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* DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER.
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* particular file as subject to the "Classpath" exception as provided
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*
* 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).
*
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*
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package sun.awt.im;
import java.awt.AWTEvent;
import java.awt.Color;
import java.awt.Dimension;
import java.awt.FontMetrics;
import java.awt.Graphics;
import java.awt.Graphics2D;
import java.awt.Point;
import java.awt.Rectangle;
import java.awt.Toolkit;
import java.awt.event.InputMethodEvent;
import java.awt.event.InputMethodListener;
import java.awt.event.WindowEvent;
import java.awt.event.WindowAdapter;
import java.awt.font.FontRenderContext;
import java.awt.font.TextHitInfo;
import java.awt.font.TextLayout;
import java.awt.geom.Rectangle2D;
import java.awt.im.InputMethodRequests;
import java.text.AttributedCharacterIterator;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.border.LineBorder;
/**
* A composition area is used to display text that's being composed
* using an input method in its own user interface environment,
* typically in a root window.
*
* @author JavaSoft International
*/
// This class is final due to the 6607310 fix. Refer to the CR for details.
public final class CompositionArea extends JPanel implements InputMethodListener {
private CompositionAreaHandler handler;
private TextLayout composedTextLayout;
private TextHitInfo caret = null;
private JFrame compositionWindow;
private static final int TEXT_ORIGIN_X = 5;
private static final int TEXT_ORIGIN_Y = 15;
private static final int PASSIVE_WIDTH = 480;
private static final int WIDTH_MARGIN=10;
private static final int HEIGHT_MARGIN=3;
CompositionArea() {
// create composition window with localized title
String windowTitle = Toolkit.getProperty("AWT.CompositionWindowTitle", "Input Window");
compositionWindow =
(JFrame)InputMethodContext.createInputMethodWindow(windowTitle, null, true);
setOpaque(true);
setBorder(LineBorder.createGrayLineBorder());
setForeground(Color.black);
setBackground(Color.white);
// if we get the focus, we still want to let the client's
// input context handle the event
enableInputMethods(true);
enableEvents(AWTEvent.KEY_EVENT_MASK);
compositionWindow.getContentPane().add(this);
compositionWindow.addWindowListener(new FrameWindowAdapter());
addInputMethodListener(this);
compositionWindow.enableInputMethods(false);
compositionWindow.pack();
Dimension windowSize = compositionWindow.getSize();
Dimension screenSize = (getToolkit()).getScreenSize();
compositionWindow.setLocation(screenSize.width - windowSize.width-20,
screenSize.height - windowSize.height-100);
compositionWindow.setVisible(false);
}
/**
* Sets the composition area handler that currently owns this
* composition area, and its input context.
*/
synchronized void setHandlerInfo(CompositionAreaHandler handler, InputContext inputContext) {
this.handler = handler;
((InputMethodWindow) compositionWindow).setInputContext(inputContext);
}
/**
* @see java.awt.Component#getInputMethodRequests
*/
public InputMethodRequests getInputMethodRequests() {
return handler;
}
// returns a 0-width rectangle
private Rectangle getCaretRectangle(TextHitInfo caret) {
int caretLocation = 0;
TextLayout layout = composedTextLayout;
if (layout != null) {
caretLocation = Math.round(layout.getCaretInfo(caret)[0]);
}
Graphics g = getGraphics();
FontMetrics metrics = null;
try {
metrics = g.getFontMetrics();
} finally {
g.dispose();
}
return new Rectangle(TEXT_ORIGIN_X + caretLocation,
TEXT_ORIGIN_Y - metrics.getAscent(),
0, metrics.getAscent() + metrics.getDescent());
}
public void paint(Graphics g) {
super.paint(g);
g.setColor(getForeground());
TextLayout layout = composedTextLayout;
if (layout != null) {
layout.draw((Graphics2D) g, TEXT_ORIGIN_X, TEXT_ORIGIN_Y);
}
if (caret != null) {
Rectangle rectangle = getCaretRectangle(caret);
g.setXORMode(getBackground());
g.fillRect(rectangle.x, rectangle.y, 1, rectangle.height);
g.setPaintMode();
}
}
// shows/hides the composition window
void setCompositionAreaVisible(boolean visible) {
compositionWindow.setVisible(visible);
}
// returns true if composition area is visible
boolean isCompositionAreaVisible() {
return compositionWindow.isVisible();
}
// workaround for the Solaris focus lost problem
class FrameWindowAdapter extends WindowAdapter {
public void windowActivated(WindowEvent e) {
requestFocus();
}
}
// InputMethodListener methods - just forward to the current handler
public void inputMethodTextChanged(InputMethodEvent event) {
handler.inputMethodTextChanged(event);
}
public void caretPositionChanged(InputMethodEvent event) {
handler.caretPositionChanged(event);
}
/**
* Sets the text and caret to be displayed in this composition area.
* Shows the window if it contains text, hides it if not.
*/
void setText(AttributedCharacterIterator composedText, TextHitInfo caret) {
composedTextLayout = null;
if (composedText == null) {
// there's no composed text to display, so hide the window
compositionWindow.setVisible(false);
this.caret = null;
} else {
/* since we have composed text, make sure the window is shown.
This is necessary to get a valid graphics object. See 6181385.
*/
if (!compositionWindow.isVisible()) {
compositionWindow.setVisible(true);
}
Graphics g = getGraphics();
if (g == null) {
return;
}
try {
updateWindowLocation();
FontRenderContext context = ((Graphics2D)g).getFontRenderContext();
composedTextLayout = new TextLayout(composedText, context);
Rectangle2D bounds = composedTextLayout.getBounds();
this.caret = caret;
// Resize the composition area to just fit the text.
FontMetrics metrics = g.getFontMetrics();
Rectangle2D maxCharBoundsRec = metrics.getMaxCharBounds(g);
int newHeight = (int)maxCharBoundsRec.getHeight() + HEIGHT_MARGIN;
int newFrameHeight = newHeight +compositionWindow.getInsets().top
+compositionWindow.getInsets().bottom;
// If it's a passive client, set the width always to PASSIVE_WIDTH (480px)
InputMethodRequests req = handler.getClientInputMethodRequests();
int newWidth = (req==null) ? PASSIVE_WIDTH : (int)bounds.getWidth() + WIDTH_MARGIN;
int newFrameWidth = newWidth + compositionWindow.getInsets().left
+ compositionWindow.getInsets().right;
setPreferredSize(new Dimension(newWidth, newHeight));
compositionWindow.setSize(new Dimension(newFrameWidth, newFrameHeight));
// show the composed text
paint(g);
}
finally {
g.dispose();
}
}
}
/**
* Sets the caret to be displayed in this composition area.
* The text is not changed.
*/
void setCaret(TextHitInfo caret) {
this.caret = caret;
if (compositionWindow.isVisible()) {
Graphics g = getGraphics();
try {
paint(g);
} finally {
g.dispose();
}
}
}
/**
* Positions the composition window near (usually below) the
* insertion point in the client component if the client
* component is an active client (below-the-spot input).
*/
void updateWindowLocation() {
InputMethodRequests req = handler.getClientInputMethodRequests();
if (req == null) {
// not an active client
return;
}
Point windowLocation = new Point();
Rectangle caretRect = req.getTextLocation(null);
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
Dimension windowSize = compositionWindow.getSize();
final int SPACING = 2;
if (caretRect.x + windowSize.width > screenSize.width) {
windowLocation.x = screenSize.width - windowSize.width;
} else {
windowLocation.x = caretRect.x;
}
if (caretRect.y + caretRect.height + SPACING + windowSize.height > screenSize.height) {
windowLocation.y = caretRect.y - SPACING - windowSize.height;
} else {
windowLocation.y = caretRect.y + caretRect.height + SPACING;
}
compositionWindow.setLocation(windowLocation);
}
// support for InputMethodRequests methods
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