Blog

AWT Image Class

  • Post author:
  • Post category:AWT
  • Post comments:1 Comment
Image class

Introduction

Image class control is the superclass for all image classes representing graphical images.

Class declaration

The Following is the declaration for java.awt.Image class:

public abstract class Image
   extends Object

Field

Following are the fields for java.awt.Image class:

  • protected float accelerationPriority — Priority for accelerating this image.
  • static int SCALE_AREA_AVERAGING — Use the Area Averaging image scaling algorithm.
  • static int SCALE_DEFAULT — Use the default image-scaling algorithm.
  • static int SCALE_FAST — Choose an image-scaling algorithm that gives higher priority to scaling speed than smoothness of the scaled image.
  • static int SCALE_REPLICATE — Use the image scaling algorithm embodied in the ReplicateScaleFilter class.
  • static int SCALE_SMOOTH — Choose an image-scaling algorithm that gives higher priority to image smoothness than scaling speed.
  • static Object UndefinedProperty — The UndefinedProperty object should be returned whenever a property which was not defined for a particular image is fetched.

Class constructors

S.N.Constructor & Description
1Image()

Class methods

S.N.Method & Description
1void flush()Flushes all reconstructable resources being used by this Image object.
2float getAccelerationPriority()Returns the current value of the acceleration priority hint.
3ImageCapabilities getCapabilities(GraphicsConfiguration gc)Returns an ImageCapabilities object which can be inquired as to the capabilities of this Image on the specified GraphicsConfiguration.
4abstract Graphics getGraphics()Creates a graphics context for drawing to an off-screen image.
5abstract int getHeight(ImageObserver observer)Determines the height of the image.
6abstract Object getProperty(String name, ImageObserver observer)Gets a property of this image by name.
7Image getScaledInstance(int width, int height, int hints)Creates a scaled version of this image.
8abstract ImageProducer getSource()Gets the object that produces the pixels for the image.
9abstract int getWidth(ImageObserver observer)Determines the width of the image.
10void setAccelerationPriority(float priority)Sets a hint for this image about how important acceleration is.

Methods inherited

This class inherits methods from the following classes:

  • java.lang.Object

Image Example

Create the following java program using any editor of your choice in say D:/ > AWT > com > adglob > gui >AwtControlDemo.java

package com.adglob.gui;

import java.awt.*;
import java.awt.event.*;

public class AwtControlDemo {

   private Frame mainFrame;
   private Label headerLabel;
   private Label statusLabel;
   private Panel controlPanel;

   public AwtControlDemo(){
      prepareGUI();
   }

   public static void main(String[] args){
      AwtControlDemo  awtControlDemo = new AwtControlDemo();
      awtControlDemo.showImageDemo();
   }

   private void prepareGUI(){
      mainFrame = new Frame("Java AWT Examples");
      mainFrame.setSize(400,400);
      mainFrame.setLayout(new GridLayout(3, 1));
      mainFrame.addWindowListener(new WindowAdapter() {
         public void windowClosing(WindowEvent windowEvent){
            System.exit(0);
         }        
      });    
      headerLabel = new Label();
      headerLabel.setAlignment(Label.CENTER);
      statusLabel = new Label();        
      statusLabel.setAlignment(Label.CENTER);
      statusLabel.setSize(350,100);

      controlPanel = new Panel();
      controlPanel.setLayout(new FlowLayout());

      mainFrame.add(headerLabel);
      mainFrame.add(controlPanel);
      mainFrame.add(statusLabel);
      mainFrame.setVisible(true);  
   }

   private void showImageDemo(){
      headerLabel.setText("Control in action: Image"); 

      controlPanel.add(new ImageComponent("resources/java.jpg"));
      mainFrame.setVisible(true);  
   }
	
   class ImageComponent extends Component {

      BufferedImage img;

      public void paint(Graphics g) {
         g.drawImage(img, 0, 0, null);
      }

      public ImageComponent(String path) {
         try {
            img = ImageIO.read(new File(path));
         } catch (IOException e) {
            e.printStackTrace();
         }
      }

      public Dimension getPreferredSize() {
         if (img == null) {
            return new Dimension(100,100);
         } else {
            return new Dimension(img.getWidth(), img.getHeight());
         }
      }
   }
}

Compile the program using the command prompt. Go to D:/ > AWT and type the following command.

D:\AWT>javac com\adglob\gui\AwtControlDemo.java

If no error comes that means compilation is successful. Run the program using the following command.

D:\AWT>java com.adglob.gui.AwtControlDemo

Verify the following output

Image class

Previous Page:-Click Here

This Post Has One Comment

Leave a Reply