org.hsqldb.jdbc
Class JDBCBlobClient

java.lang.Object
  org.hsqldb.jdbc.JDBCBlobClient

All Implemented Interfaces:

Blob

public class JDBCBlobClient
extends Object
implements Blob

A wrapper for HSQLDB BlobData objects. Instances of this class are returnd by calls to ResultSet methods.

Since:

1.9.0

Author:

Fred Toussi (fredt@users dot sourceforge.net)

Constructor Summary

JDBCBlobClient(org.hsqldb.SessionInterface session, org.hsqldb.types.BlobDataID blob)

Method Summary

void	clearUpdates()
void	free() This method frees the Blob object and releases the resources that it holds.
InputStream	getBinaryStream() Retrieves the BLOB value designated by this Blob instance as a stream.
InputStream	getBinaryStream(long pos, long length) Returns an InputStream object that contains a partial Blob value, starting with the byte specified by pos, which is length bytes in length.
org.hsqldb.types.BlobDataID	getBlob()
byte[]	getBytes(long pos, int length) Retrieves all or part of the BLOB value that this Blob object represents, as an array of bytes.
boolean	isClosed()
long	length() Returns the number of bytes in the BLOB value designated by this Blob object.
long	position(Blob pattern, long start) Retrieves the byte position in the BLOB value designated by this Blob object at which pattern begins.
long	position(byte[] pattern, long start) Retrieves the byte position at which the specified byte array pattern begins within the BLOB value that this Blob object represents.
OutputStream	setBinaryStream(long pos) Retrieves a stream that can be used to write to the BLOB value that this Blob object represents.
int	setBytes(long pos, byte[] bytes) Writes the given array of bytes to the BLOB value that this Blob object represents, starting at position pos, and returns the number of bytes written.
int	setBytes(long pos, byte[] bytes, int offset, int len) Writes all or part of the given byte array to the BLOB value that this Blob object represents and returns the number of bytes written.
void	setWritable(JDBCResultSet result, int index)
void	truncate(long len) Truncates the BLOB value that this Blob object represents to be len bytes in length.

Methods inherited from class java.lang.Object

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

Constructor Detail

JDBCBlobClient

public JDBCBlobClient(org.hsqldb.SessionInterface session,
                      org.hsqldb.types.BlobDataID blob)

Method Detail

length

public long length()
            throws SQLException

Returns the number of bytes in the BLOB value designated by this Blob object.

Specified by:

length in interface Blob

Returns:

length of the BLOB in bytes

Throws:

SQLException - if there is an error accessing the length of the BLOB

getBytes

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

Retrieves all or part of the BLOB value that this Blob object represents, as an array of bytes.

Specified by:

getBytes in interface Blob

Parameters:

pos - the ordinal position of the first byte in the BLOB value to be extracted; the first byte is at position 1

length - the number of consecutive bytes to be copied

Returns:

a byte array containing up to length consecutive bytes from the BLOB value designated by this Blob object, starting with the byte at position pos

Throws:

SQLException - if there is an error accessing the BLOB value

getBinaryStream

public InputStream getBinaryStream()
                            throws SQLException

Retrieves the BLOB value designated by this Blob instance as a stream.

Specified by:

getBinaryStream in interface Blob

Returns:

a stream containing the BLOB data

Throws:

SQLException - if there is an error accessing the BLOB value

position

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

Retrieves the byte position at which the specified byte array pattern begins within the BLOB value that this Blob object represents.

Specified by:

position in interface Blob

Parameters:

pattern - the byte array for which to search

start - the position at which to begin searching; the first position is 1

Returns:

the position at which the pattern appears, else -1

Throws:

SQLException - if there is an error accessing the BLOB

position

public long position(Blob pattern,
                     long start)
              throws SQLException

Retrieves the byte position in the BLOB value designated by this Blob object at which pattern begins.

Specified by:

position in interface Blob

Parameters:

pattern - the Blob object designating the BLOB value for which to search

start - the position in the BLOB value at which to begin searching; the first position is 1

Returns:

the position at which the pattern begins, else -1

Throws:

SQLException - if there is an error accessing the BLOB value

setBytes

public int setBytes(long pos,
                    byte[] bytes)
             throws SQLException

Writes the given array of bytes to the BLOB value that this Blob object represents, starting at position pos, and returns the number of bytes written.

Specified by:

setBytes in interface Blob

Parameters:

pos - the position in the BLOB object at which to start writing

bytes - the array of bytes to be written to the BLOB value that this Blob object represents

Returns:

the number of bytes written

Throws:

SQLException - if there is an error accessing the BLOB value

setBytes

public int setBytes(long pos,
                    byte[] bytes,
                    int offset,
                    int len)
             throws SQLException

Writes all or part of the given byte array to the BLOB value that this Blob object represents and returns the number of bytes written.

Specified by:

setBytes in interface Blob

Parameters:

pos - the position in the BLOB object at which to start writing

bytes - the array of bytes to be written to this BLOB object

offset - the offset into the array bytes at which to start reading the bytes to be set

len - the number of bytes to be written to the BLOB value from the array of bytes bytes

Returns:

the number of bytes written

Throws:

SQLException - if there is an error accessing the BLOB value

setBinaryStream

public OutputStream setBinaryStream(long pos)
                             throws SQLException

Retrieves a stream that can be used to write to the BLOB value that this Blob object represents.

Specified by:

setBinaryStream in interface Blob

Parameters:

pos - the position in the BLOB value at which to start writing

Returns:

a java.io.OutputStream object to which data can be written

Throws:

SQLException - if there is an error accessing the BLOB value

truncate

public void truncate(long len)
              throws SQLException

Truncates the BLOB value that this Blob object represents to be len bytes in length.

Specified by:

truncate in interface Blob

Parameters:

len - the length, in bytes, to which the BLOB value that this Blob object represents should be truncated

Throws:

SQLException - if there is an error accessing the BLOB value

free

public void free()
          throws SQLException

This method frees the Blob object and releases the resources that it holds. The object is invalid once the free method is called.

After free has been called, any attempt to invoke a method other than free will result in a SQLException being thrown. If free is called multiple times, the subsequent calls to free are treated as a no-op.

Specified by:

free in interface Blob

Throws:

SQLException - if an error occurs releasing the Blob's resources

SQLFeatureNotSupportedException - if the JDBC driver does not support this method

Since:

JDK 1.6, HSQLDB 2.0

getBinaryStream

public InputStream getBinaryStream(long pos,
                                   long length)
                            throws SQLException

Returns an InputStream object that contains a partial Blob value, starting with the byte specified by pos, which is length bytes in length.

Specified by:

getBinaryStream in interface Blob

Parameters:

pos - the offset to the first byte of the partial value to be retrieved. The first byte in the Blob is at position 1

length - the length in bytes of the partial value to be retrieved

Returns:

InputStream through which the partial Blob value can be read.

Throws:

SQLException - if pos is less than 1 or if pos is greater than the number of bytes in the Blob or if pos + length is greater than the number of bytes in the Blob

SQLFeatureNotSupportedException - if the JDBC driver does not support this method

Since:

JDK 1.6, HSQLDB 2.0

isClosed

public boolean isClosed()

getBlob

public org.hsqldb.types.BlobDataID getBlob()

setWritable

public void setWritable(JDBCResultSet result,
                        int index)

clearUpdates

public void clearUpdates()