asquare.gwt.tk.client.ui.behavior.KeyEventImpl.java Source code

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Here is the source code for asquare.gwt.tk.client.ui.behavior.KeyEventImpl.java

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/*
 * Copyright 2007 Mat Gessel <mat.gessel@gmail.com>
 * 
 * Licensed under the Apache License, Version 2.0 (the "License"); you may not
 * use this file except in compliance with the License. You may obtain a copy of
 * the License at
 * 
 * http://www.apache.org/licenses/LICENSE-2.0
 * 
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
 * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. See the
 * License for the specific language governing permissions and limitations under
 * the License.
 */
package asquare.gwt.tk.client.ui.behavior;

import com.google.gwt.user.client.DOM;
import com.google.gwt.user.client.Event;
import com.google.gwt.user.client.ui.Widget;

public class KeyEventImpl extends InputEventImpl implements KeyEvent {
    private static final long serialVersionUID = 1L;

    protected KeyEventImpl(KeyEventImpl e) {
        super(e);
    }

    /**
     * @param source the widget which is receiving the mouse event
     * @param keyEvent a <code>keydown</code>, <code>keypress</code> or <code>keyup</code> event
     * @param type the DOM event type
     * @param previewPhase <code>true</code> if the event was caught in event preview
     */
    public KeyEventImpl(Widget source, Event keyEvent, int type, boolean previewPhase) {
        super(source, keyEvent, type, previewPhase);
    }

    public static boolean isKeyEvent(Event domEvent) {
        return isKeyEvent(DOM.eventGetType(domEvent));
    }

    public static boolean isKeyEvent(int domEventType) {
        return (domEventType & KEY_EVENTS) != 0;
    }

    /**
     * Gets a code representing a specific keyboard key which was pressed or
     * released. Not valid for keypress events. 
     * 
     * @param event a keydown or keyup event
     * @return a char representing the key pressed
     * @throws IllegalArgumentException if event is other than onkeydown or
     *             onkeyup
     */
    public static int getKeyCode(Event event) {
        if ((DOM.eventGetType(event) & (Event.ONKEYDOWN | Event.ONKEYUP)) == 0)
            throw new IllegalArgumentException();

        return DOM.eventGetKeyCode(event);
    }

    public int getKeyCode() {
        if ((getType() & (Event.ONKEYDOWN | Event.ONKEYUP)) == 0)
            throw new IllegalStateException();

        return DOM.eventGetKeyCode(getDomEvent());
    }

    /**
     * Gets the unicode character from a keypress event. 
     * Returns 0 for keypresses which do not generate characters (i.e. <code>Delete</code>). 
     * 
     * @param event a keypress event
     * @return a unicode character
     * @throws IllegalArgumentException if event is other than onkeypress
     */
    public static char getKeyPressChar(Event event) {
        if (DOM.eventGetType(event) != Event.ONKEYPRESS)
            throw new IllegalArgumentException();

        return (char) DOM.eventGetKeyCode(event);
    }

    public char getKeyPressChar() {
        if (getType() != Event.ONKEYPRESS)
            throw new IllegalStateException();

        return (char) DOM.eventGetKeyCode(getDomEvent());
    }
}