updateserviceproperties.java

derby database source code.good for you.

/*

   Derby - Class org.apache.derby.impl.services.monitor.UpdateServiceProperties

   Copyright 1998, 2004 The Apache Software Foundation or its licensors, as applicable.

   Licensed 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.derby.impl.services.monitor;

import org.apache.derby.iapi.services.monitor.PersistentService;
import org.apache.derby.iapi.services.sanity.SanityManager;

import java.util.Properties;
import java.util.Hashtable;
import org.apache.derby.io.WritableStorageFactory;

import org.apache.derby.iapi.error.StandardException;
import org.apache.derby.iapi.error.PassThroughException;
import org.apache.derby.iapi.reference.Property;

/**
*/
public class UpdateServiceProperties extends Properties {

	private PersistentService serviceType;
	private String serviceName;
    private WritableStorageFactory storageFactory;
    
	/*
	Fix for bug 3668: Following would allow user to change properties while in the session
	in which the database was created.
	While the database is being created, serviceBooted would be false. What that means
	is, don't save changes into services.properties file from here until the database
	is created. Instead, let BaseMonitor save the properties at the end of the database
  creation and also set serviceBooted to true at that point. From then on, the
  services.properties file updates will be made here.
	*/
	private boolean serviceBooted;

	public UpdateServiceProperties(PersistentService serviceType, String serviceName,
	Properties actualSet, boolean serviceBooted) {
		super(actualSet);
		this.serviceType = serviceType;
		this.serviceName = serviceName;
		this.serviceBooted = serviceBooted;
	}

	//look at the comments for serviceBooted at the top to understand this.
	public void setServiceBooted() {
		serviceBooted = true;
	}

    public void setStorageFactory( WritableStorageFactory storageFactory)
    {
        this.storageFactory = storageFactory;
    }

    public WritableStorageFactory getStorageFactory()
    {
        return storageFactory;
    }
    
	/*
	** Methods of Hashtable (overridden)
	*/

	/**	
		Put the key-value pair in the Properties set and
		mark this set as modified.

		@see Hashtable#put
	*/
	public Object put(Object key, Object value) {
		Object ref = defaults.put(key, value);
		if (!((String) key).startsWith(Property.PROPERTY_RUNTIME_PREFIX))
			update();
		return ref;
	}

	/**	
		Remove the key-value pair from the Properties set and
		mark this set as modified.

		@see Hashtable#remove
	*/
	public Object remove(Object key) {
		Object ref = defaults.remove(key);
		if ((ref != null) &&
			(!((String) key).startsWith(Property.PROPERTY_RUNTIME_PREFIX)))
			update();
		return ref;
	}

	/**
	   Saves the service properties to the disk.
	 */
	public void saveServiceProperties()
	{
        if( SanityManager.DEBUG)
            SanityManager.ASSERT( storageFactory != null,
                                  "UpdateServiceProperties.saveServiceProperties() called before storageFactory set.");
		try{
			serviceType.saveServiceProperties(serviceName, storageFactory,
					BaseMonitor.removeRuntimeProperties(defaults), false);
		} catch (StandardException mse) {
			throw new PassThroughException(mse);
		}
	}

	/*
	** Class specific methods.
	*/

	private void update() {

		try {
			//look at the comments for serviceBooted at the top to understand this if.
			if (serviceBooted)
				serviceType.saveServiceProperties(serviceName, storageFactory,
					BaseMonitor.removeRuntimeProperties(defaults), true);
		} catch (StandardException mse) {
			throw new PassThroughException(mse);
		}
	}

}