ActiveMQ example source code file (BlobJDBCAdapter.java)

This example ActiveMQ source code file (BlobJDBCAdapter.java) is included in the DevDaily.com "Java Source Code Warehouse" project. The intent of this project is to help you "Learn Java by Example" ^TM.

Java - ActiveMQ tags/keywords

blob, blob, blobjdbcadapter, failed, io, ioexception, jdbc, jmsexception, jmsexception, preparedstatement, resultset, sql, sqlexception, sqlexception, string, throwable, throwable

The ActiveMQ BlobJDBCAdapter.java source code

/**
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF licenses this file to You under the Apache License, Version 2.0
 * (the "License"); you may not use this file except in compliance with
 * the License.  You may obtain a copy of the License at
 *
 *      http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package org.apache.activemq.store.jdbc.adapter;

import java.io.IOException;
import java.io.InputStream;
import java.io.OutputStream;
import java.sql.Blob;
import java.sql.Connection;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;

import javax.jms.JMSException;

import org.apache.activemq.store.jdbc.TransactionContext;
import org.apache.activemq.util.ByteArrayOutputStream;

/**
 * This JDBCAdapter inserts and extracts BLOB data using the getBlob()/setBlob()
 * operations. This is a little more involved since to insert a blob you have
 * to:
 * 
 * 1: insert empty blob. 2: select the blob 3: finally update the blob with data
 * value.
 * 
 * The databases/JDBC drivers that use this adapter are:
 * <ul>
 * <li>
 * </ul>
 * 
 * @org.apache.xbean.XBean element="blobJDBCAdapter"
 * 
 * 
 */
public class BlobJDBCAdapter extends DefaultJDBCAdapter {

    public void doAddMessage(Connection c, long seq, String messageID, String destinationName, byte[] data)
        throws SQLException, JMSException {
        PreparedStatement s = null;
        ResultSet rs = null;
        try {

            // Add the Blob record.
            s = c.prepareStatement(statements.getAddMessageStatement());
            s.setLong(1, seq);
            s.setString(2, destinationName);
            s.setString(3, messageID);
            s.setString(4, " ");

            if (s.executeUpdate() != 1) {
                throw new JMSException("Failed to broker message: " + messageID + " in container.");
            }
            s.close();

            // Select the blob record so that we can update it.
            s = c.prepareStatement(statements.getFindMessageStatement());
            s.setLong(1, seq);
            rs = s.executeQuery();
            if (!rs.next()) {
                throw new JMSException("Failed to broker message: " + messageID + " in container.");
            }

            // Update the blob
            Blob blob = rs.getBlob(1);
            OutputStream stream = blob.setBinaryStream(data.length);
            stream.write(data);
            stream.close();
            s.close();

            // Update the row with the updated blob
            s = c.prepareStatement(statements.getUpdateMessageStatement());
            s.setBlob(1, blob);
            s.setLong(2, seq);

        } catch (IOException e) {
            throw (SQLException)new SQLException("BLOB could not be updated: " + e).initCause(e);
        } finally {
            try {
                rs.close();
            } catch (Throwable ignore) {
            }
            try {
                s.close();
            } catch (Throwable ignore) {
            }
        }
    }

    public byte[] doGetMessage(TransactionContext c, long seq) throws SQLException {
        PreparedStatement s = null;
        ResultSet rs = null;
        try {

            s = c.getConnection().prepareStatement(statements.getFindMessageStatement());
            s.setLong(1, seq);
            rs = s.executeQuery();

            if (!rs.next()) {
                return null;
            }
            Blob blob = rs.getBlob(1);
            InputStream is = blob.getBinaryStream();

            ByteArrayOutputStream os = new ByteArrayOutputStream((int)blob.length());
            int ch;
            while ((ch = is.read()) >= 0) {
                os.write(ch);
            }
            is.close();
            os.close();

            return os.toByteArray();

        } catch (IOException e) {
            throw (SQLException)new SQLException("BLOB could not be updated: " + e).initCause(e);
        } finally {
            try {
                rs.close();
            } catch (Throwable ignore) {
            }
            try {
                s.close();
            } catch (Throwable ignore) {
            }
        }
    }

}