1 /*
   2  * Copyright (c) 1997, 2005, Oracle and/or its affiliates. All rights reserved.
   3  * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
   4  *
   5  * This code is free software; you can redistribute it and/or modify it
   6  * under the terms of the GNU General Public License version 2 only, as
   7  * published by the Free Software Foundation.  Oracle designates this
   8  * particular file as subject to the "Classpath" exception as provided
   9  * by Oracle in the LICENSE file that accompanied this code.
  10  *
  11  * This code is distributed in the hope that it will be useful, but WITHOUT
  12  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  13  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License
  14  * version 2 for more details (a copy is included in the LICENSE file that
  15  * accompanied this code).
  16  *
  17  * You should have received a copy of the GNU General Public License version
  18  * 2 along with this work; if not, write to the Free Software Foundation,
  19  * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA.
  20  *
  21  * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA
  22  * or visit www.oracle.com if you need additional information or have any
  23  * questions.
  24  */
  25 
  26 package sun.awt.im;
  27 
  28 import java.awt.Component;
  29 import java.awt.Rectangle;
  30 import java.awt.im.spi.InputMethod;
  31 
  32 /**
  33  * An input method adapter interfaces with the native input methods
  34  * on a host platform. In general, it looks to the input method
  35  * framework like a Java input method (that may support a few more
  36  * locales than a typical Java input method). However, since it
  37  * often has to work in a slightly hostile environment that's not
  38  * designed for easy integration into the Java input method
  39  * framework, it gets some special treatment that's not available
  40  * to Java input methods.
  41  * <p>
  42  * Licensees are free to modify this class as necessary to implement
  43  * their host input method adapters.
  44  *
  45  * @author JavaSoft International
  46  */
  47 
  48 public abstract class InputMethodAdapter implements InputMethod {
  49 
  50     private Component clientComponent;
  51 
  52     void setClientComponent(Component client) {
  53         clientComponent = client;
  54     }
  55 
  56     protected Component getClientComponent() {
  57         return clientComponent;
  58     }
  59 
  60     protected boolean haveActiveClient() {
  61         return clientComponent != null && clientComponent.getInputMethodRequests() != null;
  62     }
  63 
  64     /**
  65      * Informs the input method adapter about the component that has the AWT
  66      * focus if it's using the input context owning this adapter instance.
  67      */
  68     protected void setAWTFocussedComponent(Component component) {
  69         // ignore - adapters can override if needed
  70     }
  71 
  72     /**
  73      * Returns whether host input methods can support below-the-spot input.
  74      * Returns false by default.
  75      */
  76     protected boolean supportsBelowTheSpot() {
  77         return false;
  78     }
  79 
  80     /**
  81      * Informs the input method adapter not to listen to the native events.
  82      * This method is called when a Java input method is active.
  83      */
  84     protected void stopListening() {
  85         // ignore - adapters can override if needed
  86     }
  87 
  88     /**
  89      * Notifies client Window location or status changes
  90      */
  91     public void notifyClientWindowChange(Rectangle location) {
  92     }
  93 
  94     /**
  95      * Starts reconvertion. An implementing host adapter has to override
  96      * this method if it can support reconvert().
  97      * @exception UnsupportedOperationException when the adapter does not override
  98      * the method.
  99      */
 100     public void reconvert() {
 101         throw new UnsupportedOperationException();
 102     }
 103 
 104     /**
 105      * Disable the native input method. This method is provided for explicitly
 106      * turning off the native IM. The native IM is not turned off
 107      * when the native input method is deactivated. This method is
 108      * always called on AWT EDT. See details in bug 6226489.
 109      */
 110     public abstract void disableInputMethod();
 111 
 112 
 113     /**
 114      * Returns a string with information about the native input method, or
 115      * null.
 116      */
 117     public abstract String getNativeInputMethodInfo();
 118 }