001    /*
002     * Copyright 2006 Mat Gessel <mat.gessel@gmail.com>
003     * 
004     * Licensed under the Apache License, Version 2.0 (the "License"); you may not
005     * use this file except in compliance with the License. You may obtain a copy of
006     * the License at
007     * 
008     * http://www.apache.org/licenses/LICENSE-2.0
009     * 
010     * Unless required by applicable law or agreed to in writing, software
011     * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
012     * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
013     * License for the specific language governing permissions and limitations under
014     * the License.
015     */
016    package asquare.gwt.tk.client.util;
017    
018    import java.util.HashMap;
019    
020    import com.google.gwt.user.client.Command;
021    
022    /**
023     * A map that facilitates looking up which command is associated to a hot key.
024     * Supports (char, Command) pairs. Similar to the Swing
025     * {@link javax.swing.ActionMap ActionMap}.
026     */
027    public class KeyMap extends HashMap
028    {
029            /**
030             * Create a mapping between a hot key and a command. To ensure case
031             * consistency across keypress and keydown/keyup events you can convert hot
032             * key characters to upper-case before creating the mapping.
033             * 
034             * @param keyCode a keyboard shortcut
035             * @param command a Command to associate with the hot key
036             */
037            public void put(char keyCode, Command command)
038            {
039                    put(new Character(keyCode), command);
040            }
041    
042            /**
043             * Determines if the map contains a mapping for the specified hot key.
044             * 
045             * @param keyCode a keyboard shortcut
046             * @return <code>true</code> if a mapping exists for <code>keyCode</code>
047             */
048            public boolean containsKey(char keyCode)
049            {
050                    return containsKey(new Character(keyCode));
051            }
052    
053            /**
054             * Get the command to which the specified hot key is mapped.
055             * 
056             * @param keyCode a keyboard shortcut
057             * @return a Command or <code>null</code>
058             */
059            public Command get(char keyCode)
060            {
061                    return (Command) get(new Character(keyCode));
062            }
063            
064            /**
065             * Remove a mapping for the specified hot key. Returns the previously mapped
066             * command, if applicable.
067             * 
068             * @param keyCode a keyboard shortcut
069             * @return a Command or <code>null</code>
070             */
071            public Command remove(char keyCode)
072            {
073                    return (Command) remove(new Character(keyCode));
074            }
075    }