contentadvertisementimpl.java

jxta-cms-src-2.4.zip 是官网上的比较稳定的CMS源代码。目前是最稳定的高版本。

/*
 * 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 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.
 *
 *====================================================================
 *
 * 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.
 *
 * $Id: ContentAdvertisementImpl.java,v 1.18 2006/02/07 20:43:49 bondolo Exp $
 *
 */

package net.jxta.share;

import net.jxta.document.Advertisement;
import net.jxta.document.AdvertisementFactory;
import net.jxta.document.Document;
import net.jxta.document.StructuredDocumentFactory;
import net.jxta.document.StructuredTextDocument;
import net.jxta.document.StructuredDocument;
import net.jxta.document.TextElement;
import net.jxta.document.Element;
import net.jxta.document.MimeMediaType;

import net.jxta.share.metadata.ContentMetadata;
import net.jxta.share.metadata.ContentMetadataFactory;

import java.io.InputStream;
import java.io.IOException;
import java.util.Enumeration;
import java.util.Vector;

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

/*
 * ContentAdvertisement implementation for content manager.
 */
public class ContentAdvertisementImpl extends ContentAdvertisement {

    private final static transient Logger LOG = Logger.getLogger(ContentAdvertisementImpl.class.getName());

    private String name; // content name (required)
    private ContentId cid; // content id (required)
    private long length = -1; // content length (optional)
    private String type; // content type (optional)
    private String description; // content description (optional)
    private ContentMetadata[] metadata;// metadata of content (optional)
    private String address; // address of content (optional)
    private static boolean isRegistered = false;

    private static final String [] fields = {EN_NAME, EN_CID, EN_TYPE};

    public static class Instantiator implements AdvertisementFactory.Instantiator {

        /**
         * Returns the identifying type of this Advertisement.
         *
         * @return String the type of advertisement
         *
         * @since JXTA 1.0
         **/
        public String getAdvertisementType( ) {
            return ContentAdvertisementImpl.getAdvertisementType();
        }

        /**
         * Constructs an instance of <CODE>Advertisement</CODE> matching the type
         * specified by the <CODE>advertisementType</CODE> parameter.
         *
         * @param advertisementType Specifies the mime media type to be associated with the
         * <CODE>StructuredDocument</CODE> to be created.
         * @return The instance of <CODE>Advertisement</CODE> or null if it
         * could not be created.
         *
         * @exception InvocationTargetException error invoking target constructor
         *
         * @since JXTA 1.0
         **/
        public Advertisement newInstance( ) {
            return new ContentAdvertisementImpl();
        }

        /**
         * Constructs an instance of <CODE>Advertisement</CODE> matching the type
         * specified by the <CODE>advertisementType</CODE> parameter.
         *
         * @param root Specifies a portion of a StructuredDocument which will be
         * converted into an Advertisement.
         * @return The instance of <CODE>Advertisement</CODE> or null if it
         * could not be created.
         *
         * @exception InvocationTargetException error invoking target constructor
         *
         * @since JXTA 1.0
         **/
        public Advertisement newInstance( net.jxta.document.Element root ) {
            return new ContentAdvertisementImpl( (TextElement) root );
        }
    };

    // Empty Constructor
    ContentAdvertisementImpl() {
        registerAdvertisement();
    }


    /*
     * Creates a new ContentAdvertisement for the specified content name,
     * id, length, type, and description
     * @param name the content name
     * @param cid the content id
     * @param length the content length, or -1 if not specified
     * @param type the content mime type, or null if not specified
     * @param description the content description, or null if not specified
     * @exception NullPointerException if name or cid is null
     */
    ContentAdvertisementImpl(String name, ContentId cid, long length,
                             String type, String description) {
        registerAdvertisement();

        if (name == null) {
            throw new NullPointerException("name");
        }
        if (cid == null) {
            throw new NullPointerException("cid");
        }
        this.name = name;
        this.cid = cid;
        this.type = type;
        this.length = length;
        this.description = description;
        this.metadata = null;
        this.address = null;
    }

    /*
     * Creates a new ContentAdvertisement for the specified content name,
     * id, length, type, and description
     * @param name the content name
     * @param cid the content id
     * @param length the content length, or -1 if not specified
     * @param type the content mime type, or null if not specified
     * @param description the content description, or null if not specified
     * @param address the address of the peer that contains the content, or
     * null if not specified
     * @exception NullPointerException if name or cid is null
     */
    ContentAdvertisementImpl(String name, ContentId cid, long length,
                             String type, String description, String address) {
        registerAdvertisement();

        if (name == null) {
            throw new NullPointerException("name");
        }
        if (cid == null) {
            throw new NullPointerException("cid");
        }
        this.name = name;
        this.cid = cid;
        this.type = type;
        this.length = length;
        this.description = description;
        this.metadata = null;
        this.address = address;
    }

    /*
     * Creates a new ContentAdvertisement for the specified content name,
     * id, length, type, and description
     * @param name the content name
     * @param cid the content id
     * @param length the content length, or -1 if not specified
     * @param type the content mime type, or null if not specified
     * @param metadata the an array of different metadata descriptions of this
     * content or null if not specified.
     * @param address the address of the peer that contains the content, or
     * null if not specified
     * @exception NullPointerException if name or cid is null or metadata
     * contains a null element.
     */
    ContentAdvertisementImpl(String name, ContentId cid, long length,
                             String type, ContentMetadata[] metadata,
                             String address) {
        registerAdvertisement();

        if (name == null) {
            throw new NullPointerException("name");
        }
        if (cid == null) {
            throw new NullPointerException("cid");
        }
        this.name = name;
        this.cid = cid;
        this.type = type;
        this.length = length;

        //in future versions of this class, description will be completely
        // replaced by metadata, but for now just make it null.
        this.description = null;
        this.metadata = metadata;

        //rat out null metadata elements right away, rather than waiting for
        //appendElements() to be called
        if(metadata != null) {
            for(int a = 0; a < metadata.length; a++) {
                if(metadata[a] == null)
                    throw new NullPointerException("null metadata element");
            }
        }

        this.address = address;
    }

    /**
     * Creates a new ContentAdvertisement from the specified InputStream.