1  /*
     2   * Copyright (c) 2003-2006, Simon Brown
     3   * All rights reserved.
     4   *
     5   * Redistribution and use in source and binary forms, with or without
     6   * modification, are permitted provided that the following conditions are met:
     7   *
     8   *   - Redistributions of source code must retain the above copyright
     9   *     notice, this list of conditions and the following disclaimer.
    10   *
    11   *   - Redistributions in binary form must reproduce the above copyright
    12   *     notice, this list of conditions and the following disclaimer in
    13   *     the documentation and/or other materials provided with the
    14   *     distribution.
    15   *
    16   *   - Neither the name of Pebble nor the names of its contributors may
    17   *     be used to endorse or promote products derived from this software
    18   *     without specific prior written permission.
    19   *
    20   * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS IS"
    21   * AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
    22   * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
    23   * ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR CONTRIBUTORS BE
    24   * LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
    25   * CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
    26   * SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
    27   * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN
    28   * CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE)
    29   * ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE
    30   * POSSIBILITY OF SUCH DAMAGE.
    31   */
    32  package net.sourceforge.pebble.event;
    33  
    34  import net.sourceforge.pebble.api.event.blog.BlogListener;
    35  import net.sourceforge.pebble.api.event.blogentry.BlogEntryListener;
    36  import net.sourceforge.pebble.api.event.comment.CommentListener;
    37  import net.sourceforge.pebble.api.event.trackback.TrackBackListener;
    38  import org.apache.commons.logging.Log;
    39  import org.apache.commons.logging.LogFactory;
    40  
    41  import java.util.ArrayList;
    42  import java.util.List;
    43  
    44  /**
    45   * Maintains a list of listeners, allowing them to be added and removed.
    46   *
    47   * @author Simon Brown
    48   */
    49  public class EventListenerList {
    50  
    51    /** the log in use by this class */
           /* 
    P/P     *  Method: net.sourceforge.pebble.event.EventListenerList__static_init
            * 
            *  Postconditions:
            *    init'ed(log)
            */
    52    private static final Log log = LogFactory.getLog(EventListenerList.class);
    53  
    54    /** the list of blog listeners */
    55    private List blogListeners;
    56  
    57    /** the list of blog entry listeners */
    58    private List blogEntryListeners;
    59  
    60    /** the list of comment listeners */
    61    private List commentListeners;
    62  
    63    /** the list of TrackBack listeners */
    64    private List trackBackListeners;
    65  
    66    /**
    67     * Default, no args constructor.
    68     */
           /* 
    P/P     *  Method: void net.sourceforge.pebble.event.EventListenerList()
            * 
            *  Postconditions:
            *    this.blogEntryListeners == &new ArrayList(EventListenerList#2)
            *    this.blogListeners == &new ArrayList(EventListenerList#1)
            *    this.commentListeners == &new ArrayList(EventListenerList#3)
            *    this.trackBackListeners == &new ArrayList(EventListenerList#4)
            *    new ArrayList(EventListenerList#1) num objects == 1
            *    new ArrayList(EventListenerList#2) num objects == 1
            *    new ArrayList(EventListenerList#3) num objects == 1
            *    new ArrayList(EventListenerList#4) num objects == 1
            */
    69    public EventListenerList() {
    70      this.blogListeners = new ArrayList();
    71      this.blogEntryListeners = new ArrayList();
    72      this.commentListeners = new ArrayList();
    73      this.trackBackListeners = new ArrayList();
    74    }
    75  
    76    /**
    77     * Gets the list of blog listeners.
    78     *
    79     * @return  a List of BlogListener instances
    80     */
    81    public List getBlogListeners() {
             /* 
    P/P       *  Method: List getBlogListeners()
              * 
              *  Preconditions:
              *    init'ed(this.blogListeners)
              * 
              *  Postconditions:
              *    return_value == this.blogListeners
              *    init'ed(return_value)
              */
    82      return this.blogListeners;
    83    }
    84  
    85    /**
    86     * Registers a blog listener.
    87     *
    88     * @param listener    a BlogListener instance
    89     */
    90    public void addBlogListener(BlogListener listener) {
             /* 
    P/P       *  Method: void addBlogListener(BlogListener)
              * 
              *  Preconditions:
              *    this.blogListeners != null
              *    (soft) listener != null
              * 
              *  Presumptions:
              *    java.lang.Object:getClass(...)@93 != null
              *    org.apache.commons.logging.LogFactory:getLog(...)@52 != null
              * 
              *  Test Vectors:
              *    java.util.List:contains(...)@91: {1}, {0}
              */
    91      if (!blogListeners.contains(listener)) {
    92        blogListeners.add(listener);
    93        log.debug(listener.getClass().getName() + " registered");
    94      }
    95    }
    96  
    97    /**
    98     * Unregisters a blog listener.
    99     *
   100     * @param listener    a BlogListener instance
   101     */
   102    public void removeBlogListener(BlogListener listener) {
             /* 
    P/P       *  Method: void removeBlogListener(BlogListener)
              * 
              *  Preconditions:
              *    this.blogListeners != null
              */
   103      blogListeners.remove(listener);
   104    }
   105  
   106    /**
   107     * Gets the list of blog entry listeners.
   108     *
   109     * @return  a List of BlogEntryListener instances
   110     */
   111    public List getBlogEntryListeners() {
             /* 
    P/P       *  Method: List getBlogEntryListeners()
              * 
              *  Preconditions:
              *    init'ed(this.blogEntryListeners)
              * 
              *  Postconditions:
              *    return_value == this.blogEntryListeners
              *    init'ed(return_value)
              */
   112      return this.blogEntryListeners;
   113    }
   114  
   115    /**
   116     * Registers a blog entry listener.
   117     *
   118     * @param listener    a BlogEntryListener instance
   119     */
   120    public void addBlogEntryListener(BlogEntryListener listener) {
             /* 
    P/P       *  Method: void addBlogEntryListener(BlogEntryListener)
              * 
              *  Preconditions:
              *    this.blogEntryListeners != null
              *    (soft) listener != null
              * 
              *  Presumptions:
              *    java.lang.Object:getClass(...)@123 != null
              *    org.apache.commons.logging.LogFactory:getLog(...)@52 != null
              * 
              *  Test Vectors:
              *    java.util.List:contains(...)@121: {1}, {0}
              */
   121      if (!blogEntryListeners.contains(listener)) {
   122        blogEntryListeners.add(listener);
   123        log.debug(listener.getClass().getName() + " registered");
   124      }
   125    }
   126  
   127    /**
   128     * Gets the list of comment listeners.
   129     *
   130     * @return  a List of CommentListener instances
   131     */
   132    public List getCommentListeners() {
             /* 
    P/P       *  Method: List getCommentListeners()
              * 
              *  Preconditions:
              *    init'ed(this.commentListeners)
              * 
              *  Postconditions:
              *    return_value == this.commentListeners
              *    init'ed(return_value)
              */
   133      return this.commentListeners;
   134    }
   135  
   136    /**
   137     * Registers a comment listener.
   138     *
   139     * @param listener    a CommentListener instance
   140     */
   141    public void addCommentListener(CommentListener listener) {
             /* 
    P/P       *  Method: void addCommentListener(CommentListener)
              * 
              *  Preconditions:
              *    this.commentListeners != null
              *    (soft) listener != null
              * 
              *  Presumptions:
              *    java.lang.Object:getClass(...)@144 != null
              *    org.apache.commons.logging.LogFactory:getLog(...)@52 != null
              * 
              *  Test Vectors:
              *    java.util.List:contains(...)@142: {1}, {0}
              */
   142      if (!commentListeners.contains(listener)) {
   143        commentListeners.add(listener);
   144        log.debug(listener.getClass().getName() + " registered");
   145      }
   146    }
   147  
   148    /**
   149     * Gets the list of TrackBack listeners.
   150     *
   151     * @return  a List of TrackBackListener instances
   152     */
   153    public List getTrackBackListeners() {
             /* 
    P/P       *  Method: List getTrackBackListeners()
              * 
              *  Preconditions:
              *    init'ed(this.trackBackListeners)
              * 
              *  Postconditions:
              *    return_value == this.trackBackListeners
              *    init'ed(return_value)
              */
   154      return this.trackBackListeners;
   155    }
   156  
   157    /**
   158     * Registers a TrackBack listener.
   159     *
   160     * @param listener    a TrackBackListener instance
   161     */
   162    public void addTrackBackListener(TrackBackListener listener) {
             /* 
    P/P       *  Method: void addTrackBackListener(TrackBackListener)
              * 
              *  Preconditions:
              *    this.trackBackListeners != null
              *    (soft) listener != null
              * 
              *  Presumptions:
              *    java.lang.Object:getClass(...)@165 != null
              *    org.apache.commons.logging.LogFactory:getLog(...)@52 != null
              * 
              *  Test Vectors:
              *    java.util.List:contains(...)@163: {1}, {0}
              */
   163      if (!trackBackListeners.contains(listener)) {
   164        trackBackListeners.add(listener);
   165        log.debug(listener.getClass().getName() + " registered");
   166      }
   167    }
   168  
   169  
   170  }