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Java in a Nutshell

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The java.awt.event Package

20.14 java.awt.event.InputEvent (JDK 1.1)

This abstract class serves as the superclass for the raw user input event types MouseEvent and KeyEvent.

Use the inherited getComponent() to determine in which component the event occurred. Use getWhen() to obtain a timestamp for the event. Use getModifiers() to determine which keyboard modifier keys or mouse buttons were down when the event occurred. You can decode the getModifiers() return value using the various _MASK constants defined by this class. The class also defines four convenience methods for determining the state of keyboard modifiers.

In Java 1.1, input events are delivered to the appropriate listener objects before they are delivered to the AWT components themselves. If a listener calls the consume() method of the event, the event is not passed on to the component. For example, if a listener registered on a Button "consumes" a mouse click, it prevents the button itself from responding to that event. You can use isConsumed() to test whether some other listener object has already consumed the event.

public abstract class InputEvent extends ComponentEvent {
    // No Constructor
    // Constants
            public static final int ALT_MASK;
            public static final int BUTTON1_MASK;
            public static final int BUTTON2_MASK;
            public static final int BUTTON3_MASK;
            public static final int CTRL_MASK;
            public static final int META_MASK;
            public static final int SHIFT_MASK;
    // Public Instance Methods
            public void consume();  // Overrides AWTEvent
            public int getModifiers();
            public long getWhen();
            public boolean isAltDown();
            public boolean isConsumed();  // Overrides AWTEvent
            public boolean isControlDown();
            public boolean isMetaDown();
            public boolean isShiftDown();



Extended By:

KeyEvent, MouseEvent

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