org.drizzle.jdbc
Class DrizzleBlob

java.lang.Object
  java.io.OutputStream
      org.drizzle.jdbc.DrizzleBlob

All Implemented Interfaces:

java.io.Closeable, java.io.Flushable, java.sql.Blob

public final class DrizzleBlob
extends java.io.OutputStream
implements java.sql.Blob

Represents a Blob.

User: marcuse Date: Feb 14, 2009 Time: 9:40:54 PM

Constructor Summary

DrizzleBlob()
creates an empty blob.

DrizzleBlob(byte[] bytes)
creates a blob with content.

Method Summary

void	free() This method frees the Blob object and releases the resources that it holds.
java.io.InputStream	getBinaryStream() Retrieves the BLOB value designated by this Blob instance as a stream.
java.io.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.
byte[]	getBytes(long pos, int length) Retrieves all or part of the BLOB value that this Blob object represents, as an array of bytes.
long	length() Returns the number of bytes in the BLOB value designated by this Blob object.
long	position(java.sql.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.
java.io.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	truncate(long len) Truncates the BLOB value that this Blob object represents to be len bytes in length.
void	write(int b) Writes the specified byte to this output stream.

Methods inherited from class java.io.OutputStream

close, flush, write, write

Methods inherited from class java.lang.Object

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

Constructor Detail

DrizzleBlob

public DrizzleBlob()

creates an empty blob.

DrizzleBlob

public DrizzleBlob(byte[] bytes)

creates a blob with content.

Parameters:

bytes - the content for the blob.

Method Detail

write

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

Writes the specified byte to this output stream. The general contract for write is that one byte is written to the output stream. The byte to be written is the eight low-order bits of the argument b. The 24 high-order bits of b are ignored.

Subclasses of OutputStream must provide an implementation for this method.

Specified by:

write in class java.io.OutputStream

Parameters:

b - the byte.

Throws:

java.io.IOException - if an I/O error occurs. In particular, an IOException may be thrown if the output stream has been closed.

length

public long length()
            throws java.sql.SQLException

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

Specified by:

length in interface java.sql.Blob

Returns:

length of the BLOB in bytes

Throws:

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

getBytes

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

Retrieves all or part of the BLOB value that this Blob object represents, as an array of bytes. This byte array contains up to length consecutive bytes starting at position pos.

Specified by:

getBytes in interface java.sql.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; the value for length must be 0 or greater

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:

java.sql.SQLException - if there is an error accessing the BLOB value; if pos is less than 1 or length is less than 0

Since:

1.2

See Also:

setBytes(long, byte[])

getBinaryStream

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

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

Specified by:

getBinaryStream in interface java.sql.Blob

Returns:

a stream containing the BLOB data

Throws:

java.sql.SQLException - if something went wrong

See Also:

setBinaryStream(long)

position

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

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

Specified by:

position in interface java.sql.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:

java.sql.SQLException

position

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

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

Specified by:

position in interface java.sql.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:

java.sql.SQLException

setBytes

public int setBytes(long pos,
                    byte[] bytes)
             throws java.sql.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. The array of bytes will overwrite the existing bytes in the Blob object starting at the position pos. If the end of the Blob value is reached while writing the array of bytes, then the length of the Blob value will be increased to accomodate the extra bytes.

Note: If the value specified for pos is greater then the length+1 of the BLOB value then the behavior is undefined. Some JDBC drivers may throw a SQLException while other drivers may support this operation.

Specified by:

setBytes in interface java.sql.Blob

Parameters:

pos - the position in the BLOB object at which to start writing; the first position is 1

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

Returns:

the number of bytes written

Throws:

java.sql.SQLException

Since:

1.4

See Also:

getBytes(long, int)

setBytes

public int setBytes(long pos,
                    byte[] bytes,
                    int offset,
                    int len)
             throws java.sql.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. Writing starts at position pos in the BLOB value; len bytes from the given byte array are written. The array of bytes will overwrite the existing bytes in the Blob object starting at the position pos. If the end of the Blob value is reached while writing the array of bytes, then the length of the Blob value will be increased to accomodate the extra bytes.

Note: If the value specified for pos is greater then the length+1 of the BLOB value then the behavior is undefined. Some JDBC drivers may throw a SQLException while other drivers may support this operation.

Specified by:

setBytes in interface java.sql.Blob

Parameters:

pos - the position in the BLOB object at which to start writing; the first position is 1

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:

java.sql.SQLException - if there is an error accessing the BLOB value or if pos is less than 1

See Also:

getBytes(long, int)

setBinaryStream

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

Retrieves a stream that can be used to write to the BLOB value that this Blob object represents. The stream begins at position pos. The bytes written to the stream will overwrite the existing bytes in the Blob object starting at the position pos. If the end of the Blob value is reached while writing to the stream, then the length of the Blob value will be increased to accomodate the extra bytes.

Note: If the value specified for pos is greater then the length+1 of the BLOB value then the behavior is undefined. Some JDBC drivers may throw a SQLException while other drivers may support this operation.

Specified by:

setBinaryStream in interface java.sql.Blob

Parameters:

pos - the position in the BLOB value at which to start writing; the first position is 1

Returns:

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

Throws:

java.sql.SQLException - if there is an error accessing the BLOB value or if pos is less than 1

Since:

1.4

See Also:

getBinaryStream()

truncate

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

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

Note: If the value specified for pos is greater then the length+1 of the BLOB value then the behavior is undefined. Some JDBC drivers may throw a SQLException while other drivers may support this operation.

Specified by:

truncate in interface java.sql.Blob

Parameters:

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

Throws:

java.sql.SQLException - if there is an error accessing the BLOB value or if len is less than 0

free

public void free()

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 java.sql.Blob

getBinaryStream

public java.io.InputStream getBinaryStream(long pos,
                                           long length)
                                    throws java.sql.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 java.sql.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:

java.sql.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