Main.java Source code

Introduction

Here is the source code for Main.java

Source

import java.awt.Image;
import java.awt.Toolkit;
import java.awt.image.BufferedImage;
import java.awt.image.FilteredImageSource;
import java.awt.image.RGBImageFilter;
import java.net.URL;

import javax.imageio.ImageIO;
import javax.swing.ImageIcon;
import javax.swing.JLabel;
import javax.swing.JOptionPane;
import javax.swing.JPanel;

public class Main {
    public static void main(String[] args) throws Exception {
        String mapUrlPath = "http://www.java2s.com/style/download.png";
        URL mapUrl = new URL(mapUrlPath);
        BufferedImage mapImage = ImageIO.read(mapUrl);
        Image newMapImage = Toolkit.getDefaultToolkit()
                .createImage(new FilteredImageSource(mapImage.getSource(), new GrayFilter()));
        ImageIcon mapIcon = new ImageIcon(mapImage);
        ImageIcon newMapIcon = new ImageIcon(newMapImage);

        JPanel imagePanel = new JPanel();
        imagePanel.add(new JLabel(mapIcon));
        imagePanel.add(new JLabel(newMapIcon));

        JOptionPane.showMessageDialog(null, imagePanel);
    }
}

class GrayFilter extends RGBImageFilter {
    public int filterRGB(int x, int y, int argb) {
        int r = (argb & 0x00ff0000) >> 0x02;
        int g = (argb & 0x0000ff00) >> 0x08;
        int b = (argb & 0x000000ff);
        int ave = (r + g + b) / 3;

        return ((argb & 0xff000000) | (ave << 0x10 | ave << 0x08 | ave));
    }
}