File	Doc	Category	Size	Date	Package
FileLock.java	API Doc	Android 1.5 API	8177	Wed May 06 22:41:04 BST 2009	java.nio.channels

FileLock

• java.lang.Object

Fields Summary
private final FileChannel	channel
private final long	position
private final long	size
private final boolean	shared

Constructors Summary

protected FileLock(FileChannel channel, long position, long size, boolean shared) Constructs a new file lock instance for a given channel. The constructor enforces the starting position, length and sharing mode of the lock. param channel the underlying file channel that holds the lock. param position the starting point for the lock. param size the length of the lock in number of bytes. param shared the lock's sharing mode of lock; {@code true} is shared, {@code false} is exclusive. since Android 1.0 super(); if (position < 0 || size < 0 || position + size < 0) { throw new IllegalArgumentException(); } this.channel = channel; this.position = position; this.size = size; this.shared = shared;

Methods Summary
public final java.nio.channels.FileChannel	channel() Returns the lock's {@link FileChannel}. return the channel. since Android 1.0 return channel;
public final boolean	isShared() Indicates if the file lock is shared with other processes or if it is exclusive. return {@code true} if the lock is a shared lock, {@code false} if it is exclusive. since Android 1.0 return shared;
public abstract boolean	isValid() Indicates whether this lock is a valid file lock. The lock is valid unless the underlying channel has been closed or it has been explicitly released. return {@code true} if the lock is valid, {@code false} otherwise. since Android 1.0
public final boolean	overlaps(long start, long length) Indicates if the receiver's lock region overlaps the region described in the parameter list. param start the starting position for the comparative lock. param length the length of the comparative lock. return {@code true} if there is an overlap, {@code false} otherwise. since Android 1.0 final long end = position + size - 1; final long newEnd = start + length - 1; if (end < start || position > newEnd) { return false; } return true;
public final long	position() Returns the lock's starting position in the file. return the lock position. since Android 1.0 return position;
public abstract void	release() Releases this particular lock on the file. If the lock is invalid then this method has no effect. Once released, the lock becomes invalid. throws ClosedChannelException if the channel is already closed when an attempt to release the lock is made. throws IOException if another I/O error occurs. since Android 1.0
public final long	size() Returns the length of the file lock in bytes. return the size of the file lock in bytes. since Android 1.0 return size;
public final java.lang.String	toString() Returns a string that shows the details of the lock suitable for display to an end user. return the display string. since Android 1.0 StringBuffer buffer = new StringBuffer(64); // Guess length of string buffer.append("FileLock: [position="); //$NON-NLS-1$ buffer.append(position); buffer.append(", size="); //$NON-NLS-1$ buffer.append(size); buffer.append(", shared="); //$NON-NLS-1$ buffer.append(Boolean.toString(shared)); buffer.append("]"); //$NON-NLS-1$ return buffer.toString();