/*
 * Copyright 1997-2005 Sun Microsystems, Inc.  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.  Sun designates this
 * particular file as subject to the "Classpath" exception as provided
 * by Sun 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 Sun Microsystems, Inc., 4150 Network Circle, Santa Clara,
 * CA 95054 USA or visit www.sun.com if you need additional information or
 * have any questions.
 */

package sun.awt.im;

import java.awt.Component;
import java.awt.Rectangle;
import java.awt.im.spi.InputMethod;

/**
 * An input method adapter interfaces with the native input methods
 * on a host platform. In general, it looks to the input method
 * framework like a Java input method (that may support a few more
 * locales than a typical Java input method). However, since it
 * often has to work in a slightly hostile environment that's not
 * designed for easy integration into the Java input method
 * framework, it gets some special treatment that's not available
 * to Java input methods.
 * <p>
 * Licensees are free to modify this class as necessary to implement
 * their host input method adapters.
 *
 * @author JavaSoft International
 */

public abstract class InputMethodAdapter implements InputMethod {

    private Component clientComponent;

    void setClientComponent(Component client) {
        clientComponent = client;
    }

    protected Component getClientComponent() {
        return clientComponent;
    }

    protected boolean haveActiveClient() {
        return clientComponent != null && clientComponent.getInputMethodRequests() != null;
    }

    /**
     * Informs the input method adapter about the component that has the AWT
     * focus if it's using the input context owning this adapter instance.
     */
    protected void setAWTFocussedComponent(Component component) {
        // ignore - adapters can override if needed
    }

    /**
     * Returns whether host input methods can support below-the-spot input.
     * Returns false by default.
     */
    protected boolean supportsBelowTheSpot() {
        return false;
    }

    /**
     * Informs the input method adapter not to listen to the native events.
     * This method is called when a Java input method is active.
     */
    protected void stopListening() {
        // ignore - adapters can override if needed
    }

    /**
     * Notifies client Window location or status changes
     */
    public void notifyClientWindowChange(Rectangle location) {
    }

    /**
     * Starts reconvertion. An implementing host adapter has to override
     * this method if it can support reconvert().
     * @exception UnsupportedOperationException when the adapter does not override
     * the method.
     */
    public void reconvert() {
        throw new UnsupportedOperationException();
    }

    /**
     * Disable the native input method. This method is provided for explicitly
     * turning off the native IM. The native IM is not turned off
     * when the native input method is deactivated. This method is
     * always called on AWT EDT. See details in bug 6226489.
     */
    public abstract void disableInputMethod();


    /**
     * Returns a string with information about the native input method, or
     * null.
     */
    public abstract String getNativeInputMethodInfo();
}