import java.io.*;
import java.net.*;
import java.awt.*;
import java.awt.event.*;
import java.awt.geom.AffineTransform;
import java.awt.image.*;
import javax.imageio.*;
import javax.swing.*;
class ImageDrawingComponent extends Component {
static String descs[] = {
"Simple Copy",
"Scale Up",
"Scale Down",
"Scale Up : Bicubic",
"Convolve : LowPass",
"Convolve : Sharpen",
"RescaleOp",
"LookupOp",
};
int opIndex;
private BufferedImage bi;
int w, h;
public static final float[] SHARPEN3x3 = { // sharpening filter kernel
0.f, -1.f, 0.f,
-1.f, 5.f, -1.f,
0.f, -1.f, 0.f
};
public static final float[] BLUR3x3 = {
0.1f, 0.1f, 0.1f, // low-pass filter kernel
0.1f, 0.2f, 0.1f,
0.1f, 0.1f, 0.1f
};
public ImageDrawingComponent(URL imageSrc) {
try {
bi = ImageIO.read(imageSrc);
w = bi.getWidth(null);
h = bi.getHeight(null);
if (bi.getType() != BufferedImage.TYPE_INT_RGB) {
BufferedImage bi2 =
new BufferedImage(w, h, BufferedImage.TYPE_INT_RGB);
Graphics big = bi2.getGraphics();
big.drawImage(bi, 0, 0, null);
bi = bi2;
}
} catch (IOException e) {
System.out.println("Image could not be read");
System.exit(1);
}
}
public Dimension getPreferredSize() {
return new Dimension(w, h);
}
static String[] getDescriptions() {
return descs;
}
void setOpIndex(int i) {
opIndex = i;
}
/* In this example the image is recalculated on the fly every time
* This makes sense where repaints are infrequent or will use a
* different filter/op from the last.
* In other cases it may make sense to "cache" the results of the
* operation so that unless 'opIndex' changes, drawing is always a
* simple copy.
* In such a case create the cached image and directly apply the filter
* to it and retain the resulting image to be repainted.
* The resulting image if untouched and unchanged Java 2D may potentially
* use hardware features to accelerate the blit.
*/
public void paint(Graphics g) {
Graphics2D g2 = (Graphics2D) g;
switch (opIndex) {
case 0 : /* copy */
g.drawImage(bi, 0, 0, null);
break;
case 1 : /* scale up using coordinates */
g.drawImage(bi,
0, 0, w, h, /* dst rectangle */
0, 0, w/2, h/2, /* src area of image */
null);
break;
case 2 : /* scale down using transform */
g2.drawImage(bi, AffineTransform.getScaleInstance(0.7, 0.7), null);
break;
case 3: /* scale up using transform Op and BICUBIC interpolation */
AffineTransform at = AffineTransform.getScaleInstance(1.5, 1.5);
AffineTransformOp aop =
new AffineTransformOp(at, AffineTransformOp.TYPE_BICUBIC);
g2.drawImage(bi, aop, 0, 0);
break;
case 4: /* low pass filter */
case 5: /* sharpen */
float[] data = (opIndex == 4) ? BLUR3x3 : SHARPEN3x3;
ConvolveOp cop = new ConvolveOp(new Kernel(3, 3, data),
ConvolveOp.EDGE_NO_OP,
null);
g2.drawImage(bi, cop, 0, 0);
break;
case 6 : /* rescale */
RescaleOp rop = new RescaleOp(1.1f, 20.0f, null);
g2.drawImage(bi, rop, 0, 0);
break;
case 7 : /* lookup */
byte lut[] = new byte[256];
for (int j=0; j<256; j++) {
lut[j] = (byte)(256-j);
}
ByteLookupTable blut = new ByteLookupTable(0, lut);
LookupOp lop = new LookupOp(blut, null);
g2.drawImage(bi, lop, 0, 0);
break;
default :
}
}
}
public class ImageDrawingApplet extends JApplet {
static String imageFileName = "bld.jpg";
private URL imageSrc;
public ImageDrawingApplet () {
}
public ImageDrawingApplet (URL imageSrc) {
this.imageSrc = imageSrc;
}
public void init() {
try {
imageSrc = new URL(getCodeBase(), imageFileName);
} catch (MalformedURLException e) {
}
buildUI();
}
public void buildUI() {
final ImageDrawingComponent id = new ImageDrawingComponent(imageSrc);
add("Center", id);
JComboBox choices = new JComboBox(id.getDescriptions());
choices.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
JComboBox cb = (JComboBox)e.getSource();
id.setOpIndex(cb.getSelectedIndex());
id.repaint();
};
});
add("South", choices);
}
public static void main(String s[]) {
JFrame f = new JFrame("ImageDrawing");
f.addWindowListener(new WindowAdapter() {
public void windowClosing(WindowEvent e) {System.exit(0);}
});
URL imageSrc = null;
try {
imageSrc = ((new File(imageFileName)).toURI()).toURL();
} catch (MalformedURLException e) {
}
ImageDrawingApplet id = new ImageDrawingApplet(imageSrc);
id.buildUI();
f.add("Center", id);
f.pack();
f.setVisible(true);
}
}What's wrong with this code.
It shows these error message.
init:
deps-jar:
Created dir: C:\Documents and Settings\Administrator\My Documents\NetBeansProjects\JavaApplication19\build\classes
Compiling 1 source file to C:\Documents and Settings\Administrator\My Documents\NetBeansProjects\JavaApplication19\build\classes
C:\Documents and Settings\Administrator\My Documents\NetBeansProjects\JavaApplication19\src\javaapplication19\Main.java:168: class ImageDrawingApplet is public, should be declared in a file named ImageDrawingApplet.java
public class ImageDrawingApplet extends JApplet {
1 error
BUILD FAILED (total time: 0 seconds)