001/**
002 * Licensed to the Apache Software Foundation (ASF) under one or more
003 * contributor license agreements.  See the NOTICE file distributed with
004 * this work for additional information regarding copyright ownership.
005 * The ASF licenses this file to You under the Apache License, Version 2.0
006 * (the "License"); you may not use this file except in compliance with
007 * the License.  You may obtain a copy of the License at
008 *
009 *      http://www.apache.org/licenses/LICENSE-2.0
010 *
011 * Unless required by applicable law or agreed to in writing, software
012 * distributed under the License is distributed on an "AS IS" BASIS,
013 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
014 * See the License for the specific language governing permissions and
015 * limitations under the License.
016 */
017package org.apache.activemq.jndi;
018
019import java.io.Externalizable;
020import java.io.IOException;
021import java.io.ObjectInput;
022import java.io.ObjectOutput;
023import java.util.Properties;
024
025import javax.naming.NamingException;
026import javax.naming.Reference;
027
028/**
029 * Facilitates objects to be stored in JNDI as properties
030 */
031
032public abstract class JNDIBaseStorable implements JNDIStorableInterface, Externalizable {
033
034    private Properties properties;
035
036    /**
037     * Set the properties that will represent the instance in JNDI
038     * 
039     * @param props
040     */
041    protected abstract void buildFromProperties(Properties props);
042
043    /**
044     * Initialize the instance from properties stored in JNDI
045     * 
046     * @param props
047     */
048
049    protected abstract void populateProperties(Properties props);
050
051    /**
052     * set the properties for this instance as retrieved from JNDI
053     * 
054     * @param props
055     */
056
057    public synchronized void setProperties(Properties props) {
058        this.properties = props;
059        buildFromProperties(props);
060    }
061
062    /**
063     * Get the properties from this instance for storing in JNDI
064     * 
065     * @return the properties
066     */
067
068    public synchronized Properties getProperties() {
069        if (this.properties == null) {
070            this.properties = new Properties();
071        }
072        populateProperties(this.properties);
073        return this.properties;
074    }
075
076    /**
077     * Retrive a Reference for this instance to store in JNDI
078     * 
079     * @return the built Reference
080     * @throws NamingException if error on building Reference
081     */
082    public Reference getReference() throws NamingException {
083        return JNDIReferenceFactory.createReference(this.getClass().getName(), this);
084    }
085
086    /**
087     * @param in
088     * @throws IOException
089     * @throws ClassNotFoundException
090     * @see java.io.Externalizable#readExternal(java.io.ObjectInput)
091     */
092    public void readExternal(ObjectInput in) throws IOException, ClassNotFoundException {
093        Properties props = (Properties)in.readObject();
094        if (props != null) {
095            setProperties(props);
096        }
097
098    }
099
100    /**
101     * @param out
102     * @throws IOException
103     * @see java.io.Externalizable#writeExternal(java.io.ObjectOutput)
104     */
105    public void writeExternal(ObjectOutput out) throws IOException {
106        out.writeObject(getProperties());
107
108    }
109
110}