Package net.java.sezpoz

Support for declaring, creating, and inspecting indices of annotated Java elements.

See:
Description

Class Summary

Index<A extends Annotation,I>	Represents an index of a single annotation.
IndexItem<A extends Annotation,I>	One index item.

Error Summary

IndexError

Error thrown when loading all or part of an index fails.

Annotation Types Summary

Indexable

Marker for an annotation type which can be indexed.

Package net.java.sezpoz Description

Support for declaring, creating, and inspecting indices of annotated Java elements.

For example, to permit registration of simple menu items, while making it possible to prepare a menu without loading any of them until they are actually selected:

 @Target({ElementType.TYPE, ElementType.METHOD, ElementType.FIELD})
 @Retention(RetentionPolicy.SOURCE)
 @Indexable(type=ActionListener.class)
 public @interface MenuItem {
     String menuName();
     String itemName();
     String iconPath() default "";
 }
 

A concrete registration might look like:

 @MenuItem(menuName="File", itemName="Print", iconPath=".../print.png")
 public class PrintAction extends AbstractAction {
     public void actionPerformed(ActionEvent e) {...}
 }
 

Alternatively:

 public class Actions {
     @MenuItem(menuName="File", itemName="Print")
     public static Action print() {...}
 }
 

or even:

 public class Actions {
     @MenuItem(menuName="File", itemName="Print")
     public static final Action PRINT = ...;
 }
 

To create the index on JDK 6, just compile your sources normally with javac. If using JDK 5, simply run apt instead of/in addition to javac. (The processor is in the same JAR as this API and should be autodetected.)

Usage is then simple:

 for (final IndexItem<MenuItem,ActionListener> item :
         Index.load(MenuItem.class, ActionListener.class)) {
     JMenu menu = new JMenu(item.annotation().menuName());
     JMenuItem menuitem = new JMenuItem(item.annotation().itemName());
     String icon = item.annotation().iconPath();
     if (!icon.equals("")) {
          menuitem.setIcon(new ImageIcon(icon));
     }
     menuitem.addActionListener(new ActionListener() {
         public void actionPerformed(ActionEvent e) {
             try {
                 item.instance().actionPerformed(e);
             } catch (InstantiationException x) {
                 x.printStackTrace();
             }
         }
     });
 }
 

If you want to see what is getting loaded and when, configure java.util.logging so that the logger named net.java.sezpoz is visible at Level.FINER or above.