endpointaddress.java

jxta_src_2.41b jxta 2.41b 最新版源码 from www.jxta.org

/*
 *
 * $Id: EndpointAddress.java,v 1.29 2005/11/16 23:42:02 bondolo Exp $
 *
 * Copyright (c) 2001 Sun Microsystems, Inc.  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
 *       Sun Microsystems, Inc. for Project JXTA."
 *    Alternately, this acknowledgment may appear in the software itself,
 *    if and wherever such third-party acknowledgments normally appear.
 *
 * 4. The names "Sun", "Sun Microsystems, Inc.", "JXTA" and "Project JXTA"
 *    must not be used to endorse or promote products derived from this
 *    software without prior written permission. For written
 *    permission, please contact Project JXTA at http://www.jxta.org.
 *
 * 5. Products derived from this software may not be called "JXTA",
 *    nor may "JXTA" appear in their name, without prior written
 *    permission of Sun.
 *
 * 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 SUN MICROSYSTEMS 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.
 *
 * ====================================================================
 *
 * This software consists of voluntary contributions made by many
 * individuals on behalf of Project JXTA.  For more
 * information on Project JXTA, please see
 * <http://www.jxta.org/>.
 *
 * This license is based on the BSD license adopted by the Apache Foundation.
 */

package net.jxta.endpoint;

import java.lang.ref.SoftReference;
import java.net.URI;

import java.io.UnsupportedEncodingException;

import org.apache.log4j.Level;
import org.apache.log4j.Logger;

import net.jxta.id.ID;

/**
 * Describes a destination to which JXTA messages may be sent. This may be:
 *
 *  <ul>
 *      <li>A Pipe</li>
 *      <li>A Peergroup (propagate)</li>
 *      <li>A Peer</li>
 *      <li>A Message Transport for a Peer</li>
 *  </ul>
 *
 *  <p/>An Endpoint Address is composed of four components: a protocol (also
 *  called a scheme), a protocol address (also called an authority), an optional
 * service name and optional service parameter.
 *
 *  <p/><b>The Protocol</b><ul>
 *      <li>Describes the method of addressing used by the remainder of the
 *      endpoint address.</li>
 *      <li>Indicates how the address will be resolved, ie. who will resolve it.</li>
 *      <li>Cooresponds to the "scheme" portion of a URI in W3C palance.
 *      <li><b>May not</b> contain the ":" character.
 *  </ul>
 *
 *  <p/><b>The Protocol Address</b><ul>
 *      <li>Describes the destination entity of this address.</li>
 *      <li>Form is dependant upon the protocol being used.</li>
 *      <li>Cooresponds to the "Authority" portion of a URI in W3C palance.
 *      <li><b>May not</b> contain the "/" character.
 *  </ul>
 *
 *  <p/><b>The Service Name</b> (optional)<ul>
 *      <li>Describes the service that is the destination. A service cannot be
 *      a protocol address because a service must have a location; a group or a
 *      specific peer.</li>
 *      <li>Form is dependant upon service intent. This is matched as a UTF-8
 *      string.</li>
 *      <li><b>May not</b> contain the "/" character.
 *  </ul>
 *
 *  <p/><b>The Service Parameter</b> (optional)<ul>
 *      <li>Describes parameters for the service.</li>
 *      <li>Form is dependant upon service intent. This is matched as a UTF-8
 *      string (if it is used for matching).</li>
 *  </ul>
 *
 * @see  net.jxta.endpoint.EndpointService
 * @see  net.jxta.endpoint.MessageTransport
 * @see  net.jxta.endpoint.Messenger
 * @see  net.jxta.pipe.PipeService
 *
 **/
public class EndpointAddress {
    
    /**
     *  Log4J Logger
     **/
    private static final Logger LOG = Logger.getLogger(EndpointAddress.class.getName());
    
    /**
     *  if true then the address is a url, otherwise its a uri (likely a urn).
     **/
    private boolean hierarchical = true;
    
    /**
     *  Describes the method of addressing used by the remainder of the
     *  endpoint address.
     **/
    private String protocol = null;
    
    /**
     *  Describes the destination entity of this address.
     **/
    private String protocolAddress = null;
    
    /**
     *  Describes the service that is the destination.
     **/
    private String service = null;
    
    /**
     *  Describes parameters for the service.
     **/
    private String serviceParam = null;
    
    /**
     *  number of modifications since initial creation. used in caching of
     *  string representation and hashCode.
     **/
    private transient volatile int modcount = 0;
    
    /**
     *  mod count at last hash code calc
     **/
    private transient int modAtLastHashCalc = -1;
    
    /**
     *  cached calculated hash code.
     **/
    private transient int cachedHashCode = 0;
    
    /**
     *  mod count at last string representation creation.
     **/
    private transient int modAtLastStringCalc = -1;
    
    /**
     *  cached copy of string representation.
     **/
    private transient SoftReference cachedToString = null;
    
    /**
     *  Returns an unmodifiable copy of the specified EndpointAddress. This
     *  method allows modules to provide users with "read-only" access to
     *  an endpoint address without needing to make a clone for each copy
     *  returned. Attempts to modify the returned EndpointAddress results
     * in an {@link java.lang.UnsupportedOperationException}.
     **/
    private static class UnmodifiableEndpointAddress extends EndpointAddress {
        
        /**
         *  Create a new unmodifiable endpoint address.
         **/
        public UnmodifiableEndpointAddress( EndpointAddress address ) {
            super();
            super.setProtocolName( address.getProtocolName() );
            super.setProtocolAddress( address.getProtocolAddress() );
            super.setServiceName( address.getServiceName() );
            super.setServiceParameter( address.getServiceParameter() );
        }
        
        /**
         *  {@inheritDoc}
         *
         *  <p/>throws an {@link java.lang.UnsupportedOperationException} for every operation.
         **/
        public void setProtocolName(String name) {
            throw new UnsupportedOperationException( "This EndpointAddress is not modifiable" );
        }
        
        /**
         *  {@inheritDoc}
         *
         *  <p/>throws an {@link java.lang.UnsupportedOperationException} for every operation.
         **/
        public void setProtocolAddress(String address) {
            throw new UnsupportedOperationException( "This EndpointAddress is not modifiable" );
        }
        
        /**
         *  {@inheritDoc}
         *
         *  <p/>throws an {@link java.lang.UnsupportedOperationException} for every operation.
         **/
        public void setServiceName(String name) {
            throw new UnsupportedOperationException( "This EndpointAddress is not modifiable" );
        }
        
        /**
         *  {@inheritDoc}
         *
         *  <p/>throws an {@link java.lang.UnsupportedOperationException} for every operation.
         **/
        public void setServiceParameter(String param) {
            throw new UnsupportedOperationException( "This EndpointAddress is not modifiable" );
        }
    }
    
    /**
     *  Returns an unmodifiable clone of the provided EndpointAddress.
     *
     *  @param address  the address to be cloned.
     *  @return the unmodifiable address clone.
     **/
    public static EndpointAddress unmodifiableEndpointAddress( EndpointAddress address ) {
        return new EndpointAddress.UnmodifiableEndpointAddress( address );
    }
    
    /**
     * Builds an empty (invalid) Endpoint Address.
     *
     *  @deprecated EndpointAddress works better if it is immutable.
     **/
    public EndpointAddress() {
    }
    
    /**
     * Builds an Address from a string
     *
     *  @param address the string representation of the address.
     */
    public EndpointAddress(String address) {
        if( address == null ) {
            throw new IllegalArgumentException( "address must not be null" );
        }
        
        parseURI(address);
    }
    
    /**
     *  Create an EndpointAddress whose value is initialized from the provided
     *  URI.
     *
     *  @param address the URI representation of the address.
     */
    public EndpointAddress( URI address ) {
        this( address.toString() );
    }

    /**
     * Constructor which builds an address from a byte array containing a UTF-8
     * string.
     *
     *  @deprecated There isn't really ever a good reason to use this since it
     *  has to assume the character encoding.
     *
     * @param bytes byte array containing a UTF-8 string of the endpoint address to be constructed.
     **/
    public EndpointAddress(byte[] bytes) {
        if( bytes == null ) {
            throw new IllegalArgumentException( "bytes must not be null" );
        }
        
        try {
            parseURI(new String(bytes, "UTF8"));
        } catch(UnsupportedEncodingException ex) {
            throw new UnsupportedOperationException(ex.toString());
        }
    }
    
    /**
     * Constructor which builds an endpoint address from a base address and
     * replacement service and params
     *
     * @param base The EndpointAddress on which the new EndpointAddress will be based
     * @param service provides an alternate service for the new EndpointAddress.
     * @param serviceParam provides and alternate service parameter for the new EndpointAddress
     */
    public EndpointAddress( EndpointAddress base, String service, String serviceParam ) {
        if( base == null ) {
            throw new IllegalArgumentException( "base EndpointAddress must not be null" );
        }
        
        setProtocolName( base.getProtocolName() );
        setProtocolAddress( base.getProtocolAddress() );
        setServiceName( service );
        setServiceParameter( serviceParam );
    }
    
    /**
     * Constructor which builds an address the four standard constituent parts.
     *
     * @param address Describes the destination entity of this address.
     * @param protocol Describes the method of addressing used by the remainder of the
     *  endpoint address.
     * @param service String containing the name of the destination service
     * @param serviceParam String containing the service parameter
     **/
    public EndpointAddress( String protocol, String address, String service, String serviceParam ) {
        if( protocol == null ) {
            throw new IllegalArgumentException( "protocol must not be null" );
        }
        
        if( address == null ) {
            throw new IllegalArgumentException( "address must not be null" );
        }
        
        setProtocolName( protocol );
        setProtocolAddress( address );
        setServiceName( service );
        setServiceParameter( serviceParam );
    }
    
    /**
     * Constructor which builds an address from a standard jxta id and a
     * service and param.
     *
     * @param id the ID which will be the destination of the endpoint address
     * @param service String containing the name of the destination service
     * @param serviceParam String containing the service parameter
     **/
    public EndpointAddress( ID id, String service, String serviceParam ) {
        if( null == id ) {
            throw new IllegalArgumentException( "id must not be null" );
        }
        
        setProtocolName( ID.URIEncodingName + ":" + ID.URNNamespace );
        setProtocolAddress( id.getUniqueValue().toString() );
        setServiceName( service );
        setServiceParameter( serviceParam );
    }
    
    /**
     *  {@inheritDoc}
     **/
    public Object clone( ) {
        EndpointAddress clone = new EndpointAddress( getProtocolName(),
            getProtocolAddress(),
            getServiceName(),
            getServiceParameter() );
        
        return clone;
    }
    
    /**
     *  {@inheritDoc}
     **/
    public boolean equals( Object target ) {
        if( this == target ) {
            return true;
        }
        
        if (target instanceof EndpointAddress ) {
            EndpointAddress likeMe = (EndpointAddress) target;
            
            boolean result;
            
            if( (null == protocol) || (null == protocolAddress) ) {
                throw new IllegalStateException( "Corrupt EndpointAddress, protocol or address is null" );
            }
            
            result = (hierarchical == likeMe.hierarchical) &&
            protocol.equalsIgnoreCase(likeMe.protocol) &&