/*
* Licensed to the Apache Software Foundation (ASF) under one or more
* contributor license agreements. See the NOTICE file distributed with
* this work for additional information regarding copyright ownership.
* The ASF licenses this file to You under the Apache License, Version 2.0
* (the "License"); you may not use this file except in compliance with
* the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package java.io;
import java.nio.channels.FileChannel;
import org.apache.harmony.luni.platform.IFileSystem;
import org.apache.harmony.luni.platform.Platform;
import org.apache.harmony.luni.util.Msg;
import org.apache.harmony.luni.util.Util;
import org.apache.harmony.nio.FileChannelFactory;
/**
* Allows reading from and writing to a file in a random-access manner. This is
* different from the uni-directional sequential access that a
* {@link FileInputStream} or {@link FileOutputStream} provides. If the file is
* opened in read/write mode, write operations are available as well. The
* position of the next read or write operation can be moved forwards and
* backwards after every operation.
*
* @since Android 1.0
*/
public class RandomAccessFile implements DataInput, DataOutput, Closeable {
/**
* The FileDescriptor representing this RandomAccessFile.
*/
private FileDescriptor fd;
private boolean syncMetadata = false;
// The unique file channel associated with this FileInputStream (lazily
// initialized).
private FileChannel channel;
private IFileSystem fileSystem = Platform.getFileSystem();
private boolean isReadOnly;
// BEGIN android-added
private int options;
// END android-added
private static class RepositionLock {
}
private Object repositionLock = new RepositionLock();
// BEGIN android-changed
/**
* Constructs a new {@code RandomAccessFile} based on {@code file} and opens
* it according to the access string in {@code mode}.
* <p><a id="accessmode"/>
* {@code mode} may have one of following values:
* <table border="0">
* <tr>
* <td>{@code "r"}</td>
* <td>The file is opened in read-only mode. An {@code IOException} is
* thrown if any of the {@code write} methods is called.</td>
* </tr>
* <tr>
* <td>{@code "rw"}</td>
* <td>The file is opened for reading and writing. If the file does not
* exist, it will be created.</td>
* </tr>
* <tr>
* <td>{@code "rws"}</td>
* <td>The file is opened for reading and writing. Every change of the
* file's content or metadata must be written synchronously to the target
* device.</td>
* </tr>
* <tr>
* <td>{@code "rwd"}</td>
* <td>The file is opened for reading and writing. Every change of the
* file's content must be written synchronously to the target device.</td>
* </tr>
* </table>
* </p>
* @param file
* the file to open.
* @param mode
* the file access <a href="#accessmode">mode</a>, either {@code
* "r"}, {@code "rw"}, {@code "rws"} or {@code "rwd"}.
* @throws FileNotFoundException
* if the file cannot be opened or created according to {@code
* mode}.
* @throws IllegalArgumentException
* if {@code mode} is not {@code "r"}, {@code "rw"}, {@code
* "rws"} or {@code "rwd"}.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies
* access request according to {@code mode}.
* @see java.lang.SecurityManager#checkRead(FileDescriptor)
* @see java.lang.SecurityManager#checkWrite(FileDescriptor)
* @since Android 1.0
*/
public RandomAccessFile(File file, String mode)
throws FileNotFoundException {
super();
options = 0;
fd = new FileDescriptor();
if (mode.equals("r")) { //$NON-NLS-1$
isReadOnly = true;
fd.readOnly = true;
options = IFileSystem.O_RDONLY;
} else if (mode.equals("rw") || mode.equals("rws") || mode.equals("rwd")) { //$NON-NLS-1$ //$NON-NLS-2$ //$NON-NLS-3$
isReadOnly = false;
options = IFileSystem.O_RDWR;
if (mode.equals("rws")) { //$NON-NLS-1$
// Sync file and metadata with every write
syncMetadata = true;
} else if (mode.equals("rwd")) { //$NON-NLS-1$
// Sync file, but not necessarily metadata
options = IFileSystem.O_RDWRSYNC;
}
} else {
throw new IllegalArgumentException(Msg.getString("K0081")); //$NON-NLS-1$
}
SecurityManager security = System.getSecurityManager();
if (security != null) {
security.checkRead(file.getPath());
if (!isReadOnly) {
security.checkWrite(file.getPath());
}
}
fd.descriptor = fileSystem.open(file.properPath(true), options);
// if we are in "rws" mode, attempt to sync file+metadata
if (syncMetadata) {
try {
fd.sync();
} catch (IOException e) {
// Ignored
}
}
}
// END android-changed
/**
* Constructs a new {@code RandomAccessFile} based on the file named {@code
* fileName} and opens it according to the access string in {@code mode}.
* The file path may be specified absolutely or relative to the system
* property {@code "user.dir"}.
*
* @param fileName
* the name of the file to open.
* @param mode
* the file access <a href="#accessmode">mode</a>, either {@code
* "r"}, {@code "rw"}, {@code "rws"} or {@code "rwd"}.
* @throws FileNotFoundException
* if the file cannot be opened or created according to {@code
* mode}.
* @throws IllegalArgumentException
* if {@code mode} is not {@code "r"}, {@code "rw"}, {@code
* "rws"} or {@code "rwd"}.
* @throws SecurityException
* if a {@code SecurityManager} is installed and it denies
* access request according to {@code mode}.
* @see java.lang.SecurityManager#checkRead(FileDescriptor)
* @see java.lang.SecurityManager#checkWrite(FileDescriptor)
* @since Android 1.0
*/
public RandomAccessFile(String fileName, String mode)
throws FileNotFoundException {
this(new File(fileName), mode);
}
/**
* Closes this file.
*
* @throws IOException
* if an error occurs while closing this file.
* @since Android 1.0
*/
public void close() throws IOException {
// BEGIN android-changed
synchronized (this) {
if (channel != null && channel.isOpen()) {
channel.close();
channel = null;
}
if (fd != null && fd.descriptor >= 0) {
fileSystem.close(fd.descriptor);
fd.descriptor = -1;
}
}
// END android-changed
}
// BEGIN android-changed
/**
* Gets this file's {@link FileChannel} object.
* <p>
* The file channel's {@link FileChannel.#position() position} is the same
* as this file's file pointer offset (see {@link #getFilePointer()}). Any
* changes made to this file's file pointer offset are also visible in the
* file channel's position and vice versa.
* </p>
*
* @return this file's file channel instance.
* @since Android 1.0
*/
public final FileChannel getChannel() {
synchronized(this) {
if(channel == null) {
channel = FileChannelFactory.getFileChannel(this, fd.descriptor,
options);
}
return channel;
}
}
// END android-changed
/**
* Gets this file's {@link FileDescriptor}. This represents the operating
* system resource for this random access file.
*
* @return this file's file descriptor object.
* @throws IOException
* if an error occurs while getting the file descriptor of this
* file.
* @since Android 1.0
*/
public final FileDescriptor getFD() throws IOException {
return fd;
}
/**
* Gets the current position within this file. All reads and
* writes take place at the current file pointer position.
*
* @return the current offset in bytes from the beginning of the file.
*
* @throws IOException
* if an error occurs while getting the file pointer of this
* file.
* @since Android 1.0
*/
public long getFilePointer() throws IOException {
openCheck();
return fileSystem.seek(fd.descriptor, 0L, IFileSystem.SEEK_CUR);
}
/**
* Checks to see if the file is currently open. Returns silently if it is,
* and throws an exception if it is not.
*
* @throws IOException
* the receiver is closed.
*/
private synchronized void openCheck() throws IOException {
if (fd.descriptor < 0) {
throw new IOException();
}
}
/**
* Returns the length of this file in bytes.
*
* @return the file's length in bytes.
* @throws IOException
* if this file is closed or some other I/O error occurs.
* @since Android 1.0
*/
public long length() throws IOException {
openCheck();
synchronized (repositionLock) {
long currentPosition = fileSystem.seek(fd.descriptor, 0L,
IFileSystem.SEEK_CUR);
long endOfFilePosition = fileSystem.seek(fd.descriptor, 0L,
IFileSystem.SEEK_END);
fileSystem.seek(fd.descriptor, currentPosition,
IFileSystem.SEEK_SET);
return endOfFilePosition;
}
}
/**
* Reads a single byte from the current position in this file and returns it
* as an integer in the range from 0 to 255. Returns -1 if the end of the
* file has been reached. Blocks until one byte has been read, the end of
* the file is detected or an exception is thrown.
*
* @return the byte read or -1 if the end of the file has been reached.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @since Android 1.0
*/
public int read() throws IOException {
openCheck();
byte[] bytes = new byte[1];
synchronized (repositionLock) {
long readed = fileSystem.read(fd.descriptor, bytes, 0, 1);
return readed == -1 ? -1 : bytes[0] & 0xff;
}
}
/**
* Reads bytes from the current position in this file and stores them in the
* byte array {@code buffer}. The maximum number of bytes read corresponds
* to the size of {@code buffer}. Blocks until at least one byte has been
* read.
*
* @param buffer
* the byte array in which to store the bytes read.
* @return the number of bytes actually read or -1 if the end of the file
* has been reached.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @since Android 1.0
*/
public int read(byte[] buffer) throws IOException {
return read(buffer, 0, buffer.length);
}
/**
* Reads at most {@code count} bytes from the current position in this file
* and stores them in the byte array {@code buffer} starting at {@code
* offset}. Blocks until {@code count} bytes have been read, the end of the
* file is reached or an exception is thrown.
*
* @param buffer
* the array in which to store the bytes read from this file.
* @param offset
* the initial position in {@code buffer} to store the bytes read
* from this file.
* @param count
* the maximum number of bytes to store in {@code buffer}.
* @return the number of bytes actually read or -1 if the end of the stream
* has been reached.
* @throws IndexOutOfBoundsException
* if {@code offset < 0} or {@code count < 0}, or if {@code
* offset + count} is greater than the size of {@code buffer}.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @since Android 1.0
*/
public int read(byte[] buffer, int offset, int count) throws IOException {
// have to have four comparisions to not miss integer overflow cases
// BEGIN android-changed
// Exception priorities (in case of multiple errors) differ from
// RI, but are spec-compliant.
// made implicit null check explicit, used (offset | count) < 0
// instead of (offset < 0) || (count < 0) to safe one operation
if (buffer == null) {
throw new NullPointerException(Msg.getString("K0047")); //$NON-NLS-1$
}
if ((offset | count) < 0 || count > buffer.length - offset) {
throw new IndexOutOfBoundsException(Msg.getString("K002f")); //$NON-NLS-1$
}
// END android-changed
if (0 == count) {
return 0;
}
openCheck();
synchronized (repositionLock) {
return (int) fileSystem.read(fd.descriptor, buffer, offset, count);
}
}
/**
* Reads a boolean from the current position in this file. Blocks until one
* byte has been read, the end of the file is reached or an exception is
* thrown.
*
* @return the next boolean value from this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeBoolean(boolean)
* @since Android 1.0
*/
public final boolean readBoolean() throws IOException {
int temp = this.read();
if (temp < 0) {
throw new EOFException();
}
return temp != 0;
}
/**
* Reads an 8-bit byte from the current position in this file. Blocks until
* one byte has been read, the end of the file is reached or an exception is
* thrown.
*
* @return the next signed 8-bit byte value from this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeBoolean(boolean)
* @since Android 1.0
*/
public final byte readByte() throws IOException {
int temp = this.read();
if (temp < 0) {
throw new EOFException();
}
return (byte) temp;
}
/**
* Reads a 16-bit character from the current position in this file. Blocks until
* two bytes have been read, the end of the file is reached or an exception is
* thrown.
*
* @return the next char value from this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeChar(int)
* @since Android 1.0
*/
public final char readChar() throws IOException {
byte[] buffer = new byte[2];
if (read(buffer, 0, buffer.length) != buffer.length) {
throw new EOFException();
}
return (char) (((buffer[0] & 0xff) << 8) + (buffer[1] & 0xff));
}
/**
* Reads a 64-bit double from the current position in this file. Blocks
* until eight bytes have been read, the end of the file is reached or an
* exception is thrown.
*
* @return the next double value from this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeDouble(double)
* @since Android 1.0
*/
public final double readDouble() throws IOException {
return Double.longBitsToDouble(readLong());
}
/**
* Reads a 32-bit float from the current position in this file. Blocks
* until four bytes have been read, the end of the file is reached or an
* exception is thrown.
*
* @return the next float value from this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeFloat(float)
* @since Android 1.0
*/
public final float readFloat() throws IOException {
return Float.intBitsToFloat(readInt());
}
/**
* Reads bytes from this file into {@code buffer}. Blocks until {@code
* buffer.length} number of bytes have been read, the end of the file is
* reached or an exception is thrown.
*
* @param buffer
* the buffer to read bytes into.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @throws NullPointerException
* if {@code buffer} is {@code null}.
* @since Android 1.0
*/
public final void readFully(byte[] buffer) throws IOException {
readFully(buffer, 0, buffer.length);
}
/**
* Read bytes from this file into {@code buffer} starting at offset {@code
* offset}. This method blocks until {@code count} number of bytes have been
* read.
*
* @param buffer
* the buffer to read bytes into.
* @param offset
* the initial position in {@code buffer} to store the bytes read
* from this file.
* @param count
* the maximum number of bytes to store in {@code buffer}.
* @throws EOFException
* if the end of this file is detected.
* @throws IndexOutOfBoundsException
* if {@code offset < 0} or {@code count < 0}, or if {@code
* offset + count} is greater than the length of {@code buffer}.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @throws NullPointerException
* if {@code buffer} is {@code null}.
* @since Android 1.0
*/
public final void readFully(byte[] buffer, int offset, int count)
throws IOException {
if (buffer == null) {
throw new NullPointerException(Msg.getString("K0047")); //$NON-NLS-1$
}
// avoid int overflow
// BEGIN android-changed
// Exception priorities (in case of multiple errors) differ from
// RI, but are spec-compliant.
// removed redundant check, used (offset | count) < 0
// instead of (offset < 0) || (count < 0) to safe one operation
if ((offset | count) < 0 || count > buffer.length - offset) {
throw new IndexOutOfBoundsException(Msg.getString("K002f")); //$NON-NLS-1$
}
// END android-changed
while (count > 0) {
int result = read(buffer, offset, count);
if (result < 0) {
throw new EOFException();
}
offset += result;
count -= result;
}
}
/**
* Reads a 32-bit integer from the current position in this file. Blocks
* until four bytes have been read, the end of the file is reached or an
* exception is thrown.
*
* @return the next int value from this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeInt(int)
* @since Android 1.0
*/
public final int readInt() throws IOException {
byte[] buffer = new byte[4];
if (read(buffer, 0, buffer.length) != buffer.length) {
throw new EOFException();
}
return ((buffer[0] & 0xff) << 24) + ((buffer[1] & 0xff) << 16)
+ ((buffer[2] & 0xff) << 8) + (buffer[3] & 0xff);
}
/**
* Reads a line of text form the current position in this file. A line is
* represented by zero or more characters followed by {@code '\n'}, {@code
* '\r'}, {@code "\r\n"} or the end of file marker. The string does not
* include the line terminating sequence.
* <p>
* Blocks until a line terminating sequence has been read, the end of the
* file is reached or an exception is thrown.
* </p>
*
* @return the contents of the line or {@code null} if no characters have
* been read before the end of the file has been reached.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @since Android 1.0
*/
public final String readLine() throws IOException {
StringBuilder line = new StringBuilder(80); // Typical line length
boolean foundTerminator = false;
long unreadPosition = 0;
while (true) {
int nextByte = read();
switch (nextByte) {
case -1:
return line.length() != 0 ? line.toString() : null;
case (byte) '\r':
if (foundTerminator) {
seek(unreadPosition);
return line.toString();
}
foundTerminator = true;
/* Have to be able to peek ahead one byte */
unreadPosition = getFilePointer();
break;
case (byte) '\n':
return line.toString();
default:
if (foundTerminator) {
seek(unreadPosition);
return line.toString();
}
line.append((char) nextByte);
}
}
}
/**
* Reads a 64-bit long from the current position in this file. Blocks until
* eight bytes have been read, the end of the file is reached or an
* exception is thrown.
*
* @return the next long value from this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeLong(long)
* @since Android 1.0
*/
public final long readLong() throws IOException {
byte[] buffer = new byte[8];
if (read(buffer, 0, buffer.length) != buffer.length) {
throw new EOFException();
}
return ((long) (((buffer[0] & 0xff) << 24) + ((buffer[1] & 0xff) << 16)
+ ((buffer[2] & 0xff) << 8) + (buffer[3] & 0xff)) << 32)
+ ((long) (buffer[4] & 0xff) << 24)
+ ((buffer[5] & 0xff) << 16)
+ ((buffer[6] & 0xff) << 8)
+ (buffer[7] & 0xff);
}
/**
* Reads a 16-bit short from the current position in this file. Blocks until
* two bytes have been read, the end of the file is reached or an exception
* is thrown.
*
* @return the next short value from this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeShort(int)
* @since Android 1.0
*/
public final short readShort() throws IOException {
byte[] buffer = new byte[2];
if (read(buffer, 0, buffer.length) != buffer.length) {
throw new EOFException();
}
return (short) (((buffer[0] & 0xff) << 8) + (buffer[1] & 0xff));
}
/**
* Reads an unsigned 8-bit byte from the current position in this file and
* returns it as an integer. Blocks until one byte has been read, the end of
* the file is reached or an exception is thrown.
*
* @return the next unsigned byte value from this file as an int.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeByte(int)
* @since Android 1.0
*/
public final int readUnsignedByte() throws IOException {
int temp = this.read();
if (temp < 0) {
throw new EOFException();
}
return temp;
}
/**
* Reads an unsigned 16-bit short from the current position in this file and
* returns it as an integer. Blocks until two bytes have been read, the end of
* the file is reached or an exception is thrown.
*
* @return the next unsigned short value from this file as an int.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #writeShort(int)
* @since Android 1.0
*/
public final int readUnsignedShort() throws IOException {
byte[] buffer = new byte[2];
if (read(buffer, 0, buffer.length) != buffer.length) {
throw new EOFException();
}
return ((buffer[0] & 0xff) << 8) + (buffer[1] & 0xff);
}
/**
* Reads a string that is encoded in {@link DataInput modified UTF-8} from
* this file. The number of bytes that must be read for the complete string
* is determined by the first two bytes read from the file. Blocks until all
* required bytes have been read, the end of the file is reached or an
* exception is thrown.
*
* @return the next string encoded in {@link DataInput modified UTF-8} from
* this file.
* @throws EOFException
* if the end of this file is detected.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @throws UTFDataFormatException
* if the bytes read cannot be decoded into a character string.
* @see #writeUTF(String)
* @since Android 1.0
*/
public final String readUTF() throws IOException {
int utfSize = readUnsignedShort();
if (utfSize == 0) {
return ""; //$NON-NLS-1$
}
byte[] buf = new byte[utfSize];
if (read(buf, 0, buf.length) != buf.length) {
throw new EOFException();
}
return Util.convertFromUTF8(buf, 0, utfSize);
}
/**
* Moves this file's file pointer to a new position, from where following
* {@code read}, {@code write} or {@code skip} operations are done. The
* position may be greater than the current length of the file, but the
* file's length will only change if the moving of the pointer is followed
* by a {@code write} operation.
*
* @param pos
* the new file pointer position.
* @throws IOException
* if this file is closed, {@code pos < 0} or another I/O error
* occurs.
* @since Android 1.0
*/
public void seek(long pos) throws IOException {
if (pos < 0) {
// seek position is negative
throw new IOException(Msg.getString("K0347")); //$NON-NLS-1$
}
openCheck();
synchronized (repositionLock) {
fileSystem.seek(fd.descriptor, pos, IFileSystem.SEEK_SET);
}
}
/**
* Sets the length of this file to {@code newLength}. If the current file is
* smaller, it is expanded but the contents from the previous end of the
* file to the new end are undefined. The file is truncated if its current
* size is bigger than {@code newLength}. If the current file pointer
* position is in the truncated part, it is set to the end of the file.
*
* @param newLength
* the new file length in bytes.
* @throws IllegalArgumentException
* if {@code newLength < 0}.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @since Android 1.0
*/
public void setLength(long newLength) throws IOException {
openCheck();
if (newLength < 0) {
throw new IllegalArgumentException();
}
synchronized (repositionLock) {
long position = fileSystem.seek(fd.descriptor, 0,
IFileSystem.SEEK_CUR);
fileSystem.truncate(fd.descriptor, newLength);
seek(position > newLength ? newLength : position);
}
// if we are in "rws" mode, attempt to sync file+metadata
if (syncMetadata) {
fd.sync();
}
}
/**
* Skips over {@code count} bytes in this file. Less than {@code count}
* bytes are skipped if the end of the file is reached or an exception is
* thrown during the operation. Nothing is done if {@code count} is
* negative.
*
* @param count
* the number of bytes to skip.
* @return the number of bytes actually skipped.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @since Android 1.0
*/
public int skipBytes(int count) throws IOException {
if (count > 0) {
long currentPos = getFilePointer(), eof = length();
int newCount = (int) ((currentPos + count > eof) ? eof - currentPos
: count);
seek(currentPos + newCount);
return newCount;
}
return 0;
}
/**
* Writes the entire contents of the byte array {@code buffer} to this file,
* starting at the current file pointer.
*
* @param buffer
* the buffer to write.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #read(byte[])
* @see #read(byte[],int,int)
* @see #readFully(byte[])
* @see #readFully(byte[],int,int)
* @since Android 1.0
*/
public void write(byte[] buffer) throws IOException {
write(buffer, 0, buffer.length);
}
/**
* Writes {@code count} bytes from the byte array {@code buffer} to this
* file, starting at the current file pointer and using {@code offset} as
* the first position within {@code buffer} to get bytes.
*
* @param buffer
* the buffer to write to this file.
* @param offset
* the index of the first byte in {@code buffer} to write.
* @param count
* the number of bytes from {@code buffer} to write.
* @throws IndexOutOfBoundsException
* if {@code count < 0}, {@code offset < 0} or {@code count +
* offset} is greater than the size of {@code buffer}.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #read(byte[], int, int)
* @see #readFully(byte[], int, int)
* @since Android 1.0
*/
public void write(byte[] buffer, int offset, int count) throws IOException {
// BEGIN android-changed
// Exception priorities (in case of multiple errors) differ from
// RI, but are spec-compliant.
// made implicit null check explicit,
// removed redundant check, used (offset | count) < 0
// instead of (offset < 0) || (count < 0) to safe one operation
if (buffer == null) {
throw new NullPointerException(Msg.getString("K0047")); //$NON-NLS-1$
}
if ((offset | count) < 0 || count > buffer.length - offset) {
throw new IndexOutOfBoundsException(Msg.getString("K002f")); //$NON-NLS-1$
}
// END android-changed
if (count == 0) {
return;
}
// BEGIN android-added
openCheck();
// END android-added
synchronized (repositionLock) {
fileSystem.write(fd.descriptor, buffer, offset, count);
}
// if we are in "rws" mode, attempt to sync file+metadata
if (syncMetadata) {
fd.sync();
}
}
/**
* Writes a byte to this file, starting at the current file pointer. Only
* the least significant byte of the integer {@code oneByte} is written.
*
* @param oneByte
* the byte to write to this file.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #read()
* @since Android 1.0
*/
public void write(int oneByte) throws IOException {
openCheck();
byte[] bytes = new byte[1];
bytes[0] = (byte) (oneByte & 0xff);
synchronized (repositionLock) {
fileSystem.write(fd.descriptor, bytes, 0, 1);
}
// if we are in "rws" mode, attempt to sync file+metadata
if (syncMetadata) {
fd.sync();
}
}
/**
* Writes a boolean to this file, starting at the current file pointer.
*
* @param val
* the boolean to write to this file.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #readBoolean()
* @since Android 1.0
*/
public final void writeBoolean(boolean val) throws IOException {
write(val ? 1 : 0);
}
/**
* Writes an 8-bit byte to this file, starting at the current file pointer.
* Only the least significant byte of the integer {@code val} is written.
*
* @param val
* the byte to write to this file.
* @throws IOException
* if this file is closed or another I/O error occurs.
* @see #readByte()
* @see #readUnsignedByte()
* @since Android 1.0
*/
public final void writeByte(int val) throws IOException {
write(val & 0xFF);
}
/**
* Writes the low order 8-bit bytes from a string to this file, starting at
* the current file pointer.
*
* @param str
* the string containing the bytes to write to this file
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #read(byte[])
* @see #read(byte[],int,int)
* @see #readFully(byte[])
* @see #readFully(byte[],int,int)
* @since Android 1.0
*/
public final void writeBytes(String str) throws IOException {
byte bytes[] = new byte[str.length()];
for (int index = 0; index < str.length(); index++) {
bytes[index] = (byte) (str.charAt(index) & 0xFF);
}
write(bytes);
}
/**
* Writes a 16-bit character to this file, starting at the current file
* pointer. Only the two least significant bytes of the integer {@code val}
* are written, with the high byte first.
*
* @param val
* the char to write to this file.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #readChar()
* @since Android 1.0
*/
public final void writeChar(int val) throws IOException {
byte[] buffer = new byte[2];
buffer[0] = (byte) (val >> 8);
buffer[1] = (byte) val;
write(buffer, 0, buffer.length);
}
/**
* Writes the 16-bit characters from a string to this file, starting at the
* current file pointer. Each character is written in the same way as with
* {@link #writeChar(int)}, with its high byte first.
*
* @param str
* the string to write to this file.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #readChar()
* @since Android 1.0
*/
public final void writeChars(String str) throws IOException {
byte newBytes[] = new byte[str.length() * 2];
for (int index = 0; index < str.length(); index++) {
int newIndex = index == 0 ? index : index * 2;
newBytes[newIndex] = (byte) ((str.charAt(index) >> 8) & 0xFF);
newBytes[newIndex + 1] = (byte) (str.charAt(index) & 0xFF);
}
write(newBytes);
}
/**
* Writes a 64-bit double to this file, starting at the current file
* pointer. The eight bytes returned by
* {@link Double#doubleToLongBits(double)} are written to this file.
*
* @param val
* the double to write to this file.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #readDouble()
* @since Android 1.0
*/
public final void writeDouble(double val) throws IOException {
writeLong(Double.doubleToLongBits(val));
}
/**
* Writes a 32-bit float to this file, starting at the current file pointer.
* The four bytes returned by {@link Float#floatToIntBits(float)} are
* written to this file.
*
* @param val
* the float to write to this file.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #readFloat()
* @since Android 1.0
*/
public final void writeFloat(float val) throws IOException {
writeInt(Float.floatToIntBits(val));
}
/**
* Writes a 32-bit integer to this file, starting at the current file
* pointer. The four bytes of the integer are written with the highest byte
* first.
*
* @param val
* the int to write to this file.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #readInt()
* @since Android 1.0
*/
public final void writeInt(int val) throws IOException {
byte[] buffer = new byte[4];
buffer[0] = (byte) (val >> 24);
buffer[1] = (byte) (val >> 16);
buffer[2] = (byte) (val >> 8);
buffer[3] = (byte) val;
write(buffer, 0, buffer.length);
}
/**
* Writes a 64-bit long to this file, starting at the current file
* pointer. The eight bytes of the long are written with the highest byte
* first.
*
* @param val
* the long to write to this file.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #readLong()
* @since Android 1.0
*/
public final void writeLong(long val) throws IOException {
byte[] buffer = new byte[8];
int t = (int) (val >> 32);
buffer[0] = (byte) (t >> 24);
buffer[1] = (byte) (t >> 16);
buffer[2] = (byte) (t >> 8);
buffer[3] = (byte) t;
buffer[4] = (byte) (val >> 24);
buffer[5] = (byte) (val >> 16);
buffer[6] = (byte) (val >> 8);
buffer[7] = (byte) val;
write(buffer, 0, buffer.length);
}
/**
* Writes a 16-bit short to this file, starting at the current file
* pointer. Only the two least significant bytes of the integer {@code val}
* are written, with the high byte first.
*
* @param val
* the short to write to this file.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @see #readShort()
* @since Android 1.0
*/
public final void writeShort(int val) throws IOException {
writeChar(val);
}
/**
* Writes a string encoded with {@link DataInput modified UTF-8} to this
* file, starting at the current file pointer.
*
* @param str
* the string to write in {@link DataInput modified UTF-8}
* format.
* @throws IOException
* if an I/O error occurs while writing to this file.
* @throws UTFDataFormatException
* if the encoded string is longer than 65535 bytes.
* @see #readUTF()
* @since Android 1.0
*/
public final void writeUTF(String str) throws IOException {
int utfCount = 0, length = str.length();
for (int i = 0; i < length; i++) {
int charValue = str.charAt(i);
if (charValue > 0 && charValue <= 127) {
utfCount++;
} else if (charValue <= 2047) {
utfCount += 2;
} else {
utfCount += 3;
}
}
if (utfCount > 65535) {
throw new UTFDataFormatException(Msg.getString("K0068")); //$NON-NLS-1$
}
byte utfBytes[] = new byte[utfCount + 2];
int utfIndex = 2;
for (int i = 0; i < length; i++) {
int charValue = str.charAt(i);
if (charValue > 0 && charValue <= 127) {
utfBytes[utfIndex++] = (byte) charValue;
} else if (charValue <= 2047) {
utfBytes[utfIndex++] = (byte) (0xc0 | (0x1f & (charValue >> 6)));
utfBytes[utfIndex++] = (byte) (0x80 | (0x3f & charValue));
} else {
utfBytes[utfIndex++] = (byte) (0xe0 | (0x0f & (charValue >> 12)));
utfBytes[utfIndex++] = (byte) (0x80 | (0x3f & (charValue >> 6)));
utfBytes[utfIndex++] = (byte) (0x80 | (0x3f & charValue));
}
}
utfBytes[0] = (byte) (utfCount >> 8);
utfBytes[1] = (byte) utfCount;
write(utfBytes);
}
}
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