KeyListener的AWT-EventQueue-0错误

Question

I made 2 objects that moves with keylisteners. They move correctly, but in the console I receive this error every time I press a button:

Exception in thread "AWT-EventQueue-0" java.lang.UnsupportedOperationException: Not supported yet. at CatchMe.CatchMe.keyTyped(CatchMe.java:197)

My code is as follows:

package CatchMe;

import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
import javax.swing.JFrame;
import javax.swing.Timer;

public class CatchMe extends JFrame implements ActionListener, KeyListener {

private Image dbImage;
private Graphics dbg;
int x = 200, y = 300;
int velX, velY;
int velX1, velY1;
int ScoreB1 = 0;
int ScoreR1 = 0;
Timer tm = new Timer(5, this);
long startTime = System.currentTimeMillis();
long onGoing;
String onG;
Dimension screenSize = Toolkit.getDefaultToolkit().getScreenSize();
int width = (int) screenSize.getWidth();
int height = (int) screenSize.getHeight();
int recX = (width + 100) / 2, recY = (height + 100) / 2;

public CatchMe() {
    setSize(width, height);
    setDefaultCloseOperation(EXIT_ON_CLOSE);
    setResizable(false);
    setVisible(true);
    tm.start();
    addKeyListener(this);
    setFocusable(true);
    setFocusTraversalKeysEnabled(false);
}

@Override
public void paint(Graphics g) {
    dbImage = createImage(getWidth(), getHeight());
    dbg = dbImage.getGraphics();
    paintComponent(dbg);
    g.drawImage(dbImage, 0, 0, this);
}

public void paintComponent(Graphics g) {
    Rectangle r1 = new Rectangle(recX, recY, 25, 25);
    Rectangle r2 = new Rectangle(x, y, 25, 25);
    g.setColor(Color.BLUE);
    g.fillRect(r1.x, r1.y, r1.width, r1.height);
    g.setColor(Color.RED);
    g.fillRect(r2.x, r2.y, r2.width, r2.height);
    g.setColor(Color.BLACK);
    g.fillRect(0, 20, 100, 50);
    g.fillRect(100, 20, 100, 50);
    g.fillRect(200, 20, 50, 50);
    g.setColor(Color.YELLOW);
    g.drawString("Score of Blue", 5, 40);
    String ScoreB = ScoreB1 + "";
    g.drawString(ScoreB, 5, 55);
    g.drawString("Score of Red", 110, 40);
    String ScoreR = ScoreR1 + "";
    g.drawString(ScoreR, 110, 55);
    g.drawLine(95, 20, 95, 69);
    g.drawLine(200, 20, 200, 69);
    g.setColor(Color.RED);
    onGoing = (System.currentTimeMillis() - startTime) / 1000;
    onG = onGoing + "";
    g.setColor(Color.YELLOW);
    g.drawString(onG, 220, 50);
    System.out.println(onGoing);
    if (r1.intersects(r2)) {
        if (onGoing <= 60 || (onGoing >= 120 && onGoing < 180)) {
            g.setColor(Color.BLUE);
            g.drawString("Blue Caught You!", 175, 90);
            ScoreB1++;

        } else if (onGoing >= 240) {
            if (ScoreB1 > ScoreR1) {
                Font font = new Font("Jokerman", Font.PLAIN, 50);
                g.setColor(Color.BLUE);
                g.drawString("BLUE WINS", 600, 400);
            } else if (ScoreB1 < ScoreR1) {
                Font font = new Font("Jokerman", Font.PLAIN, 50);
                g.setColor(Color.RED);
                g.drawString("RED WINS", 600, 400);
            }
        } else {
            g.setColor(Color.RED);
            g.drawString("Red Caught You!", 175, 90);
            ScoreR1++;
        }
        if (onGoing == 245) {

            System.exit(245);
        }
        repaint();
    }
}

@Override
public void actionPerformed(ActionEvent e) {
    x = x + velX;
    y = y + velY;
    recY += velY1;
    recX += velX1;
    if (x < 0) {
        velX = 0;
        x = 0;
    }
    if (x > width - 50) {
        velX = 0;
        x = width - 50;
    }
    if (y < 0) {
        velY = 0;
        y = 0;
    }
    if (y > height - 40) {
        velY = 0;
        y = height - 40;
    }
    //Second square
    if (recX < 0) {
        velX1 = 0;
        recX = 0;
    }
    if (recX > width - 50) {
        velX1 = 0;
        recX = width - 50;
    }
    if (recY < 0) {
        velY1 = 0;
        recY = 0;
    }
    if (recY > height - 40) {
        velY1 = 0;
        recY = height - 40;
    }
    repaint();
}

@Override
public void keyPressed(KeyEvent e) {
    int code = e.getKeyCode();
    if (code == KeyEvent.VK_LEFT) {
        velX = -5;
        velY = 0;
    }
    if (code == KeyEvent.VK_UP) {
        velX = 0;
        velY = -5;
    }
    if (code == KeyEvent.VK_RIGHT) {
        velX = 5;
        velY = 0;
    }
    if (code == KeyEvent.VK_DOWN) {
        velX = 0;
        velY = 5;
    }
    //Second Rect
    if (code == KeyEvent.VK_A) {
        velX1 = -5;
        velY1 = 0;
    }
    if (code == KeyEvent.VK_W) {
        velX1 = 0;
        velY1 = -5;
    }
    if (code == KeyEvent.VK_D) {
        velX1 = 5;
        velY1 = 0;
    }
    if (code == KeyEvent.VK_S) {
        velX1 = 0;
        velY1 = 5;
    }
}

@Override
public void keyReleased(KeyEvent e) {
    velX = 0;
    velY = 0;
    velX1 = 0;
    velY1 = 0;
}

public static void main(String[] args) {
    CatchMe main = new CatchMe();
}

@Override
public void keyTyped(KeyEvent e) {
    throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
}
}

Answer 1

@Override
public void keyTyped(KeyEvent e) {

}

Will fix it, you were manually throwing exception when keyTyped is called.

Answer 2

The keyTyped method throws an UnsupportedOperationException because you implemented it this way(or it was automatically generated this way):

@Override
public void keyTyped(KeyEvent e) {
    throw new UnsupportedOperationException("Not supported yet."); //To change body of generated methods, choose Tools | Templates.
}

Whenever a key is typed, this method is called, so it throws an exception.

To fix it, you need to change the body of this method. If you don't want it to do anything, just leave its body empty:

@Override
public void keyTyped(KeyEvent e) {

}

If you want to do something, you should implement this method according to the desired behavior. For example, this implementation prints a message every time a key is typed:

 @Override
 public void keyTyped(KeyEvent e) {
     System.out.println("A key was typed");
 }