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Java in a Nutshell

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The java.awt Package

18.39 java.awt.MediaTracker (JDK 1.0)

This class provides a very convenient way to asynchronously load and keep track of the status of any number of Image objects. You can use it to load one or more images and to wait until those images have been completely loaded and are ready to be used.

The addImage() method registers an image to be loaded and tracked and assigns it a specified identifier value. waitForID() loads all images that have been assigned the specified identifier and returns when they have all finished loading or it has received an error. isErrorAny() and isErrorID() check whether any errors have occurred while loading images. statusAll() and statusID() return the status of all images or of all images with the specified identifier. The return value of these two methods is one of the defined constants.

public class MediaTracker extends Object implements Serializable {
    // Public Constructor
            public MediaTracker(Component comp);
    // Constants
            public static final int ABORTED;
            public static final int COMPLETE;
            public static final int ERRORED;
            public static final int LOADING;
    // Public Instance Methods
            public void addImage(Image image, int id);
            public synchronized void addImage(Image image, int id, int w, int h);
            public boolean checkAll();
            public boolean checkAll(boolean load);
            public boolean checkID(int id);
            public boolean checkID(int id, boolean load);
            public synchronized Object[] getErrorsAny();
            public synchronized Object[] getErrorsID(int id);
            public synchronized boolean isErrorAny();
            public synchronized boolean isErrorID(int id);
        1.1  public synchronized void removeImage(Image image);
        1.1  public synchronized void removeImage(Image image, int id);
        1.1  public synchronized void removeImage(Image image, int id, int width, int height);
            public int statusAll(boolean load);
            public int statusID(int id, boolean load);
            public void waitForAll() throws InterruptedException;
            public synchronized boolean waitForAll(long ms) throws InterruptedException;
            public void waitForID(int id) throws InterruptedException;
            public synchronized boolean waitForID(int id, long ms) throws InterruptedException;

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