blobfromlocator.java

mysql5.0 JDBC 驱动 放在glassfish或者tomcat的lib文件夹下就可以了

				try {
					pStmt.close();
				} catch (SQLException sqlEx) {
					; // do nothing
				}

				pStmt = null;
			}
		}
	}

	/**
	 * Finds the position of the given pattern in this BLOB.
	 * 
	 * @param pattern
	 *            the pattern to find
	 * @param start
	 *            where to start finding the pattern
	 * 
	 * @return the position where the pattern is found in the BLOB, -1 if not
	 *         found
	 * 
	 * @throws SQLException
	 *             if a database error occurs
	 */
	public long position(java.sql.Blob pattern, long start) throws SQLException {
		return position(pattern.getBytes(0, (int) pattern.length()), start);
	}

	/**
	 * @see java.sql.Blob#position(byte[], long)
	 */
	public long position(byte[] pattern, long start) throws SQLException {
		java.sql.ResultSet blobRs = null;
		java.sql.PreparedStatement pStmt = null;

		// FIXME: Needs to use identifiers for column/table names
		StringBuffer query = new StringBuffer("SELECT LOCATE(");
		query.append("?, ");
		query.append(this.blobColumnName);
		query.append(", ");
		query.append(start);
		query.append(") FROM ");
		query.append(this.tableName);
		query.append(" WHERE ");

		query.append((String) this.primaryKeyColumns.get(0));
		query.append(" = ?");

		for (int i = 1; i < this.numPrimaryKeys; i++) {
			query.append(" AND ");
			query.append((String) this.primaryKeyColumns.get(i));
			query.append(" = ?");
		}

		try {
			// FIXME: Have this passed in instead
			pStmt = this.creatorResultSet.connection.prepareStatement(query
					.toString());
			pStmt.setBytes(1, pattern);

			for (int i = 0; i < this.numPrimaryKeys; i++) {
				pStmt.setString(i + 2, (String) this.primaryKeyValues.get(i));
			}

			blobRs = pStmt.executeQuery();

			if (blobRs.next()) {
				return blobRs.getLong(1);
			}

			throw SQLError.createSQLException(
					"BLOB data not found! Did primary keys change?",
					SQLError.SQL_STATE_GENERAL_ERROR);
		} finally {
			if (blobRs != null) {
				try {
					blobRs.close();
				} catch (SQLException sqlEx) {
					; // do nothing
				}

				blobRs = null;
			}

			if (pStmt != null) {
				try {
					pStmt.close();
				} catch (SQLException sqlEx) {
					; // do nothing
				}

				pStmt = null;
			}
		}
	}

	/**
	 * @see Blob#truncate(long)
	 */
	public void truncate(long length) throws SQLException {
		java.sql.PreparedStatement pStmt = null;

		// FIXME: Needs to use identifiers for column/table names
		StringBuffer query = new StringBuffer("UPDATE ");
		query.append(this.tableName);
		query.append(" SET ");
		query.append(this.blobColumnName);
		query.append(" = LEFT(");
		query.append(this.blobColumnName);
		query.append(", ");
		query.append(length);
		query.append(") WHERE ");

		query.append((String) this.primaryKeyColumns.get(0));
		query.append(" = ?");

		for (int i = 1; i < this.numPrimaryKeys; i++) {
			query.append(" AND ");
			query.append((String) this.primaryKeyColumns.get(i));
			query.append(" = ?");
		}

		try {
			// FIXME: Have this passed in instead
			pStmt = this.creatorResultSet.connection.prepareStatement(query
					.toString());

			for (int i = 0; i < this.numPrimaryKeys; i++) {
				pStmt.setString(i + 1, (String) this.primaryKeyValues.get(i));
			}

			int rowsUpdated = pStmt.executeUpdate();

			if (rowsUpdated != 1) {
				throw SQLError.createSQLException(
						"BLOB data not found! Did primary keys change?",
						SQLError.SQL_STATE_GENERAL_ERROR);
			}
		} finally {
			if (pStmt != null) {
				try {
					pStmt.close();
				} catch (SQLException sqlEx) {
					; // do nothing
				}

				pStmt = null;
			}
		}
	}

	java.sql.PreparedStatement createGetBytesStatement() throws SQLException {
		StringBuffer query = new StringBuffer("SELECT SUBSTRING(");

		query.append(this.blobColumnName);
		query.append(", ");
		query.append("?");
		query.append(", ");
		query.append("?");
		query.append(") FROM ");
		query.append(this.tableName);
		query.append(" WHERE ");

		query.append((String) this.primaryKeyColumns.get(0));
		query.append(" = ?");

		for (int i = 1; i < this.numPrimaryKeys; i++) {
			query.append(" AND ");
			query.append((String) this.primaryKeyColumns.get(i));
			query.append(" = ?");
		}

		return this.creatorResultSet.connection.prepareStatement(query
				.toString());
	}

	byte[] getBytesInternal(java.sql.PreparedStatement pStmt, long pos,
			int length) throws SQLException {

		java.sql.ResultSet blobRs = null;

		try {

			pStmt.setLong(1, pos);
			pStmt.setInt(2, length);

			for (int i = 0; i < this.numPrimaryKeys; i++) {
				pStmt.setString(i + 3, (String) this.primaryKeyValues.get(i));
			}

			blobRs = pStmt.executeQuery();

			if (blobRs.next()) {
				return ((com.mysql.jdbc.ResultSetImpl) blobRs).getBytes(1, true);
			}

			throw SQLError.createSQLException(
					"BLOB data not found! Did primary keys change?",
					SQLError.SQL_STATE_GENERAL_ERROR);
		} finally {
			if (blobRs != null) {
				try {
					blobRs.close();
				} catch (SQLException sqlEx) {
					; // do nothing
				}

				blobRs = null;
			}
		}
	}

	class LocatorInputStream extends InputStream {
		long currentPositionInBlob = 0;

		long length = 0;

		java.sql.PreparedStatement pStmt = null;

		LocatorInputStream() throws SQLException {
			length = length();
			pStmt = createGetBytesStatement();
		}

		LocatorInputStream(long pos, long len) throws SQLException {
			length = pos + len;
			currentPositionInBlob = pos;
			long blobLength = length();
			
			if (pos + len > blobLength) {
				throw SQLError.createSQLException(
						Messages.getString("Blob.invalidStreamLength", 
								new Object[] {new Long(blobLength), new Long(pos), new Long(len)}),
								SQLError.SQL_STATE_ILLEGAL_ARGUMENT);
			}
			
			if (pos < 1) {
				throw SQLError.createSQLException(Messages.getString("Blob.invalidStreamPos"), 
						SQLError.SQL_STATE_ILLEGAL_ARGUMENT);
			}
			
			if (pos > blobLength) {
				throw SQLError.createSQLException(Messages.getString("Blob.invalidStreamPos"), 
						SQLError.SQL_STATE_ILLEGAL_ARGUMENT);
			}
		}
		
		public int read() throws IOException {
			if (currentPositionInBlob + 1 > length) {
				return -1;
			}

			try {
				byte[] asBytes = getBytesInternal(pStmt,
						(currentPositionInBlob++) + 1, 1);

				if (asBytes == null) {
					return -1;
				}

				return asBytes[0];
			} catch (SQLException sqlEx) {
				throw new IOException(sqlEx.toString());
			}
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see java.io.InputStream#read(byte[], int, int)
		 */
		public int read(byte[] b, int off, int len) throws IOException {
			if (currentPositionInBlob + 1 > length) {
				return -1;
			}

			try {
				byte[] asBytes = getBytesInternal(pStmt,
						(currentPositionInBlob) + 1, len);

				if (asBytes == null) {
					return -1;
				}

				System.arraycopy(asBytes, 0, b, off, asBytes.length);

				currentPositionInBlob += asBytes.length;

				return asBytes.length;
			} catch (SQLException sqlEx) {
				throw new IOException(sqlEx.toString());
			}
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see java.io.InputStream#read(byte[])
		 */
		public int read(byte[] b) throws IOException {
			if (currentPositionInBlob + 1 > length) {
				return -1;
			}

			try {
				byte[] asBytes = getBytesInternal(pStmt,
						(currentPositionInBlob) + 1, b.length);

				if (asBytes == null) {
					return -1;
				}

				System.arraycopy(asBytes, 0, b, 0, asBytes.length);

				currentPositionInBlob += asBytes.length;

				return asBytes.length;
			} catch (SQLException sqlEx) {
				throw new IOException(sqlEx.toString());
			}
		}

		/*
		 * (non-Javadoc)
		 * 
		 * @see java.io.InputStream#close()
		 */
		public void close() throws IOException {
			if (pStmt != null) {
				try {
					pStmt.close();
				} catch (SQLException sqlEx) {
					throw new IOException(sqlEx.toString());
				}
			}

			super.close();
		}
	}

	public void free() throws SQLException {
		this.creatorResultSet = null;
		this.primaryKeyColumns = null;
		this.primaryKeyValues = null;
	}

	public InputStream getBinaryStream(long pos, long length) throws SQLException {
		return new LocatorInputStream(pos, length);
	}
}