/* ====================================================================
* Loom Software License, version 1.1
*
* Copyright (c) 2003, Loom Group. All rights reserved.
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. Neither the name of the Loom Group nor the name "Loom" nor
* the names of its contributors may be used to endorse or promote
* products derived from this software without specific prior
* written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
* FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
* COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
* BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES;
* LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER
* CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN
* ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
* POSSIBILITY OF SUCH DAMAGE.
*
* ====================================================================
*
* Loom includes code from the Apache Software Foundation
*
* ====================================================================
* The Apache Software License, Version 1.1
*
* Copyright (c) 1997-2003 The Apache Software Foundation. All rights
* reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
*
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in
* the documentation and/or other materials provided with the
* distribution.
*
* 3. The end-user documentation included with the redistribution,
* if any, must include the following acknowledgment:
* "This product includes software developed by the
* Apache Software Foundation (http://www.apache.org/)."
* Alternately, this acknowledgment may appear in the software
* itself, if and wherever such third-party acknowledgments
* normally appear.
*
* 4. The names "Jakarta", "Avalon", and "Apache Software Foundation"
* must not be used to endorse or promote products derived from this
* software without prior written permission. For written
* permission, please contact apache@apache.org.
*
* 5. Products derived from this software may not be called "Apache",
* nor may "Apache" appear in their name, without prior written
* permission of the Apache Software Foundation.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESSED OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE APACHE SOFTWARE FOUNDATION OR
* ITS CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
* LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF
* USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND
* ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
* OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
* OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
* SUCH DAMAGE.
*/
package org.codehaus.loom.components.manager;
import java.util.HashMap;
import org.codehaus.loom.interfaces.LoomException;
import org.codehaus.loom.interfaces.SystemManager;
import org.codehaus.spice.salt.i18n.ResourceManager;
import org.codehaus.spice.salt.i18n.Resources;
/**
* Implements a management context local to a particular process with which it
* can register its managed object. The naming scheme that results is meant to
* be compatible with jmx.
*
* @author <a href="mailto:huw@apache.org">Huw Roberts</a>
*/
class SubContext
implements SystemManager
{
private static final Resources REZ =
ResourceManager.getPackageResources( SubContext.class );
private static final String EMPTY_STRING = "";
private final HashMap m_subcontexts = new HashMap();
private final SystemManager m_parent;
private final String m_name;
private final String m_type;
/**
* Creates new SubContext to the specified context. Objects registered
* under the subcontext will be typed with the name of the context so the
* jmx name becomes 'contextName' + 'objectNameSoFar'
*
* @param parent the parent context
* @param name the subcontext name
*/
public SubContext( final SystemManager parent,
final String name,
final String type )
{
if( null == parent )
{
throw new NullPointerException( "parent" );
}
m_parent = parent;
m_name = name;
m_type = type;
}
/**
* Register an object for management. The object is exported through some
* management scheme (typically JMX). Note that the particular management
* scheme will most likely use reflection to extract manageable
* information.
*
* @param name the name to register object under
* @param object the object
* @throws LoomException if an error occurs such as name already
* registered.
* @throws IllegalArgumentException if object is null
*/
public void register( final String name, final Object object )
throws LoomException, IllegalArgumentException
{
m_parent.register( jmxName( name ), object );
}
/**
* Unregister named object.
*
* @param name the name of object to unregister
* @throws LoomException if an error occurs such as when no such object
* registered.
*/
public void unregister( final String name )
throws LoomException
{
m_parent.unregister( jmxName( name ) );
}
/**
* Returns the subcontext of the specified name. If it does not exist it is
* created.
*
* @return the subcontext with the specified name
* @throws LoomException if context cannot be created or retrieved
*/
public SystemManager getSubContext( final String name,
final String type )
throws LoomException
{
if( null == type || EMPTY_STRING.equals( type ) )
{
final String message =
REZ.getString( "subcontext.error.no.subcontext" );
throw new LoomException( message );
}
else if( null != name && this.m_type == null )
{
final String message =
REZ.getString( "subcontext.error.no.subcontext" );
throw new LoomException( message );
}
// get from list if possible
final String key = contextKey( name, type );
SystemManager subcontext =
(SystemManager)m_subcontexts.get( key );
// otherwise create and add to list
if( subcontext == null )
{
subcontext = new SubContext( this, name, type );
m_subcontexts.put( key, subcontext );
}
return subcontext;
}
/**
* Helper method used to generate the jmx name by appending the current name
* and passing up the chain to the root context
*/
private String jmxName( final String name )
{
final StringBuffer sb = new StringBuffer();
if( null != m_name )
{
sb.append( m_name );
sb.append( ',' );
}
if( null != m_type )
{
sb.append( m_type );
sb.append( '=' );
}
sb.append( name );
return sb.toString();
}
/**
* Helper method to get key used to store subcontexts in m_subcontexts
*/
private String contextKey( final String parent,
final String type )
{
return parent + "|" + type;
}
}