Package org.apache.tapestry5.annotations

# Annotation Type Cached

@Target(METHOD) @Retention(RUNTIME) @Documented @UseWith({COMPONENT,MIXIN,PAGE}) public @interface Cached
Indicates that a method should only be evaluated once per request and the result cached. Further calls to the method during the same request will return the cached result. However, if the method's component occurs more than once within an enclosing component, the cached results will be distinct for each occurrence. This annotation is commonly used on getters for component properties:

     @Cached
     Date getNow() {
         new Date();
     }

You may not apply @Cached to void methods or methods with parameters. Note that this annotation is inheritance-safe; if a subclass calls a superclass method that has @Cached then the value the subclass method gets is the cached value. The watch parameter can be passed a binding expression which will be evaluated each time the method is called. The method will then only be executed the first time it is called and after that only when the value of the binding changes. This can be used, for instance, to have the method only evaluated once per iteration of a loop by setting watch to the value or index of the loop.

- ## Optional Element Summary

  Optional Elements
  Modifier and Type
  Optional Element
  Description
  `String`
  `watch`
  The optional binding to watch (default binding prefix is "prop").

- ## Element Details

  - ### watch

    String watch
    The optional binding to watch (default binding prefix is "prop").
    Default:
      ""