graphics 技术.txt

适合初学者练习 包括awt小程序、list和map群体等100多个java程序

Graphics 技术 List.1 GraphicsApp/GraphicsApp.java 
Graphics 技术 List.2 Gradient/Gradient.java 
Graphics 技术 List.3 FontDemo/FontDemo.java 
Graphics 技术 List.4 ShowPic/ShowPic.java 
Graphics 技术 List.5 Offscreen/Offscreen.java 
Graphics 技术 List.6 Filter/Filter.java 
Graphics 技术 List.7 SwingPic/SwingPic.java 
Graphics 技术 List.8 Animation/Animation.java 

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Graphics 技术 List.1 GraphicsApp/GraphicsApp.java 
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001: import javax.swing.*;
002: import java.awt.*;
003: import java.awt.event.*;
004: 
005: public class GraphicsApp extends JFrame {
006: 
007: // Constructor 
008:  public GraphicsApp() {
009:   // Select local system look and feel
010:   try {
011:    UIManager.setLookAndFeel(
012:     UIManager.getCrossPlatformLookAndFeelClassName());
013:   } catch (Exception e) { }
014:   // End program when window closes
015:   addWindowListener(new WindowAdapter() {
016:    public void windowClosing(WindowEvent e) {
017:     System.exit(0);
018:    }
019:   });
020:  }
021: 
022:  public void paint(Graphics g) {
023:   // Get window size
024:   Rectangle r = getBounds(null);
025:   // Paint background yellow
026:   g.setColor(Color.yellow);
027:   g.fillRect(0, 0, r.width, r.height);
028:   // Outline window in black
029:   g.setColor(Color.black);
030:   g.drawRect(0, 0, r.width, r.height);
031:   // Draw grid inside window
032:   for (int h = 0; h < r.height; h += 10)
033:    g.drawLine(0, h, r.width, h);
034:   for (int v = 0; v < r.width; v += 10)
035:    g.drawLine(v, 0, v, r.height);
036:   // Draw overlapping round rectangles
037:   int cx = r.width / 8;
038:   int cy = r.height / 3;
039:   int w = (r.width / 4) * 3;
040:   int h = cy;
041:   g.setColor(Color.gray);
042:   g.fillRoundRect(cx - 4, cy - 4, w, h, 10, 10);
043:   g.setColor(Color.blue);
044:   g.fillRoundRect(cx + 4, cy + 4, w, h, 10, 10);
045:   // Draw text inside outer rectangle
046:   Font f = new Font("TimesRoman", 
047:    Font.BOLD + Font.ITALIC, 24);
048:   g.setFont(f);
049:   g.setColor(Color.orange);
050:   g.drawString("
Java学习源代码检索系统", cx + 25, cy + 36);
051:   g.drawString("Graphics Demonstration", cx + 35, cy + 66);
052:  }
053: 
054:  public static void main(String[] args) {
055:   GraphicsApp app = new GraphicsApp();
056:   app.setTitle("Graphics Demonstration (application)");
057:   app.setSize(450, 280);
058:   app.show();
059:  }
060: }

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Graphics 技术 List.2 Gradient/Gradient.java 
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001: import javax.swing.*;
002: import java.awt.*;
003: import java.awt.event.*;
004: 
005: public class Gradient extends JFrame {
006: 
007: // Constructor 
008:  public Gradient() {
009:   // Select local system look and feel
010:   try {
011:    UIManager.setLookAndFeel(
012:     UIManager.getCrossPlatformLookAndFeelClassName());
013:   } catch (Exception e) { }
014:   // End program when window closes
015:   addWindowListener(new WindowAdapter() {
016:    public void windowClosing(WindowEvent e) {
017:     System.exit(0);
018:    }
019:   });
020:  }
021: 
022:  public void paint(Graphics g) {
023:   int increment = 40;
024:   Rectangle r = getBounds(null);
025:   Color c = new Color(50, 255, 50);
026:   int x = 0;
027:   while (x < r.width) {
028:    g.setColor(c);
029:    g.fillRect(x, 0, x + increment, r.height);
030:    c = c.darker();
031:    x += increment;
032:   }
033:  }
034: 
035:  public static void main(String[] args) {
036:   Gradient app = new Gradient();
037:   app.setTitle("Gradient Color Demonstration");
038:   app.setSize(320, 240);
039:   app.show();
040:  }
041: }

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Graphics 技术 List.3 FontDemo/FontDemo.java 
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001: import javax.swing.*;
002: import javax.swing.event.*;
003: import java.awt.*;
004: import java.awt.event.*;
005: 
006: // Window frame class for showing selected font sample
007: class FontSample extends JFrame {
008:  Font font;    // Currently shown font
009:  String text;  // Sample text to display
010: 
011:  // Constructor
012:  public FontSample() {
013:   super();
014:   font = null;
015:   text = "Abcdefg 1234567890 !@#$%^&*()";
016:   setDefaultCloseOperation(JFrame.HIDE_ON_CLOSE);
017:   setSize(425, 120);
018:  }
019: 
020:  // Called before showing window
021:  public void changeFont(Font f) {
022:   font = f.deriveFont(24.0f);   // Resize to 24 pts
023:   setTitle(font.getFontName()); // Title = font name
024:   if (isShowing()) repaint();   // Repaint if already visible
025:  }
026: 
027:  // Paint sample text using current font in window
028:  public void paint(Graphics g) {
029:   Rectangle r = getBounds(null);
030:   g.setColor(Color.white);  // Erase background to white
031:   g.fillRect(0, 0, r.width, r.height);
032:   if (font != null) {
033:    g.setFont(font);
034:    g.setColor(Color.black);
035:    g.drawString(text, 10, r.height / 2);
036:   }
037:  }
038: }
039: 
040: // Main program class
041: public class FontDemo extends JFrame {
042:  final protected Font[] fonts;           // Array of fonts
043:  final protected FontSample fontSample;  // Sample window
044: 
045: // Constructor 
046:  public FontDemo() {
047:   super();
048:   // Select local system look and feel
049:   try {
050:    UIManager.setLookAndFeel(
051:     UIManager.getSystemLookAndFeelClassName());
052:   } catch (Exception e) { }
053:   // End program when window closes
054:   addWindowListener(new WindowAdapter() {
055:    public void windowClosing(WindowEvent e) {
056:     System.exit(0);
057:    }
058:   });
059: 
060:   // Create child sample font window
061:   fontSample = new FontSample();
062: 
063:   // Loading fonts may take a while; tell user
064:   System.out.print("Loading font names...");
065: 
066:   // Get available fonts in 1pt sizes
067:   GraphicsEnvironment ge = 
068:    GraphicsEnvironment.getLocalGraphicsEnvironment();
069:   fonts = ge.getAllFonts();
070: 
071:   // Create a JComboBox object for listing font names
072:   JComboBox fontBox = new JComboBox();
073:   for (int i = 0; i < fonts.length; i++)
074:    fontBox.addItem(fonts[i].getFontName());
075:   fontBox.setEditable(false);
076: 
077:   // Respond to item selection
078:   fontBox.addActionListener(
079:    new ActionListener() {
080:     public void actionPerformed(ActionEvent e) {
081:      JComboBox box = (JComboBox)e.getSource();
082:      int fontIndex = box.getSelectedIndex();
083:      fontSample.changeFont(fonts[fontIndex]);
084:      fontSample.show();
085:     }
086:    }
087:   );
088:   
089:   System.out.println("/nSelect font for a sample"); 
090:   Container content = getContentPane();
091:   content.setLayout(new FlowLayout());
092:   content.add(new JLabel("Available fonts"));
093:   content.add(fontBox);
094:  }
095: 
096:  public static void main(String[] args) {
097:   FontDemo app = new FontDemo();
098:   app.setTitle("Font Demonstration");
099:   app.setSize(320, 240);
100:   app.show();
101:  }
102: }

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Graphics 技术 List.4 ShowPic/ShowPic.java 
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001: import java.applet.*;
002: import java.awt.*;
003: 
004: public class ShowPic extends Applet
005:  implements Runnable {
006: 
007:  // Instance variables
008:  Image pic;             // GIF image producer
009:  int picID;             // Arbitrary image ID
010:  MediaTracker tracker;  // Tracks loading of image
011:  Thread loadingThread;  // Thread for loading image
012:  String filename = "ksc-01pp-0287.jpg";  // File name
013: 
014:  // Initialize applet
015:  public void init() {
016:   // Create MediaTracker object
017:   tracker = new MediaTracker(this);
018:   // Start image loading
019:   pic = getImage(getDocumentBase(), filename);
020:   picID = 0;
021:   tracker.addImage(pic, picID);
022:   // Create thread to monitor image loading
023:   loadingThread = new Thread(this);
024:   loadingThread.start();
025:  }
026: 
027:  // Run loading thread
028:  // Allows other processes to run while loading
029:  // the image data
030:  public void run() {
031:   try {
032:    tracker.waitForID(picID);
033:   } catch (InterruptedException ie) {
034:    return;
035:   }
036:   repaint();  // Cause paint() to draw loaded image
037:  }
038: 
039:  // Paint window contents
040:  // Displays loading or error message until
041:  // image is ready, then shows image
042:  public void paint(Graphics g) {
043:   if (tracker.isErrorID(picID))
044:    g.drawString("Error loading " + filename, 10, 20);
045:   else if (tracker.checkID(picID))
046:    g.drawImage(pic, 0, 0, this);
047:   else
048:    g.drawString("Loading " + filename, 10, 20);
049:  }
050: }

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Graphics 技术 List.5 Offscreen/Offscreen.java 
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001: import java.applet.*;
002: import java.awt.*;
003: import java.util.Random;
004: 
005: public class Offscreen extends Applet
006:  implements Runnable {
007: 
008:  // Instance variables
009:  Thread drawingThread;
010:  Image offscreenImage;
011:  Graphics offscreenContext;
012:  Random gen;
013:  boolean imageReady = false;
014:  int imageW, imageH;
015:  int numOvals = 100;
016: 
017:  // Initialize applet
018:  public void init() {
019:   // Size applet window
020:   imageW = 320;
021:   imageH = 240;
022:   resize(imageW, imageH);
023:   // Construct random number generator
024:   gen = new Random();
025:   // Create offscreen image and Graphics context
026:   offscreenImage = createImage(imageW, imageH);
027:   offscreenContext = offscreenImage.getGraphics();
028:  }
029: 
030:  // Create and start drawing thread
031:  public void start() {