1 /*
   2  * Copyright (c) 2011, 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 
  27 package sun.lwawt;
  28 
  29 import java.awt.Dimension;
  30 import java.awt.FontMetrics;
  31 import java.awt.Insets;
  32 import java.awt.SystemColor;
  33 import java.awt.TextComponent;
  34 import java.awt.event.TextEvent;
  35 import java.awt.event.InputMethodListener;
  36 import java.awt.event.InputMethodEvent;
  37 import java.awt.im.InputMethodRequests;
  38 import java.awt.peer.TextComponentPeer;
  39 import sun.awt.AWTAccessor;
  40 
  41 import javax.swing.JComponent;
  42 import javax.swing.event.DocumentEvent;
  43 import javax.swing.event.DocumentListener;
  44 import javax.swing.text.Document;
  45 import javax.swing.text.JTextComponent;
  46 
  47 abstract class LWTextComponentPeer<T extends TextComponent, D extends JComponent>
  48         extends LWComponentPeer<T, D>
  49         implements DocumentListener, TextComponentPeer, InputMethodListener {
  50 
  51     /**
  52      * Character with reasonable value between the minimum width and maximum.
  53      */
  54     protected static final char WIDE_CHAR = 'w';
  55     private volatile boolean firstChangeSkipped;
  56 
  57     LWTextComponentPeer(final T target,
  58                         final PlatformComponent platformComponent) {
  59         super(target, platformComponent);
  60         if (!getTarget().isBackgroundSet()) {
  61             getTarget().setBackground(SystemColor.text);
  62         }
  63     }
  64 
  65     @Override
  66     void initializeImpl() {
  67         super.initializeImpl();
  68         synchronized (getDelegateLock()) {
  69             // This listener should be added before setText().
  70             getTextComponent().getDocument().addDocumentListener(this);
  71         }
  72         setEditable(getTarget().isEditable());
  73         setText(getTarget().getText());
  74         getTarget().addInputMethodListener(this);
  75         final int start = getTarget().getSelectionStart();
  76         final int end = getTarget().getSelectionEnd();
  77         if (end > start) {
  78             select(start, end);
  79         }
  80         setCaretPosition(getTarget().getCaretPosition());
  81         firstChangeSkipped = true;
  82     }
  83 
  84     @Override
  85     protected final void disposeImpl() {
  86         synchronized (getDelegateLock()) {
  87             // visible caret has a timer thread which must be stopped
  88             getTextComponent().getCaret().setVisible(false);
  89         }
  90         super.disposeImpl();
  91     }
  92 
  93     /**
  94      * This method should be called under getDelegateLock().
  95      */
  96     abstract JTextComponent getTextComponent();
  97 
  98     public Dimension getPreferredSize(final int rows, final int columns) {
  99         final Insets insets;
 100         synchronized (getDelegateLock()) {
 101             insets = getDelegate().getInsets();
 102         }
 103         final int borderHeight = insets.top + insets.bottom;
 104         final int borderWidth = insets.left + insets.right;
 105         final FontMetrics fm = getFontMetrics(getFont());
 106         final int charWidth = (fm != null) ? fm.charWidth(WIDE_CHAR) : 10;
 107         final int itemHeight = (fm != null) ? fm.getHeight() : 10;
 108         return new Dimension(columns * charWidth + borderWidth,
 109                              rows * itemHeight + borderHeight);
 110     }
 111 
 112     @Override
 113     public final void setEditable(final boolean editable) {
 114         synchronized (getDelegateLock()) {
 115             getTextComponent().setEditable(editable);
 116         }
 117     }
 118 
 119     @Override
 120     public final String getText() {
 121         synchronized (getDelegateLock()) {
 122             return getTextComponent().getText();
 123         }
 124     }
 125 
 126     @Override
 127     public void setText(final String l) {
 128         synchronized (getDelegateLock()) {
 129             // Please note that we do not want to post an event
 130             // if TextArea.setText() or TextField.setText() replaces an empty text by an empty text,
 131             // that is, if component's text remains unchanged.
 132             if (l.isEmpty() && getTextComponent().getDocument().getLength() == 0) {
 133                 return;
 134             }
 135             // JTextArea.setText() posts two different events (remove & insert).
 136             // Since we make no differences between text events,
 137             // the document listener has to be disabled while
 138             // JTextArea.setText() is called.
 139             final Document document = getTextComponent().getDocument();
 140             document.removeDocumentListener(this);
 141             getTextComponent().setText(l);
 142             revalidate();
 143             if (firstChangeSkipped) {
 144                 postEvent(new TextEvent(getTarget(),
 145                                         TextEvent.TEXT_VALUE_CHANGED));
 146             }
 147             document.addDocumentListener(this);
 148         }
 149         repaintPeer();
 150     }
 151 
 152     @Override
 153     public final int getSelectionStart() {
 154         synchronized (getDelegateLock()) {
 155             return getTextComponent().getSelectionStart();
 156         }
 157     }
 158 
 159     @Override
 160     public final int getSelectionEnd() {
 161         synchronized (getDelegateLock()) {
 162             return getTextComponent().getSelectionEnd();
 163         }
 164     }
 165 
 166     @Override
 167     public final void select(final int selStart, final int selEnd) {
 168         synchronized (getDelegateLock()) {
 169             getTextComponent().select(selStart, selEnd);
 170         }
 171         repaintPeer();
 172     }
 173 
 174     @Override
 175     public final void setCaretPosition(final int pos) {
 176         synchronized (getDelegateLock()) {
 177             getTextComponent().setCaretPosition(pos);
 178         }
 179         repaintPeer();
 180     }
 181 
 182     @Override
 183     public final int getCaretPosition() {
 184         synchronized (getDelegateLock()) {
 185             return getTextComponent().getCaretPosition();
 186         }
 187     }
 188 
 189     @Override
 190     public final InputMethodRequests getInputMethodRequests() {
 191         synchronized (getDelegateLock()) {
 192             return getTextComponent().getInputMethodRequests();
 193         }
 194     }
 195 
 196     @Override
 197     public final boolean isFocusable() {
 198         return getTarget().isFocusable();
 199     }
 200 
 201     protected final void revalidate() {
 202         synchronized (getDelegateLock()) {
 203             getTextComponent().invalidate();
 204             getDelegate().validate();
 205         }
 206     }
 207 
 208     protected final void postTextEvent() {
 209         postEvent(new TextEvent(getTarget(), TextEvent.TEXT_VALUE_CHANGED));
 210         synchronized (getDelegateLock()) {
 211             revalidate();
 212         }
 213     }
 214 
 215     @Override
 216     public final void changedUpdate(final DocumentEvent e) {
 217         postTextEvent();
 218     }
 219 
 220     @Override
 221     public final void insertUpdate(final DocumentEvent e) {
 222         postTextEvent();
 223     }
 224 
 225     @Override
 226     public final void removeUpdate(final DocumentEvent e) {
 227         postTextEvent();
 228     }
 229 
 230     @Override
 231     public void inputMethodTextChanged(InputMethodEvent event) {
 232         synchronized (getDelegateLock()) {
 233             AWTAccessor.getComponentAccessor().processEvent(getTextComponent(), event);
 234         }
 235     }
 236 
 237     @Override
 238     public void caretPositionChanged(InputMethodEvent event) {
 239         synchronized (getDelegateLock()) {
 240             AWTAccessor.getComponentAccessor().processEvent(getTextComponent(), event);
 241         }
 242     }
 243 }