imagebean4beaninfo.java

程序练习中包括书中实例程序代码和练习中要用到的代码,是压缩文件

package examples.beans;
import java.beans.*;
import java.lang.reflect.Method;
/** The class contains information about the ImageBean4
  * class in a format that is understood by JavaBean
  * builder programs like Sun's BeanBox
  */
public class ImageBean4BeanInfo extends SimpleBeanInfo {
   /** Create an array of PropertyDescriptor objects
     * representing each of the class's properties
     * @return The array of PropertyDescriptor objects
     */
   public PropertyDescriptor[] getPropertyDescriptors() {
      PropertyDescriptor[] pds = null;
      try {
         pds = new PropertyDescriptor[] {
            new PropertyDescriptor( "fillColor",
                                    ImageBean4.class ),
            new PropertyDescriptor( "fileName",
                                    ImageBean4.class ),
            new PropertyDescriptor( "scaling",
                                    ImageBean4.class ),
            new PropertyDescriptor( "preferredSize",
                                    ImageBean4.class,
                                    "getPreferredSize",
                                    null )
         };
         pds[0].setShortDescription(
            "The fill color around the image" );
         pds[1].setShortDescription(
            "The file containing the image" );
         pds[2].setShortDescription(
            "How the image should be drawn" );
         pds[3].setShortDescription(
            "The preferred size of the panel" );
         // all properties of this bean are bound
         for ( int i=0; i<pds.length; i++ ) {
            pds[i].setBound( true );
         }
         pds[2].setPropertyEditorClass(
                            ScalingEditor.class );
      } catch( IntrospectionException ix ) {
         System.out.println( ix );
         return super.getPropertyDescriptors();
      }
      return pds;
   }
   /** Indicate that the fileName property is the
     * default property to be updated by returning
     * its index in the PropertyDescriptor array
     * obtained from the method
     * getPropertyDescriptors
     * @return The index of the fileName array
     *         element
     */
   public int getDefaultPropertyIndex() {
      return 1;   // the filename property index
   }
}