com.caucho.vfs

Class DatastoreRandomAccessStream

java.lang.Object

com.caucho.vfs.RandomAccessStream

com.caucho.vfs.DatastoreRandomAccessStream

All Implemented Interfaces:

LockableStream

public class DatastoreRandomAccessStream
extends RandomAccessStream
implements LockableStream

Reads from a file in a random-access fashion.

Constructor Summary

Constructors

Constructor and Description
DatastoreRandomAccessStream(DatastoreRandomAccessFile file)

Method Summary

Modifier and Type	Method and Description
void	closeImpl() Closes the stream.
long	getFilePointer() Returns the current position of the file pointer.
java.io.InputStream	getInputStream() Returns an InputStream for this stream.
long	getLength() Returns the length.
java.io.OutputStream	getOutputStream() Returns an OutputStream for this stream.
DatastoreRandomAccessFile	getRandomAccessFile()
boolean	lock(boolean shared, boolean block) Lock the shared advisory lock.
int	read() Read a byte from the file, advancing the pointer.
int	read(byte[] buffer, int offset, int length) Reads a block starting from the current file pointer.
int	read(char[] buffer, int offset, int length) Reads a block starting from the current file pointer.
int	read(long fileOffset, byte[] buffer, int offset, int length) Reads a block from a given location.
boolean	seek(long position) Seeks to the given position in the file.
boolean	unlock() Unlock the advisory lock.
void	write(byte[] buffer, int offset, int length) Writes a block starting from the current file pointer.
void	write(int b) Write a byte to the file, advancing the pointer.
void	write(long fileOffset, byte[] buffer, int offset, int length) Writes a block from a given location.

Methods inherited from class com.caucho.vfs.RandomAccessStream

allocate, close, free, fsync, getMmapAddress, getUseCount, isMmap, isOpen, writeToStream

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Constructor Detail

DatastoreRandomAccessStream

public DatastoreRandomAccessStream(DatastoreRandomAccessFile file)

Method Detail

getRandomAccessFile

public DatastoreRandomAccessFile getRandomAccessFile()

getLength

public long getLength()
               throws java.io.IOException

Returns the length.

Specified by:

getLength in class RandomAccessStream

Throws:

java.io.IOException

read

public int read(byte[] buffer,
                int offset,
                int length)
         throws java.io.IOException

Reads a block starting from the current file pointer.

Specified by:

read in class RandomAccessStream

Throws:

java.io.IOException

read

public int read(char[] buffer,
                int offset,
                int length)
         throws java.io.IOException

Reads a block starting from the current file pointer.

Specified by:

read in class RandomAccessStream

Throws:

java.io.IOException

read

public int read(long fileOffset,
                byte[] buffer,
                int offset,
                int length)
         throws java.io.IOException

Reads a block from a given location.

Specified by:

read in class RandomAccessStream

Throws:

java.io.IOException

write

public void write(byte[] buffer,
                  int offset,
                  int length)
           throws java.io.IOException

Writes a block starting from the current file pointer.

Specified by:

write in class RandomAccessStream

Throws:

java.io.IOException

write

public void write(long fileOffset,
                  byte[] buffer,
                  int offset,
                  int length)
           throws java.io.IOException

Writes a block from a given location.

Specified by:

write in class RandomAccessStream

Throws:

java.io.IOException

seek

public boolean seek(long position)

Seeks to the given position in the file.

Specified by:

seek in class RandomAccessStream

getOutputStream

public java.io.OutputStream getOutputStream()
                                     throws java.io.IOException

Returns an OutputStream for this stream.

Specified by:

getOutputStream in class RandomAccessStream

Throws:

java.io.IOException

getInputStream

public java.io.InputStream getInputStream()
                                   throws java.io.IOException

Returns an InputStream for this stream.

Specified by:

getInputStream in class RandomAccessStream

Throws:

java.io.IOException

read

public int read()
         throws java.io.IOException

Read a byte from the file, advancing the pointer.

Specified by:

read in class RandomAccessStream

Throws:

java.io.IOException

write

public void write(int b)
           throws java.io.IOException

Write a byte to the file, advancing the pointer.

Specified by:

write in class RandomAccessStream

Throws:

java.io.IOException

getFilePointer

public long getFilePointer()
                    throws java.io.IOException

Returns the current position of the file pointer.

Specified by:

getFilePointer in class RandomAccessStream

Throws:

java.io.IOException

closeImpl

public void closeImpl()
               throws java.io.IOException

Closes the stream.

Overrides:

closeImpl in class RandomAccessStream

Throws:

java.io.IOException

lock

public boolean lock(boolean shared,
                    boolean block)

Description copied from interface: LockableStream

Lock the shared advisory lock. This method will create a shared "read" lock when the shared argument is true and an exclusive "write" lock when the shared argument is false. If the block argument is false then this call will not block if the lock can't be obtained.

Specified by:

lock in interface LockableStream

Overrides:

lock in class RandomAccessStream

unlock

public boolean unlock()

Description copied from interface: LockableStream

Unlock the advisory lock. Return true if a lock was held, false otherwise.

Specified by:

unlock in interface LockableStream

Overrides:

unlock in class RandomAccessStream