环境:jdk1.2+
包:

import java.awt.BorderLayout;
import java.awt.Color;

import java.awt.Font;
import java.awt.Point;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.Timer;
import java.util.TimerTask;
import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;

主类:MousePixInfo3(main内实例化)

第一步:设计界面
构造函数内渲染jframe
过程略..

第二步:调用标准库:
利用Robot.getPixelColor(x,y)方法得到Color对象;
利用MouseInfo.getPointerInfo().getLocation()得到Point对象;
利用Integer.toHexString(int i)方法将rgb值转成更易读的十六进制;
利用Timer.schedule(TimerTask timerTask)周期刷新像素信息;

第三步:扩展功能:
1.jframe置顶(Jframe.setAlwaysOnTop(true))(非聚焦)
2.esc键退出(System.exit(0))
3.空格暂停(timer.cancel())
4.L键将坐标值存入系统剪切板
5.C键将颜色值存入系统剪切板

源码:

package test;

import java.awt.BorderLayout;
import java.awt.Color;
import java.awt.Font;
import java.awt.Point;
import java.awt.Robot;
import java.awt.Toolkit;
import java.awt.datatransfer.Clipboard;
import java.awt.datatransfer.StringSelection;
import java.awt.datatransfer.Transferable;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import java.util.Timer;
import java.util.TimerTask;

import javax.swing.JFrame;
import javax.swing.JLabel;
import javax.swing.JPanel;
import javax.swing.border.EmptyBorder;

public class MousePixInfo3 extends JFrame {

    /**
     * 
     */
    private static final long serialVersionUID = 1L;
    private final JPanel contentPanel = new JPanel();
    static JLabel value_x = null;
    static JLabel value_y = null;
    static JLabel myPixColorHex = null;
    static Robot myRobot;
    static Timer timer = new Timer();
    JLabel lblx = new JLabel("X :");
    JLabel lbly = new JLabel("Y :");
    static boolean isRunning = true;
    JLabel note1;
    JLabel note2;

    /**
     * Launch the application.
     */
    public static void main(String[] args) {
        try {
            myRobot = new Robot();
            MousePixInfo3 info_frame = new MousePixInfo3();
            info_frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            info_frame.setVisible(true);
            info_frame.setAlwaysOnTop(true);
            info_frame.addKeyListener(new KeyListener() {

                @Override
                public void keyTyped(KeyEvent e) {
                    // TODO Auto-generated method stub

                }

                @Override
                public void keyReleased(KeyEvent e) {
                    // TODO Auto-generated method stub

                }

                @Override
                public void keyPressed(KeyEvent e) {
                    // TODO Auto-generated method stub
                    if (e.getKeyCode() == KeyEvent.VK_ESCAPE) {
                        System.exit(0);
                    } else if (e.getKeyChar() == ' ') {
                        if (isRunning) {
                            timer.cancel();
                            isRunning = false;
                        } else {
                            run();
                            isRunning = true;
                        }
                    } else if (e.getKeyChar() == 'l') {
                        setSysClipboardText(value_x.getText() + "," + value_y.getText());
                    } else if (e.getKeyChar() == 'c') {
                        setSysClipboardText(myPixColorHex.getText());

                    }
                }
            });
            run();
        } catch (Exception e) {
            e.printStackTrace();
        }
    }

    /**
     * Create the dialog.
     */

    public static void setSysClipboardText(String writeMe) {
        Clipboard clip = Toolkit.getDefaultToolkit().getSystemClipboard();
        Transferable tText = new StringSelection(writeMe);
        clip.setContents(tText, null);
    }

    public static void run() {
        timer = new Timer();
        timer.schedule(new TimerTask() {
            @Override
            public void run() {
                Point point = java.awt.MouseInfo.getPointerInfo().getLocation();
                Color myPixColor = myRobot.getPixelColor(point.x, point.y);
                String r = Integer.toHexString(myPixColor.getRed());
                String g = Integer.toHexString(myPixColor.getGreen());
                String b = Integer.toHexString(myPixColor.getBlue());

                value_x.setText("" + point.x); // 双引号""把int转成string
                value_y.setText("" + point.y);
                myPixColorHex.setText("#" + r + g + b);
            }
        }, 100, 50);// 设置100ms后开始,每50ms检测一次坐标
    }

    public MousePixInfo3() {
        timer = new Timer();
        setTitle("像素采集神器");
        setBounds(100, 100, 317, 192);
        getContentPane().setLayout(new BorderLayout());
        contentPanel.setBorder(new EmptyBorder(5, 5, 5, 5));
        getContentPane().add(contentPanel, BorderLayout.CENTER);
        contentPanel.setLayout(null);

        lblx.setFont(new Font("宋体", Font.PLAIN, 15));
        lblx.setBounds(22, 27, 66, 31);
        contentPanel.add(lblx);

        lbly.setFont(new Font("宋体", Font.PLAIN, 15));
        lbly.setBounds(22, 68, 66, 31);
        contentPanel.add(lbly);

        value_x = new JLabel("0");
        value_x.setForeground(Color.BLUE);
        value_x.setFont(new Font("宋体", Font.PLAIN, 20));
        value_x.setBounds(64, 27, 66, 31);
        contentPanel.add(value_x);

        value_y = new JLabel("0");
        value_y.setForeground(Color.BLUE);
        value_y.setFont(new Font("宋体", Font.PLAIN, 20));
        value_y.setBounds(64, 68, 66, 31);
        contentPanel.add(value_y);

        myPixColorHex = new JLabel("0");
        myPixColorHex.setForeground(Color.RED);
        myPixColorHex.setFont(new Font("宋体", Font.PLAIN, 32));
        myPixColorHex.setBounds(142, 48, 128, 31);
        contentPanel.add(myPixColorHex);

        note1 = new JLabel("esc退出;Space暂停/继续", JLabel.CENTER);
        note1.setFont(new Font("幼圆", Font.PLAIN, 16));
        getContentPane().add(note1, BorderLayout.SOUTH);

        note2 = new JLabel("'l'复制location;'c'复制color", JLabel.CENTER);
        note2.setFont(new Font("幼圆", Font.PLAIN, 16));
        getContentPane().add(note2, BorderLayout.NORTH);

    }
}