[Chapter 18] 18.21 java.awt.EventQueue (JDK 1.1)

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| Chapter 18 The java.awt Package |

## 18.21 java.awt.EventQueue (JDK 1.1)

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This class implements an event queue for AWT events in Java 1.1. When an `EventQueue` is created, a new thread is automatically created and started to remove events from the front of the queue and dispatch them to the appropriate component. It is this thread, created by the `EventQueue`, that notifies event listeners and executes most of the code in a typical GUI-driven application.

An application can create and use its own private `EventQueue`, but all AWT events are placed on and dispatched from a single system `EventQueue`. Use the `getSystemEventQueue()` method of the `Toolkit` class to get the system `EventQueue` object.

`getNextEvent()` removes and returns the event at the front of the queue. It blocks if there are no events in the queue. `peekEvent()` returns the event at the front of the queue without removing it from the queue. Passed an optional `AWTEvent` `id` field, it returns the first event of the specified type. Finally, `postEvent()` places a new event on the end of the event queue.

Most applications do not need to use the `EventQueue` class at all; they can simply rely on the system to dispatch events automatically.

    public class EventQueue extends Object {
        // Public Constructor
                public EventQueue();
        // Public Instance Methods
                public synchronized AWTEvent getNextEvent() throws InterruptedException;
                public synchronized AWTEvent peekEvent();
                public synchronized AWTEvent peekEvent(int id);
                public synchronized void postEvent(AWTEvent theEvent);
    }

### Returned By:

`Toolkit.getSystemEventQueue(), Toolkit.getSystemEventQueueImpl()`

java.awt.Event (JDK 1.0) |  | java.awt.FileDialog (JDK 1.0)