Class object represents a declared class, this method returns true if the specified Object argument is an instance of the represented class (or of any of its subclasses); it returns false otherwise. If this Class object represents an array class, this method returns true if the specified Object argument can be converted to an object of the array class by an identity conversion or by a widening reference conversion; it returns false otherwise. If this Class object represents an interface, this method returns true if the class or any superclass of the specified Object argument implements this interface; it returns false otherwise. If this Class object represents a primitive type, this method returns false. param obj the object to check return true if obj is an instance of this class since JDK1.1
public native boolean	isInterface() Determines if the specified Class object represents an interface type. return true if this object represents an interface; false otherwise.
public native java.lang.Object	newInstance() Creates a new instance of a class. return a newly allocated instance of the class represented by this object. This is done exactly as if by a new expression with an empty argument list. exception IllegalAccessException if the class or initializer is not accessible. exception InstantiationException if an application tries to instantiate an abstract class or an interface, or if the instantiation fails for some other reason. since JDK1.0
private static void	runCustomCode()
private java.lang.Error	throwError(java.lang.Throwable e) throw (e instanceof Error) ? (Error)e : new Error("Static initializer: " + e.getClass().getName() + ", " + e.getMessage());
public java.lang.String	toString() Converts the object to a string. The string representation is the string "class" or "interface", followed by a space, and then by the fully qualified name of the class in the format returned by getName. If this Class object represents a primitive type, this method returns the name of the primitive type. If this Class object represents void this method returns "void". return a string representation of this class object. return (isInterface() ? "interface " : "class ") + getName();
synchronized void	verify() if (status < VERIFIED) { getSuperclass().verify(); invoke_verifier(); status = VERIFIED; }