Package org.apache.tapestry5.annotations

## Annotation Type RequestParameter

-     @Target(PARAMETER)
      @Retention(RUNTIME)
      @Documented
      @UseWith({COMPONENT,MIXIN,PAGE})
      public @interface RequestParameter

  Annotation that may be placed on parameters of event handler methods. Annotated parameters will be extracted from the request, then converted to the type of the parameter. Such parameters are separate from ordinary context parameters (extracted from the Request path). Typically, this is used when client-side JavaScript adds a query parameter to a request to communicate some information from the client side to the server side. Individual fields may also be directly mapped to query parameters using the `ActivationRequestParameter` annotation.
  Since:
    5.2.0
  See Also:
    `OnEventWorker`

- - ### Required Element Summary

    Required Elements
    Modifier and Type | Required Element | Description
    --- | --- | ---
    `java.lang.String` | `value` | The name of the query parameter to extract from the request.

  - ### Optional Element Summary

    Optional Elements
    Modifier and Type | Optional Element | Description
    --- | --- | ---
    `boolean` | `allowBlank` | If false (the default), then an exception is thrown when the query parameter is read, if it is blank (null or an empty string).

- - ### Element Detail

    - #### value

          java.lang.String value

      The name of the query parameter to extract from the request.

  - - #### allowBlank

          boolean allowBlank

      If false (the default), then an exception is thrown when the query parameter is read, if it is blank (null or an empty string). If true, then blank values are allowed and will be passed through the appropriate `ValueEncoder` implementation.
      Default:
        false