Apache Struts 2 Documentation > Home > Guides > Tag Developers Guide > Struts Tags > Tag Reference > Generic Tag Reference > generator |
NOTE: JSP-TAG
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.
Dynamic Attributes Allowed:false |
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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 | |
id | false | false | String | Deprecated. Use 'var' instead | |
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 |
Example One: <pre> Generate a simple iterator <s:generator val="%{'aaa,bbb,ccc,ddd,eee'}"> <s:iterator> <s:property /><br/> </s:iterator> </s:generator> </pre> This generates an iterator and print it out using the iterator tag. Example Two: <pre> 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> </pre> 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 Three: <pre> 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/> <% } %> </pre> This generates an iterator and put it in the PageContext under the key as specified by the var attribute. Example Four: <pre> 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; } }; } ... } </pre> This will generate an iterator with each entries decided by the converter supplied. With this converter, it simply add "converter-" to each entries.