/*
* @(#)Blob.java 1.28 03/12/19
*
* Copyright 2004 Sun Microsystems, Inc. All rights reserved.
* SUN PROPRIETARY/CONFIDENTIAL. Use is subject to license terms.
*/
package java.sql;
/**
* The representation (mapping) in
* the Java<sup><font size=-2>TM</font></sup> 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.
*
* @since 1.2
*/
public interface Blob {
/**
* 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>
* @since 1.2
*/
long length() throws SQLException;
/**
* 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
* @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
* @see #setBytes
* @since 1.2
*/
byte[] getBytes(long pos, int length) throws SQLException;
/**
* 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
* @see #setBinaryStream
* @since 1.2
*/
java.io.InputStream getBinaryStream () throws SQLException;
/**
* 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>
* @since 1.2
*/
long position(byte pattern[], long start) throws SQLException;
/**
* 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
* @since 1.2
*/
long position(Blob pattern, long start) throws SQLException;
// -------------------------- JDBC 3.0 -----------------------------------
/**
* 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.
*
* @param pos the position in the <code>BLOB</code> object at which
* to start writing
* @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
* @see #getBytes
* @since 1.4
*/
int setBytes(long pos, byte[] bytes) throws SQLException;
/**
* 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.
*
* @param pos the position in the <code>BLOB</code> object at which
* to start writing
* @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
* @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 <code>BLOB</code>
* value that this <code>Blob</code> object represents. The stream begins
* at position <code>pos</code>.
*
* @param pos the position in the <code>BLOB</code> value at which
* to start writing
* @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
* @see #getBinaryStream
* @since 1.4
*/
java.io.OutputStream setBinaryStream(long pos) throws SQLException;
/**
* Truncates the <code>BLOB</code> value that this <code>Blob</code>
* object represents to be <code>len</code> bytes in length.
*
* @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
* @since 1.4
*/
void truncate(long len) throws SQLException;
}
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