我在下面发布的示例代码显示了两个类。一个实现 KeyListener,另一个实现 Runnable,并在每 20 毫秒休眠一次的无限循环中运行。当一个键被按下时,keyChar,它是一个int的形式,被用作一个索引,设置一个布尔数组的索引是真还是假,表示该键被按下与否。同时,进程循环在键数组中搜索其真值或假值,并将真值设置为假,然后打印出字符。我的问题是我是否需要使用锁来使用同步来访问 charArray,因为它在两个线程中使用:进程线程和键侦听器线程。
示例代码:
import java.awt.Component;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;
public class Input implements KeyListener {
public boolean[] charArray;
public Input(Component component) {
charArray = new boolean[127];
component.addKeyListener(this);
}
@Override
public void keyPressed(KeyEvent e) {
(possible synchronization with a lock?)
int keyChar = e.getKeyChar();
if (keyChar == 27 || keyChar == 9 || keyChar == 10 || keyChar == 127) //useless keys like del, tab, esc, etc..
keyChar = 65535;
if (keyChar < 65535) //65535 represents no true char value
charArray[keyChar] = true;
}
@Override
public void keyReleased(KeyEvent e) {
}
@Override
public void keyTyped(KeyEvent e) {
}
}
import java.awt.Dimension;
import javax.swing.JFrame;
@SuppressWarnings("serial")
public class Process extends JFrame implements Runnable {
private boolean running;
private Input input;
public Process() {
running = false;
input = new Input(this);
setTitle("Keyboard Test");
setSize(new Dimension(200, 200));
toFront();
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
setVisible(true);
}
/**
* @param args
*/
public static void main(String[] args) {
new Process().startThread();
}
public synchronized void startThread() {
running = true;
new Thread(this).start();
}
@Override
public void run() {
while (running) {
(possible synchronization with a lock?)
for (int i = 0; i < input.charArray.length; i++) {
if (input.charArray[i] == true) {
input.charArray[i] = false;
System.out.println((char) i);
}
}
try {
Thread.sleep(20);
} catch (InterruptedException e) {
}
}
}
}