/* * Copyright (c) 1995, 2008, Oracle and/or its affiliates. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * * - Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * * - Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * * - Neither the name of Oracle or the names of its * contributors may be used to endorse or promote products derived * from this software without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "AS * IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, * THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT OWNER OR * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR * PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF * LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING * NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS * SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. */ import javax.swing.*; import java.awt.*; import java.awt.event.*; import java.util.Hashtable; import java.awt.font.FontRenderContext; import java.awt.font.LineBreakMeasurer; import java.awt.font.TextAttribute; import java.awt.font.TextLayout; import java.text.AttributedCharacterIterator; import java.text.AttributedString; /** * This class demonstrates how to line-break and draw a paragraph * of text using LineBreakMeasurer and TextLayout. * * This class constructs a LineBreakMeasurer from an * AttributedCharacterIterator. It uses the LineBreakMeasurer * to create and draw TextLayouts (lines of text) which fit within * the Component's width. */ class LineBreakPanel extends JPanel { // The LineBreakMeasurer used to line-break the paragraph. private LineBreakMeasurer lineMeasurer; // index of the first character in the paragraph. private int paragraphStart; // index of the first character after the end of the paragraph. private int paragraphEnd; private static final Hashtable map = new Hashtable(); static { map.put(TextAttribute.FAMILY, "Serif"); map.put(TextAttribute.SIZE, new Float(18.0)); } private static AttributedString vanGogh = new AttributedString( "Many people believe that Vincent van Gogh painted his best works " + "during the two-year period he spent in Provence. Here is where he " + "painted The Starry Night--which some consider to be his greatest " + "work of all. However, as his artistic brilliance reached new " + "heights in Provence, his physical and mental health plummeted. ", map); public void paintComponent(Graphics g) { super.paintComponent(g); setBackground(Color.white); Graphics2D g2d = (Graphics2D)g; // Create a new LineBreakMeasurer from the paragraph. // It will be cached and re-used. if (lineMeasurer == null) { AttributedCharacterIterator paragraph = vanGogh.getIterator(); paragraphStart = paragraph.getBeginIndex(); paragraphEnd = paragraph.getEndIndex(); FontRenderContext frc = g2d.getFontRenderContext(); lineMeasurer = new LineBreakMeasurer(paragraph, frc); } // Set break width to width of Component. float breakWidth = (float)getSize().width; float drawPosY = 0; // Set position to the index of the first character in the paragraph. lineMeasurer.setPosition(paragraphStart); // Get lines until the entire paragraph has been displayed. while (lineMeasurer.getPosition() < paragraphEnd) { // Retrieve next layout. A cleverer program would also cache // these layouts until the component is re-sized. TextLayout layout = lineMeasurer.nextLayout(breakWidth); // Compute pen x position. If the paragraph is right-to-left we // will align the TextLayouts to the right edge of the panel. // Note: this won't occur for the English text in this sample. // Note: drawPosX is always where the LEFT of the text is placed. float drawPosX = layout.isLeftToRight() ? 0 : breakWidth - layout.getAdvance(); // Move y-coordinate by the ascent of the layout. drawPosY += layout.getAscent(); // Draw the TextLayout at (drawPosX, drawPosY). layout.draw(g2d, drawPosX, drawPosY); // Move y-coordinate in preparation for next layout. drawPosY += layout.getDescent() + layout.getLeading(); } } } public class LineBreakSample extends JApplet { public void init() { buildUI(getContentPane()); } public void buildUI(Container container) { try { String cn = UIManager.getSystemLookAndFeelClassName(); UIManager.setLookAndFeel(cn); } catch (Exception cnf) { } LineBreakPanel lineBreakPanel = new LineBreakPanel(); container.add(lineBreakPanel, BorderLayout.CENTER); } public static void main(String[] args) { JFrame f = new JFrame("Line Break Sample"); f.addWindowListener(new WindowAdapter(){ public void windowClosing(WindowEvent e) { System.exit(0); } }); LineBreakSample lineBreakSample = new LineBreakSample(); lineBreakSample.buildUI(f.getContentPane()); f.setSize(new Dimension(400, 250)); f.setVisible(true); } }