com.day.cq.replication.ReplicationContent Maven / Gradle / Ivy

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 *
 * ADOBE CONFIDENTIAL
 * __________________
 *
 *  Copyright 2011 Adobe Systems Incorporated
 *  All Rights Reserved.
 *
 * NOTICE:  All information contained herein is, and remains
 * the property of Adobe Systems Incorporated and its suppliers,
 * if any.  The intellectual and technical concepts contained
 * herein are proprietary to Adobe Systems Incorporated and its
 * suppliers and are protected by trade secret or copyright law.
 * Dissemination of this information or reproduction of this material
 * is strictly forbidden unless prior written permission is obtained
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 **************************************************************************/

package com.day.cq.replication;

import java.io.IOException;
import java.io.InputStream;
import java.util.Collection;
import java.util.Collections;

/**
 * This interface describes the assembled content to replicate.
 */
public interface ReplicationContent {

    /**
     * Implements a void replication content to be used for delete or flush
     * actions.
     */
    ReplicationContent VOID = new ReplicationContent() {

        /**
         * {@inheritDoc}
         *
         * @return null
         */
        public InputStream getInputStream() throws IOException {
            return null;
        }

        /**
         * {@inheritDoc}
         *
         * @return null
         */
        public String getContentType() {
            return null;
        }

        /**
         * {@inheritDoc}
         *
         * @return -1
         */
        public long getLastModified() {
            return -1;
        }

        /**
         * {@inheritDoc}
         *
         * @return 0
         */
        public long getContentLength() {
            return 0;
        }

        /**
         * {@inheritDoc}
         *
         * Does nothing.
         */
        public void acquire(String agentName) {
        }

        /**
         * {@inheritDoc}
         *
         * Does nothing.
         */
        public void release(String agentName) {
        }

        /**
         * {@inheritDoc}
         *
         * @return an empty collection
         */
        public Collection getAcquiredBy() {
            return Collections.emptySet();
        }

        /**
         * {@inheritDoc}
         *
         * does nothing
         */
        public void destroy() {
        }

        /**
         * {@inheritDoc}
         * 
         * @return null
         */
        public ReplicationContentFacade getFacade() {
            return null;
        }

        /**
         * Returns "ReplicationContent.VOID"
         * @return "ReplicationContent.VOID"
         */
        @Override
        public String toString() {
            return "ReplicationContent.VOID";
        }
    };

    /**
     * Get the input stream for the content.
     * @return return the input stream for this content or null if the underlying data source does not
     *         exist anymore.
     *
     * @throws IOException if an I/O error occurrs
     */
    InputStream getInputStream() throws IOException;

    /**
     * Get the content type
     * @return The content type or null.
     */
    String getContentType();

    /**
     * Return the content length if known
     * @return Return the content length or -1 if the length is unknown.
     */
    long getContentLength();

    /**
     * Returns the last modified time or -1 if unknown
     * @return the last modified time
     */
    long getLastModified();

    /**
     * Marks this content to be used by the given agent.
     *
     * @param agentName name of the agent
     */
    void acquire(String agentName);

    /**
     * Unmarks this content for be used by the given agent.
     *
     * @param agentName The name of the agent.
     */
    void release(String agentName);

    /**
     * Returns the collection of agent names that use this content.
     *
     * @return the names
     */
    Collection getAcquiredBy();

    /**
     * Destroy the cached content.
     * This destroys the cached content regardless of the current
     * value of the usage counter.
     */
    void destroy();

    /**
     * Returns the facade for this content.
     * @return the facade
     */
    ReplicationContentFacade getFacade();

}