LazyCommands are an extension of ActionCommand that delay initialization until the first time they are invoked.  This is particularly useful for commands that may be used infrequently and that have high resource cost.

The LazyCommand class defines two abstract  methods, build() and lazyExecute().  The first time the command is executed, build will be called followed by lazyExecute.  Subsequent command invocations will only call lazyExecute. 

Example

   public class MyLazyCommand
   extends LazyCommand
   {
      private BigWidget widget;
      
      public MyLazyCommand()
      {
      	super("my-lazy-command");
      }
      
      public void build()
      {
        // lazily build the widget
      	widget = new BigWidget();
      }   		
   
      public void lazyExecute()
      {
        // and now we use it
      	widget.doSomething();
      }
   }