netui-data:callPageFlow Tag

<netui-data:callPageFlow> Tag

This tag calls a method on the Controller file (= JPF file) in the same directory as the JSP page.

Syntax

<netui-data:callPageFlow
    [failOnError="boolean_failOnError"]
    method="string_method"
    [object="string_or_expression_object"]
    [resultId="string_resultId"] />

Description

This tag calls a method on the Controller file (= JPF file) in the same directory as the JSP page. If no Controller file is found, an ObjectNotFoundException is thrown and the tag execution fails. Any return value is stored in the {pageContext...} data binding context object under the attribute specified by the resultId attribute.

For example, if you call the hello method with the following <netui-data:callPageFlow> tag...

    <netui-data:callPageFlow
          method="hello" 
          resultId="helloMessage" 
          />

...the result of the call is stored in the {pageContext...} data binding context under the attribute helloMessage.

The result can be retrieved with the data binding expression {pageContext.helloMessage}

   <netui:label value="{pageContext.helloMessage}"/>

In a scriptlet, the result can be retrieved by calling the getAttribute() method on the javax.servlet.jsp.PageContext object:

    <%= pageContext.getAttribute("helloMessage") %>

Note that only synchronous methods can be called with <netui-data:callPageFlow>. For handling asynchronous methods see the help topic Calling Web Services and Custom Java Controls From A Page Flow

Attributes

failOnError

Boolean. If set to true, any errors occuring while invoking the control method will be be reported in-line on the JSP page.

Required	Supports runtime expression evaluation	Data bindable
No	No	No

method

The name of the method to invoke

Required	Supports runtime expression evaluation	Data bindable
Yes	No	No

object

A string or data binding expression that names the class on which to call a method.

Required	Supports runtime expression evaluation	Data bindable
No	No	Read Only

resultId

The data returned by the method is loaded into the PageContext object, under this property name.

Required	Supports runtime expression evaluation	Data bindable
No	No	No

Sample

In the following sample, the <netui-data:callPageFlow> tag calls the sumCartItems method on the Controller file. The <netui:label> tag accesses the result through the {pageContext...} data binding context.

     <netui-data:callPageFlow method="sumCartItems" resultId="cartSum">
          <netui-data:methodParameter value="{pageFlow.cart.lineItemList}"/>
      </netui-data:callPageFlow>
      ...
      <netui:label value="{pageContext.cartSum}"/>

Code Sample