关于KeyListener的一个问题~
我想写一个可以类似坦克大战的游戏，不过是可以两个人一起玩的。
两个人分别用wasd和上下左右键控制。
但是运行之后发现在同一时刻好像只有一个键能管用，比如我按了上，再按w，那么上就不再能操纵坦克了。
怎么办呢~~
新手啊，求帮助~~
谢谢大家~
[解决办法]
当第一个键按下后，再感应第二个键是可以的，你可以试下：

import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.awt.event.KeyEvent;
import java.awt.event.KeyListener;

import javax.swing.JButton;
import javax.swing.JComponent;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JTextArea;
import javax.swing.JTextField;

public class KeyEventDemo extends JPanel implements KeyListener, ActionListener {
  JTextArea displayArea;

  JTextField typingArea;

  static final String newline = "\n";

  public KeyEventDemo() {
    super(new BorderLayout());

    JButton button = new JButton("Clear");
    button.addActionListener(this);

    typingArea = new JTextField(20);
    typingArea.addKeyListener(this);

    //Uncomment this if you wish to turn off focus
    //traversal. The focus subsystem consumes
    //focus traversal keys, such as Tab and Shift Tab.
    //If you uncomment the following line of code, this
    //disables focus traversal and the Tab events will
    //become available to the key event listener.
    //typingArea.setFocusTraversalKeysEnabled(false);

    displayArea = new JTextArea();
    displayArea.setEditable(false);
    JScrollPane scrollPane = new JScrollPane(displayArea);
    scrollPane.setPreferredSize(new Dimension(375, 125));

    add(typingArea, BorderLayout.PAGE_START);
    add(scrollPane, BorderLayout.CENTER);
    add(button, BorderLayout.PAGE_END);
  }

  /** Handle the key typed event from the text field. */
  public void keyTyped(KeyEvent e) {
    displayInfo(e, "KEY TYPED: ");
  }

  /** Handle the key pressed event from the text field. */
  public void keyPressed(KeyEvent e) {
    displayInfo(e, "KEY PRESSED: ");
  }

  /** Handle the key released event from the text field. */
  public void keyReleased(KeyEvent e) {
    displayInfo(e, "KEY RELEASED: ");
  }

  /** Handle the button click. */
  public void actionPerformed(ActionEvent e) { 
 
    //Clear the text components.
    displayArea.setText("");
    typingArea.setText("");

    //Return the focus to the typing area.
    typingArea.requestFocusInWindow();
  }

  /*
   * We have to jump through some hoops to avoid trying to print non-printing
   * characters such as Shift. (Not only do they not print, but if you put
   * them in a String, the characters afterward won't show up in the text
   * area.)
   */
  protected void displayInfo(KeyEvent e, String s) {
    String keyString, modString, tmpString, actionString, locationString;

    //You should only rely on the key char if the event
    //is a key typed event.
    int id = e.getID();
    if (id == KeyEvent.KEY_TYPED) {
      char c = e.getKeyChar();
      keyString = "key character = '" + c + "'";
    } else {
      int keyCode = e.getKeyCode();
      keyString = "key code = " + keyCode + " ("
          + KeyEvent.getKeyText(keyCode) + ")";
    }

    int modifiers = e.getModifiersEx();
    modString = "modifiers = " + modifiers;
    tmpString = KeyEvent.getModifiersExText(modifiers);
    if (tmpString.length() > 0) {
      modString += " (" + tmpString + ")";
    } else {
      modString += " (no modifiers)";
    }

    actionString = "action key? ";
    if (e.isActionKey()) {
      actionString += "YES";
    } else {
      actionString += "NO";
    }

    locationString = "key location: ";
    int location = e.getKeyLocation();
    if (location == KeyEvent.KEY_LOCATION_STANDARD) {
      locationString += "standard";
    } else if (location == KeyEvent.KEY_LOCATION_LEFT) {
      locationString += "left";
    } else if (location == KeyEvent.KEY_LOCATION_RIGHT) {
      locationString += "right";
    } else if (location == KeyEvent.KEY_LOCATION_NUMPAD) {
      locationString += "numpad"; 
 
    } else { // (location == KeyEvent.KEY_LOCATION_UNKNOWN)
      locationString += "unknown";
    }

    displayArea.append(s + newline + "    " + keyString + newline + "    "
        + modString + newline + "    " + actionString + newline
        + "    " + locationString + newline);
    displayArea.setCaretPosition(displayArea.getDocument().getLength());
  }

  /**
   * Create the GUI and show it. For thread safety, this method should be
   * invoked from the event-dispatching thread.
   */
  private static void createAndShowGUI() {
    //Make sure we have nice window decorations.
    JFrame.setDefaultLookAndFeelDecorated(true);

    //Create and set up the window.
    JFrame frame = new JFrame("KeyEventDemo");
    frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);

    //Create and set up the content pane.
    JComponent newContentPane = new KeyEventDemo();
    newContentPane.setOpaque(true); //content panes must be opaque
    frame.setContentPane(newContentPane);

    //Display the window.
    frame.pack();
    frame.setVisible(true);
  }

  public static void main(String[] args) {
    //Schedule a job for the event-dispatching thread:
    //creating and showing this application's GUI.
    javax.swing.SwingUtilities.invokeLater(new Runnable() {
      public void run() {
        createAndShowGUI();
      }
    });
  }
}