| /* |
| * Copyright (c) 2005, 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 |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.java.accessibility.util; |
| |
| import java.util.*; |
| import java.beans.*; |
| import java.awt.*; |
| import java.awt.event.*; |
| import javax.accessibility.*; |
| |
| /** |
| * <P>The {@code AccessibilityListenerList} is a copy of the Swing |
| * {@link javax.swing.event.EventListenerList EventListerList} class. |
| * |
| */ |
| |
| @jdk.Exported |
| public class AccessibilityListenerList { |
| /* A null array to be shared by all empty listener lists */ |
| private final static Object[] NULL_ARRAY = new Object[0]; |
| |
| /** |
| * The list of listener type, listener pairs |
| */ |
| protected transient Object[] listenerList = NULL_ARRAY; |
| |
| /** |
| * Passes back the event listener list as an array of listener type, listener pairs. |
| * Note that for performance reasons, this implementation passes back the actual |
| * data structure in which the listener data is stored internally. This method |
| * is guaranteed to pass back a non-null array, so that no null-checking |
| * is required in fire methods. A zero-length array of Object is returned if |
| * there are currently no listeners. |
| * <p> |
| * Absolutely no modification of the data contained in this array should be |
| * made. If any such manipulation is necessary, it should be done on a copy |
| * of the array returned rather than the array itself. |
| * |
| * @return an array of listener type, listener pairs. |
| */ |
| public Object[] getListenerList() { |
| return listenerList; |
| } |
| |
| /** |
| * Returns the total number of listeners for this listener list. |
| * |
| * @return the total number of listeners for this listener list. |
| */ |
| public int getListenerCount() { |
| return listenerList.length/2; |
| } |
| |
| /** |
| * Return the total number of listeners of the supplied type |
| * for this listener list. |
| * |
| * @param t the type of the listener to be counted |
| * @return the number of listeners found |
| */ |
| public int getListenerCount(Class t) { |
| int count = 0; |
| Object[] lList = listenerList; |
| for (int i = 0; i < lList.length; i+=2) { |
| if (t == (Class)lList[i]) |
| count++; |
| } |
| return count; |
| } |
| |
| /** |
| * Add the listener as a listener of the specified type. |
| * |
| * @param t the type of the listener to be added |
| * @param l the listener to be added |
| */ |
| public synchronized void add(Class t, EventListener l) { |
| if (!t.isInstance(l)) { |
| throw new IllegalArgumentException("Listener " + l + |
| " is not of type " + t); |
| } |
| if (l ==null) { |
| throw new IllegalArgumentException("Listener " + l + |
| " is null"); |
| } |
| if (listenerList == NULL_ARRAY) { |
| // if this is the first listener added, |
| // initialize the lists |
| listenerList = new Object[] { t, l }; |
| } else { |
| // Otherwise copy the array and add the new listener |
| int i = listenerList.length; |
| Object[] tmp = new Object[i+2]; |
| System.arraycopy(listenerList, 0, tmp, 0, i); |
| |
| tmp[i] = t; |
| tmp[i+1] = l; |
| |
| listenerList = tmp; |
| } |
| } |
| |
| /** |
| * Remove the listener as a listener of the specified type. |
| * |
| * @param t the type of the listener to be removed |
| * @param l the listener to be removed |
| */ |
| public synchronized void remove(Class t, EventListener l) { |
| if (!t.isInstance(l)) { |
| throw new IllegalArgumentException("Listener " + l + |
| " is not of type " + t); |
| } |
| if (l ==null) { |
| throw new IllegalArgumentException("Listener " + l + |
| " is null"); |
| } |
| |
| // Is l on the list? |
| int index = -1; |
| for (int i = listenerList.length-2; i>=0; i-=2) { |
| if ((listenerList[i]==t) && (listenerList[i+1] == l)) { |
| index = i; |
| break; |
| } |
| } |
| |
| // If so, remove it |
| if (index != -1) { |
| Object[] tmp = new Object[listenerList.length-2]; |
| // Copy the list up to index |
| System.arraycopy(listenerList, 0, tmp, 0, index); |
| // Copy from two past the index, up to |
| // the end of tmp (which is two elements |
| // shorter than the old list) |
| if (index < tmp.length) |
| System.arraycopy(listenerList, index+2, tmp, index, |
| tmp.length - index); |
| // set the listener array to the new array or null |
| listenerList = (tmp.length == 0) ? NULL_ARRAY : tmp; |
| } |
| } |
| |
| /** |
| * Return a string representation of the {@code AccessibilityListenerList}. |
| * |
| * @return a string representation of the {@code AccessibilityListenerList}. |
| */ |
| public String toString() { |
| Object[] lList = listenerList; |
| String s = "EventListenerList: "; |
| s += lList.length/2 + " listeners: "; |
| for (int i = 0 ; i <= lList.length-2 ; i+=2) { |
| s += " type " + ((Class)lList[i]).getName(); |
| s += " listener " + lList[i+1]; |
| } |
| return s; |
| } |
| } |