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# generator

Please make sure you have read the Tag Syntax document and understand how tag attribute syntax works.

## Description

Generate an iterator based on the val attribute supplied.

> NOTE: The generated iterator will ALWAYS be pushed into the top of the stack, and poped at the end of the tag.

Generate an iterator for a iterable source.

## Attributes

#### Dynamic Attributes Allowed: false
#### Name | #### Required | #### Default | #### Evaluated | #### Type | #### Description
--- | --- | --- | --- | --- | ---
converter | false |  | false | org.apache.struts2.util.IteratorGenerator.Converter | The converter to convert the String entry parsed from val into an object
count | false |  | false | Integer | The max number entries to be in the iterator
separator | true |  | false | String | The separator to be used in separating the val into entries of the iterator
val | true |  | false | String | The source to be parsed into an iterator
var | false |  | false | String | The name to store the resultant iterator into page context, if such name is supplied

## Examples

Example 1: generate a simple iterator

    <s:generator val="%{'aaa,bbb,ccc,ddd,eee'}">
     <s:iterator>
         <s:property /><br/>
     </s:iterator>
    </s:generator>

This generates an iterator and print it out using the iterator tag.

Example 2: generate an iterator with count attribute

    <s:generator val="%{'aaa,bbb,ccc,ddd,eee'}" count="3">
     <s:iterator>
         <s:property /><br/>
     </s:iterator>
    </s:generator>

This generates an iterator, but only 3 entries will be available in the iterator generated, namely aaa, bbb and ccc respectively because count attribute is set to 3.

Example 3: generate an iterator with var attribute

    <s:generator val="%{'aaa,bbb,ccc,ddd,eee'}" count="4" separator="," var="myAtt" />
    <%
     Iterator i = (Iterator) pageContext.getAttribute("myAtt");
     while(i.hasNext()) {
         String s = (String) i.next(); %>
         <%=s%> <br/>
    <%    }
    %>

This generates an iterator and put it in the PageContext under the key as specified by the var attribute.

Example 4: generate an iterator with comparator attribute

    <s:generator val="%{'aaa,bbb,ccc,ddd,eee'}" converter="%{myConverter}">
     <s:iterator>
         <s:property /><br/>
     </s:iterator>
    </s:generator>

    public class GeneratorTagAction extends ActionSupport {

      ....

      public Converter getMyConverter() {
         return new Converter() {
             public Object convert(String value) throws Exception {
                 return "converter-"+value;
             }
         };
      }

      ...

    }

This will generate an iterator with each entries decided by the converter supplied. With this converter, it simply add “converter-“ to each entries.