/* * Copyright (c) 1997, 2011, 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 nor 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. */ /* * This source code is provided to illustrate the usage of a given feature * or technique and has been deliberately simplified. Additional steps * required for a production-quality application, such as security checks, * input validation and proper error handling, might not be present in * this sample code. */ import java.awt.*; import java.awt.event.*; import java.applet.*; /** * An interactive test of the Graphics.drawArc and Graphics.fillArc * routines. Can be run either as a standalone application by * typing "java ArcTest" or as an applet in the AppletViewer. */ @SuppressWarnings("serial") public class ArcTest extends Applet { ArcControls controls; // The controls for marking and filling arcs ArcCanvas canvas; // The drawing area to display arcs @Override public void init() { setLayout(new BorderLayout()); canvas = new ArcCanvas(); add("Center", canvas); add("South", controls = new ArcControls(canvas)); } @Override public void destroy() { remove(controls); remove(canvas); } @Override public void start() { controls.setEnabled(true); } @Override public void stop() { controls.setEnabled(false); } @Override public void processEvent(AWTEvent e) { if (e.getID() == Event.WINDOW_DESTROY) { System.exit(0); } } public static void main(String args[]) { Frame f = new Frame("ArcTest"); ArcTest arcTest = new ArcTest(); arcTest.init(); arcTest.start(); f.add("Center", arcTest); f.setSize(300, 300); f.setVisible(true); } @Override public String getAppletInfo() { return "An interactive test of the Graphics.drawArc and \nGraphics." + "fillArc routines. Can be run \neither as a standalone " + "application by typing 'java ArcTest' \nor as an applet in " + "the AppletViewer."; } } @SuppressWarnings("serial") class ArcCanvas extends Canvas { int startAngle = 0; int extent = 45; boolean filled = false; Font font = new java.awt.Font("SansSerif", Font.PLAIN, 12); @Override public void paint(Graphics g) { Rectangle r = getBounds(); int hlines = r.height / 10; int vlines = r.width / 10; g.setColor(Color.pink); for (int i = 1; i <= hlines; i++) { g.drawLine(0, i * 10, r.width, i * 10); } for (int i = 1; i <= vlines; i++) { g.drawLine(i * 10, 0, i * 10, r.height); } g.setColor(Color.red); if (filled) { g.fillArc(0, 0, r.width - 1, r.height - 1, startAngle, extent); } else { g.drawArc(0, 0, r.width - 1, r.height - 1, startAngle, extent); } g.setColor(Color.black); g.setFont(font); g.drawLine(0, r.height / 2, r.width, r.height / 2); g.drawLine(r.width / 2, 0, r.width / 2, r.height); g.drawLine(0, 0, r.width, r.height); g.drawLine(r.width, 0, 0, r.height); int sx = 10; int sy = r.height - 28; g.drawString("Start = " + startAngle, sx, sy); g.drawString("Extent = " + extent, sx, sy + 14); } public void redraw(boolean filled, int start, int extent) { this.filled = filled; this.startAngle = start; this.extent = extent; repaint(); } } @SuppressWarnings("serial") class ArcControls extends Panel implements ActionListener { TextField startTF; TextField extentTF; ArcCanvas canvas; @SuppressWarnings("LeakingThisInConstructor") public ArcControls(ArcCanvas canvas) { Button b = null; this.canvas = canvas; add(startTF = new IntegerTextField("0", 4)); add(extentTF = new IntegerTextField("45", 4)); b = new Button("Fill"); b.addActionListener(this); add(b); b = new Button("Draw"); b.addActionListener(this); add(b); } @Override public void actionPerformed(ActionEvent ev) { String label = ev.getActionCommand(); int start, extent; try { start = Integer.parseInt(startTF.getText().trim()); } catch (NumberFormatException ignored) { start = 0; } try { extent = Integer.parseInt(extentTF.getText().trim()); } catch (NumberFormatException ignored) { extent = 0; } canvas.redraw(label.equals("Fill"), start, extent); } } @SuppressWarnings("serial") class IntegerTextField extends TextField { String oldText = null; public IntegerTextField(String text, int columns) { super(text, columns); enableEvents(AWTEvent.KEY_EVENT_MASK | AWTEvent.TEXT_EVENT_MASK); oldText = getText(); } // Consume non-digit KeyTyped events // Note that processTextEvent kind of eliminates the need for this // function, but this is neater, since ideally, it would prevent // the text from appearing at all. Sigh. See bugid 4100317/4114565. // @Override protected void processEvent(AWTEvent evt) { int id = evt.getID(); if (id != KeyEvent.KEY_TYPED) { super.processEvent(evt); return; } KeyEvent kevt = (KeyEvent) evt; char c = kevt.getKeyChar(); // Digits, backspace, and delete are okay // Note that the minus sign is allowed, but not the decimal if (Character.isDigit(c) || (c == '\b') || (c == '\u007f') || (c == '\u002d')) { super.processEvent(evt); return; } Toolkit.getDefaultToolkit().beep(); kevt.consume(); } // Should consume TextEvents for non-integer Strings // Store away the text in the tf for every TextEvent // so we can revert to it on a TextEvent (paste, or // legal key in the wrong location) with bad text // @Override protected void processTextEvent(TextEvent te) { // The empty string is okay, too String newText = getText(); if (newText.equals("") || textIsInteger(newText)) { oldText = newText; super.processTextEvent(te); return; } Toolkit.getDefaultToolkit().beep(); setText(oldText); } // Returns true for Integers (zero and negative // values are allowed). // Note that the empty string is not allowed. // private boolean textIsInteger(String textToCheck) { try { Integer.parseInt(textToCheck, 10); return true; } catch (NumberFormatException ignored) { return false; } } }