Java 2入门经典：JDK 5 SOLUTION 这本书综合介绍了使用J2SE(Java 2 Standard Edition)5．0或更高版本开发动态程序的过程

				// Defines application wide constants
				package Constants;
				import java.awt.Color;
				
				public class SketcherConstants { 
				  // Element type definitions
				  public final static int LINE      = 101;
				  public final static int RECTANGLE = 102;
				  public final static int CIRCLE    = 103;
				  public final static int CURVE     = 104;
				  public final static int ELLIPSE   = 106;
				
				  // Initial conditions
				  public final static int DEFAULT_ELEMENT_TYPE = LINE;
				  public final static Color DEFAULT_ELEMENT_COLOR = Color.BLUE;
				}