https://openjdk.java.net/ 
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 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
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package java.sql;

import java.io.InputStream;


The representation (mapping) in
the Java™ programming
language of an SQL
BLOB value.  An SQL BLOB is a built-in type
that stores a Binary Large Object as a column value in a row of
a database table. By default drivers implement Blob using
an SQL locator(BLOB), which means that a
Blob object contains a logical pointer to the
SQL BLOB data rather than the data itself.
A Blob object is valid for the duration of the
transaction in which is was created.

Methods in the interfaces ResultSet, CallableStatement, and PreparedStatement, such as getBlob and setBlob allow a programmer to
access an SQL BLOB value.
The Blob interface provides methods for getting the
length of an SQL BLOB (Binary Large Object) value,
for materializing a BLOB value on the client, and for
determining the position of a pattern of bytes within a
BLOB value. In addition, this interface has methods for updating
a BLOB value.


All methods on the Blob interface must be fully implemented if the
JDBC driver supports the data type.

Since:1.2
/**
 * The representation (mapping) in
 * the Java™ programming
 * language of an SQL
 * <code>BLOB</code> value.  An SQL <code>BLOB</code> is a built-in type
 * that stores a Binary Large Object as a column value in a row of
 * a database table. By default drivers implement <code>Blob</code> using
 * an SQL <code>locator(BLOB)</code>, which means that a
 * <code>Blob</code> object contains a logical pointer to the
 * SQL <code>BLOB</code> data rather than the data itself.
 * A <code>Blob</code> object is valid for the duration of the
 * transaction in which is was created.
 *
 * <P>Methods in the interfaces {@link ResultSet},
 * {@link CallableStatement}, and {@link PreparedStatement}, such as
 * <code>getBlob</code> and <code>setBlob</code> allow a programmer to
 * access an SQL <code>BLOB</code> value.
 * The <code>Blob</code> interface provides methods for getting the
 * length of an SQL <code>BLOB</code> (Binary Large Object) value,
 * for materializing a <code>BLOB</code> value on the client, and for
 * determining the position of a pattern of bytes within a
 * <code>BLOB</code> value. In addition, this interface has methods for updating
 * a <code>BLOB</code> value.
 * <p>
 * All methods on the <code>Blob</code> interface must be fully implemented if the
 * JDBC driver supports the data type.
 *
 * @since 1.2
 */

public interface Blob {

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

Throws:
Returns:length of the BLOB in bytes
Since:1.2
/**
   * Returns the number of bytes in the <code>BLOB</code> value
   * designated by this <code>Blob</code> object.
   * @return length of the <code>BLOB</code> in bytes
   * @exception SQLException if there is an error accessing the
   * length of the <code>BLOB</code>
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  long length() throws 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.

Params:
  • 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
Throws:
See Also:
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
Since:1.2
/**
   * Retrieves all or part of the <code>BLOB</code>
   * value that this <code>Blob</code> object represents, as an array of
   * bytes.  This <code>byte</code> array contains up to <code>length</code>
   * consecutive bytes starting at position <code>pos</code>.
   *
   * @param pos the ordinal position of the first byte in the
   *        <code>BLOB</code> value to be extracted; the first byte is at
   *        position 1
   * @param length the number of consecutive bytes to be copied; the value
   * for length must be 0 or greater
   * @return a byte array containing up to <code>length</code>
   *         consecutive bytes from the <code>BLOB</code> value designated
   *         by this <code>Blob</code> object, starting with the
   *         byte at position <code>pos</code>
   * @exception SQLException if there is an error accessing the
   *            <code>BLOB</code> value; if pos is less than 1 or length is
   * less than 0
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @see #setBytes
   * @since 1.2
   */
  byte[] getBytes(long pos, int length) throws SQLException;

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

Throws:
See Also:
Returns:a stream containing the BLOB data
Since:1.2
/**
   * Retrieves the <code>BLOB</code> value designated by this
   * <code>Blob</code> instance as a stream.
   *
   * @return a stream containing the <code>BLOB</code> data
   * @exception SQLException if there is an error accessing the
   *            <code>BLOB</code> value
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @see #setBinaryStream
   * @since 1.2
   */
  java.io.InputStream getBinaryStream () throws 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.

Params:
  • pattern – the byte array for which to search
  • start – the position at which to begin searching; the
       first position is 1
Throws:
Returns:the position at which the pattern appears, else -1
Since:1.2
/**
   * Retrieves the byte position at which the specified byte array
   * <code>pattern</code> begins within the <code>BLOB</code>
   * value that this <code>Blob</code> object represents.  The
   * search for <code>pattern</code> begins at position
   * <code>start</code>.
   *
   * @param pattern the byte array for which to search
   * @param start the position at which to begin searching; the
   *        first position is 1
   * @return the position at which the pattern appears, else -1
   * @exception SQLException if there is an error accessing the
   * <code>BLOB</code> or if start is less than 1
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  long position(byte pattern[], long start) throws SQLException;

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

Params:
  • 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
Throws:
Returns:the position at which the pattern begins, else -1
Since:1.2
/**
   * Retrieves the byte position in the <code>BLOB</code> value
   * designated by this <code>Blob</code> object at which
   * <code>pattern</code> begins.  The search begins at position
   * <code>start</code>.
   *
   * @param pattern the <code>Blob</code> object designating
   * the <code>BLOB</code> value for which to search
   * @param start the position in the <code>BLOB</code> value
   *        at which to begin searching; the first position is 1
   * @return the position at which the pattern begins, else -1
   * @exception SQLException if there is an error accessing the
   *            <code>BLOB</code> value or if start is less than 1
   * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
   * this method
   * @since 1.2
   */
  long position(Blob pattern, long start) throws SQLException;

    // -------------------------- JDBC 3.0 -----------------------------------

    
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 accommodate 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.

Params:
  • 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
Throws:
See Also:
Returns:the number of bytes written
Since:1.4
/**
     * Writes the given array of bytes to the <code>BLOB</code> value that
     * this <code>Blob</code> object represents, starting at position
     * <code>pos</code>, and returns the number of bytes written.
     * The array of bytes will overwrite the existing bytes
     * in the <code>Blob</code> object starting at the position
     * <code>pos</code>.  If the end of the <code>Blob</code> value is reached
     * while writing the array of bytes, then the length of the <code>Blob</code>
     * value will be increased to accommodate the extra bytes.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>BLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param pos the position in the <code>BLOB</code> object at which
     *        to start writing; the first position is 1
     * @param bytes the array of bytes to be written to the <code>BLOB</code>
     *        value that this <code>Blob</code> object represents
     * @return the number of bytes written
     * @exception SQLException if there is an error accessing the
     *            <code>BLOB</code> value or if pos is less than 1
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @see #getBytes
     * @since 1.4
     */
    int setBytes(long pos, byte[] bytes) 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.
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 accommodate 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.

Params:
  • 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
Throws:
See Also:
Returns:the number of bytes written
Since:1.4
/**
     * Writes all or part of the given <code>byte</code> array to the
     * <code>BLOB</code> value that this <code>Blob</code> object represents
     * and returns the number of bytes written.
     * Writing starts at position <code>pos</code> in the <code>BLOB</code>
     * value; <code>len</code> bytes from the given byte array are written.
     * The array of bytes will overwrite the existing bytes
     * in the <code>Blob</code> object starting at the position
     * <code>pos</code>.  If the end of the <code>Blob</code> value is reached
     * while writing the array of bytes, then the length of the <code>Blob</code>
     * value will be increased to accommodate the extra bytes.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>BLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param pos the position in the <code>BLOB</code> object at which
     *        to start writing; the first position is 1
     * @param bytes the array of bytes to be written to this <code>BLOB</code>
     *        object
     * @param offset the offset into the array <code>bytes</code> at which
     *        to start reading the bytes to be set
     * @param len the number of bytes to be written to the <code>BLOB</code>
     *        value from the array of bytes <code>bytes</code>
     * @return the number of bytes written
     * @exception SQLException if there is an error accessing the
     *            <code>BLOB</code> value or if pos is less than 1
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @see #getBytes
     * @since 1.4
     */
    int setBytes(long pos, byte[] bytes, int offset, int len) throws 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 accommodate 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.

Params:
  • pos – the position in the BLOB value at which
       to start writing; the first position is 1
Throws:
See Also:
Returns:a java.io.OutputStream object to which data can
        be written
Since:1.4
/**
     * Retrieves a stream that can be used to write to the <code>BLOB</code>
     * value that this <code>Blob</code> object represents.  The stream begins
     * at position <code>pos</code>.
     * The  bytes written to the stream will overwrite the existing bytes
     * in the <code>Blob</code> object starting at the position
     * <code>pos</code>.  If the end of the <code>Blob</code> value is reached
     * while writing to the stream, then the length of the <code>Blob</code>
     * value will be increased to accommodate the extra bytes.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>BLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param pos the position in the <code>BLOB</code> value at which
     *        to start writing; the first position is 1
     * @return a <code>java.io.OutputStream</code> object to which data can
     *         be written
     * @exception SQLException if there is an error accessing the
     *            <code>BLOB</code> value or if pos is less than 1
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @see #getBinaryStream
     * @since 1.4
     */
    java.io.OutputStream setBinaryStream(long pos) throws 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.

Params:
  • len – the length, in bytes, to which the BLOB value
       that this Blob object represents should be truncated
Throws:
Since:1.4
/**
     * Truncates the <code>BLOB</code> value that this <code>Blob</code>
     * object represents to be <code>len</code> bytes in length.
     * <p>
     * <b>Note:</b> If the value specified for <code>pos</code>
     * is greater then the length+1 of the <code>BLOB</code> value then the
     * behavior is undefined. Some JDBC drivers may throw a
     * <code>SQLException</code> while other drivers may support this
     * operation.
     *
     * @param len the length, in bytes, to which the <code>BLOB</code> value
     *        that this <code>Blob</code> object represents should be truncated
     * @exception SQLException if there is an error accessing the
     *            <code>BLOB</code> value or if len is less than 0
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @since 1.4
     */
    void truncate(long len) 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.



Throws:
Since:1.6
/**
     * This method frees the <code>Blob</code> object and releases the resources that
     * it holds. The object is invalid once the <code>free</code>
     * method is called.
     *<p>
     * After <code>free</code> has been called, any attempt to invoke a
     * method other than <code>free</code> will result in a <code>SQLException</code>
     * being thrown.  If <code>free</code> is called multiple times, the subsequent
     * calls to <code>free</code> are treated as a no-op.
     *<p>
     *
     * @throws SQLException if an error occurs releasing
     * the Blob's resources
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @since 1.6
     */
    void free() 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.

Params:
  • 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
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
Returns:InputStream through which the partial Blob value can be read.
Since:1.6
/**
     * Returns an <code>InputStream</code> object that contains a partial <code>Blob</code> value,
     * starting  with the byte specified by pos, which is length bytes in length.
     *
     * @param pos the offset to the first byte of the partial value to be retrieved.
     *  The first byte in the <code>Blob</code> is at position 1
     * @param length the length in bytes of the partial value to be retrieved
     * @return <code>InputStream</code> through which the partial <code>Blob</code> value can be read.
     * @throws SQLException if pos is less than 1 or if pos is greater than the number of bytes
     * in the <code>Blob</code> or if pos + length is greater than the number of bytes
     * in the <code>Blob</code>
     *
     * @exception SQLFeatureNotSupportedException if the JDBC driver does not support
     * this method
     * @since 1.6
     */
    InputStream getBinaryStream(long pos, long length) throws SQLException;
}