Package org.postgresql.jdbc

Class AbstractBlobClob

java.lang.Object

org.postgresql.jdbc.AbstractBlobClob

Direct Known Subclasses:

PgBlob, PgClob

public abstract class AbstractBlobClob
extends java.lang.Object

This class holds all of the methods common to both Blobs and Clobs.

Author:

Michael Barker

Field Summary

Fields

Modifier and Type	Field	Description
protected BaseConnection	conn
protected ResourceLock	lock

Constructor Summary

Constructors

Constructor	Description
AbstractBlobClob(BaseConnection conn, long oid)

Method Summary

Modifier and Type	Method	Description
protected void	addSubLO(LargeObject subLO)
protected void	assertPosition(long pos)	Throws an exception if the pos value exceeds the max value by which the large object API can index.
protected void	assertPosition(long pos, long len)	Throws an exception if the pos value exceeds the max value by which the large object API can index.
protected void	checkFreed()	Checks that this LOB hasn't been free()d already.
void	free()
java.io.InputStream	getBinaryStream()
byte[]	getBytes(long pos, int length)
protected LargeObject	getLo(boolean forWrite)
long	length()
long	position(byte[] pattern, long start)	Iterate over the buffer looking for the specified pattern.
long	position(java.sql.Blob pattern, long start)	This is simply passing the byte value of the pattern Blob.
java.io.OutputStream	setBinaryStream(long pos)
void	truncate(long len)	For Blobs this should be in bytes while for Clobs it should be in characters.

Methods inherited from class java.lang.Object

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

Field Detail

conn

protected BaseConnection conn

lock

protected final ResourceLock lock

Constructor Detail

AbstractBlobClob

public AbstractBlobClob(BaseConnection conn,
                        long oid)
                 throws java.sql.SQLException

Throws:

java.sql.SQLException

Method Detail

free

public void free()
          throws java.sql.SQLException

Throws:

java.sql.SQLException

truncate

public void truncate(long len)
              throws java.sql.SQLException

For Blobs this should be in bytes while for Clobs it should be in characters. Since we really haven't figured out how to handle character sets for Clobs the current implementation uses bytes for both Blobs and Clobs.

Parameters:

len - maximum length

Throws:

java.sql.SQLException - if operation fails

length

public long length()
            throws java.sql.SQLException

Throws:

java.sql.SQLException

getBytes

public byte[] getBytes(long pos,
                       int length)
                throws java.sql.SQLException

Throws:

java.sql.SQLException

getBinaryStream

public java.io.InputStream getBinaryStream()
                                    throws java.sql.SQLException

Throws:

java.sql.SQLException

setBinaryStream

public java.io.OutputStream setBinaryStream(long pos)
                                     throws java.sql.SQLException

Throws:

java.sql.SQLException

position

public long position(byte[] pattern,
                     long start)
              throws java.sql.SQLException

Iterate over the buffer looking for the specified pattern.

Parameters:

pattern - A pattern of bytes to search the blob for

start - The position to start reading from

Returns:

position of the specified pattern

Throws:

java.sql.SQLException - if something wrong happens

position

public long position(java.sql.Blob pattern,
                     long start)
              throws java.sql.SQLException

This is simply passing the byte value of the pattern Blob.

Parameters:

pattern - search pattern

start - start position

Returns:

position of given pattern

Throws:

java.sql.SQLException - if something goes wrong

assertPosition

protected void assertPosition(long pos)
                       throws java.sql.SQLException

Throws an exception if the pos value exceeds the max value by which the large object API can index.

Parameters:

pos - Position to write at.

Throws:

java.sql.SQLException - if something goes wrong

assertPosition

protected void assertPosition(long pos,
                              long len)
                       throws java.sql.SQLException

Throws an exception if the pos value exceeds the max value by which the large object API can index.

Parameters:

pos - Position to write at.

len - number of bytes to write.

Throws:

java.sql.SQLException - if something goes wrong

checkFreed

protected void checkFreed()
                   throws java.sql.SQLException

Checks that this LOB hasn't been free()d already.

Throws:

java.sql.SQLException - if LOB has been freed.

getLo

protected LargeObject getLo(boolean forWrite)
                     throws java.sql.SQLException

Throws:

java.sql.SQLException

addSubLO

protected void addSubLO(LargeObject subLO)