myobserver.java

learning java的源代码。书中每个实例都有相关的代码example。

//file: MyObserver.java
import java.awt.*;
import java.awt.image.*;

class MyObserver implements ImageObserver {

  public boolean imageUpdate( Image image, int flags, int x, int y,
                              int width, int height) {

    if ( (flags & HEIGHT) !=0 )
      System.out.println("Image height = " + height );

    if ( (flags & WIDTH ) !=0 )
      System.out.println("Image width = " + width );

    if ( (flags & FRAMEBITS) != 0 )
      System.out.println("Another frame finished.");

    if ( (flags & SOMEBITS) != 0 )
      System.out.println("Image section :"
             + new Rectangle( x, y, width, height ) );

    if ( (flags & ALLBITS) != 0 ) {
      System.out.println("Image finished!");
      return false;
    }

    if ( (flags & ABORT) != 0 ) {
      System.out.println("Image load aborted...");
      return false;
    }
    return true;
  }
}