Package org.apache.bookkeeper.bookie.storage.directentrylogger

Interface LogReader

All Superinterfaces:

java.lang.AutoCloseable

All Known Implementing Classes:

DirectReader

public interface LogReader
extends java.lang.AutoCloseable

Interface for reading from a bookkeeper entry log.

Method Summary

Modifier and Type	Method	Description
void	close()
boolean	isClosed()
int	logId()
long	maxOffset()
io.netty.buffer.ByteBuf	readBufferAt(long offset, int size)	Read a buffer from the file.
io.netty.buffer.ByteBuf	readEntryAt(int offset)	Read an entry at a given offset.
int	readIntAt(long offset)	Read an integer at a given offset.
void	readIntoBufferAt(io.netty.buffer.ByteBuf buffer, long offset, int size)
long	readLongAt(long offset)	Read an long at a given offset.

Method Detail

logId

int logId()

Returns:

the id of the log being read from.

maxOffset

long maxOffset()

Returns:

the maximum offset in the file that can be read from.

readBufferAt

io.netty.buffer.ByteBuf readBufferAt(long offset,
                                     int size)
                              throws java.io.IOException,
                                     java.io.EOFException

Read a buffer from the file. It is the responsibility of the caller to release the returned buffer.

Parameters:

offset - the offset to read at

size - the number of bytes to read

Returns:

a bytebuf. The caller must release.

Throws:

java.io.IOException

java.io.EOFException

readIntoBufferAt

void readIntoBufferAt(io.netty.buffer.ByteBuf buffer,
                      long offset,
                      int size)
               throws java.io.IOException,
                      java.io.EOFException

Throws:

java.io.IOException

java.io.EOFException

readIntAt

int readIntAt(long offset)
       throws java.io.IOException,
              java.io.EOFException

Read an integer at a given offset.

Parameters:

offset - the offset to read from.

Returns:

the integer at that offset.

Throws:

java.io.IOException

java.io.EOFException

readLongAt

long readLongAt(long offset)
         throws java.io.IOException,
                java.io.EOFException

Read an long at a given offset.

Parameters:

offset - the offset to read from.

Returns:

the long at that offset.

Throws:

java.io.IOException

java.io.EOFException

readEntryAt

io.netty.buffer.ByteBuf readEntryAt(int offset)
                             throws java.io.IOException,
                                    java.io.EOFException

Read an entry at a given offset. The size of the entry must be at (offset - Integer.BYTES). The payload of the entry starts at offset. It is the responsibility of the caller to release the returned buffer.

Parameters:

offset - the offset at which to read the entry.

Returns:

a bytebuf. The caller must release.

Throws:

java.io.IOException

java.io.EOFException

close

void close()
    throws java.io.IOException

Specified by:

close in interface java.lang.AutoCloseable

Throws:

java.io.IOException

isClosed

boolean isClosed()