src/java.desktop/share/classes/javax/swing/AbstractListModel.java

*** 1,7 ****
  /*
!  * Copyright (c) 1997, 2015, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
--- 1,7 ----
  /*
!  * Copyright (c) 1997, 2018, Oracle and/or its affiliates. All rights reserved.
   * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   *
   * This code is free software; you can redistribute it and/or modify it
   * under the terms of the GNU General Public License version 2 only, as
   * published by the Free Software Foundation.  Oracle designates this
*** 23,34 ****
   * questions.
   */
  
  package javax.swing;
  
! import javax.swing.event.*;
  import java.io.Serializable;
  import java.util.EventListener;
  
  /**
   * The abstract definition for the data model that provides
   * a <code>List</code> with its contents.
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   * questions.
   */
  
  package javax.swing;
  
! import javax.swing.event.EventListenerList;
! import javax.swing.event.ListDataListener;
! import javax.swing.event.ListDataEvent;
  import java.io.Serializable;
+ import java.util.function.BiConsumer;
  import java.util.EventListener;
  
  /**
   * The abstract definition for the data model that provides
   * a <code>List</code> with its contents.
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--- 98,129 ----
          return listenerList.getListeners(ListDataListener.class);
      }
  
  
      /**
+      * The workhorse function which does the job of calling the listeners
+      * interested in listening to the appropriate event that has occurred.
+      * Functions fireContentsChanged, fireIntervalAdded and fireIntervalRemoved
+      * call this function with appropriate arguments filled.
+      */
+     private void fireUpdates(Object source, int index0, int index1, int eventType, 
+                             BiConsumer<ListDataListener, ListDataEvent> func) {
+         Object[] listeners = listenerList.getListenerList();
+         ListDataEvent e = null;
+ 
+         for (int i = listeners.length - 2; i >= 0; i -= 2) {
+             if (listeners[i] == ListDataListener.class) {
+                 if (e == null) {
+                     e = new ListDataEvent(source, eventType, index0, index1);
+                 }
+                 func.accept((ListDataListener)listeners[i+1], e);
+             }
+         }
+     }
+ 
+ 
+     /**
       * <code>AbstractListModel</code> subclasses must call this method
       * <b>after</b>
       * one or more elements of the list change.  The changed elements
       * are specified by the closed interval index0, index1 -- the endpoints
       * are included.  Note that
*** 110,130 ****
       * @see EventListenerList
       * @see DefaultListModel
       */
      protected void fireContentsChanged(Object source, int index0, int index1)
      {
!         Object[] listeners = listenerList.getListenerList();
!         ListDataEvent e = null;
! 
!         for (int i = listeners.length - 2; i >= 0; i -= 2) {
!             if (listeners[i] == ListDataListener.class) {
!                 if (e == null) {
!                     e = new ListDataEvent(source, ListDataEvent.CONTENTS_CHANGED, index0, index1);
!                 }
!                 ((ListDataListener)listeners[i+1]).contentsChanged(e);
!             }
!         }
      }
  
  
      /**
       * <code>AbstractListModel</code> subclasses must call this method
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       * @see EventListenerList
       * @see DefaultListModel
       */
      protected void fireContentsChanged(Object source, int index0, int index1)
      {
!         fireUpdates(source, index0, index1, ListDataEvent.CONTENTS_CHANGED, 
!                 (l, e) -> l.contentsChanged(e));
      }
  
  
      /**
       * <code>AbstractListModel</code> subclasses must call this method
*** 140,160 ****
       * @see EventListenerList
       * @see DefaultListModel
       */
      protected void fireIntervalAdded(Object source, int index0, int index1)
      {
!         Object[] listeners = listenerList.getListenerList();
!         ListDataEvent e = null;
! 
!         for (int i = listeners.length - 2; i >= 0; i -= 2) {
!             if (listeners[i] == ListDataListener.class) {
!                 if (e == null) {
!                     e = new ListDataEvent(source, ListDataEvent.INTERVAL_ADDED, index0, index1);
!                 }
!                 ((ListDataListener)listeners[i+1]).intervalAdded(e);
!             }
!         }
      }
  
  
      /**
       * <code>AbstractListModel</code> subclasses must call this method
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       * @see EventListenerList
       * @see DefaultListModel
       */
      protected void fireIntervalAdded(Object source, int index0, int index1)
      {
!         fireUpdates(source, index0, index1, ListDataEvent.INTERVAL_ADDED,
!             (l, e) -> l.intervalAdded(e));
      }
  
  
      /**
       * <code>AbstractListModel</code> subclasses must call this method
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       * @see EventListenerList
       * @see DefaultListModel
       */
      protected void fireIntervalRemoved(Object source, int index0, int index1)
      {
!         Object[] listeners = listenerList.getListenerList();
!         ListDataEvent e = null;
! 
!         for (int i = listeners.length - 2; i >= 0; i -= 2) {
!             if (listeners[i] == ListDataListener.class) {
!                 if (e == null) {
!                     e = new ListDataEvent(source, ListDataEvent.INTERVAL_REMOVED, index0, index1);
!                 }
!                 ((ListDataListener)listeners[i+1]).intervalRemoved(e);
!             }
!         }
      }
  
      /**
       * Returns an array of all the objects currently registered as
       * <code><em>Foo</em>Listener</code>s
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       * @see EventListenerList
       * @see DefaultListModel
       */
      protected void fireIntervalRemoved(Object source, int index0, int index1)
      {
!         fireUpdates(source, index0, index1, ListDataEvent.INTERVAL_REMOVED,
!             (l, e) -> l.intervalRemoved(e));
      }
  
      /**
       * Returns an array of all the objects currently registered as
       * <code><em>Foo</em>Listener</code>s