Class SortIteratorTag

java.lang.Object
jakarta.servlet.jsp.tagext.TagSupport
jakarta.servlet.jsp.tagext.BodyTagSupport
org.apache.struts2.views.jsp.StrutsBodyTagSupport
org.apache.struts2.views.jsp.iterator.SortIteratorTag
All Implemented Interfaces:
jakarta.servlet.jsp.tagext.BodyTag, jakarta.servlet.jsp.tagext.IterationTag, jakarta.servlet.jsp.tagext.JspTag, jakarta.servlet.jsp.tagext.Tag, Serializable

public class SortIteratorTag extends StrutsBodyTagSupport
NOTE: JSP-TAG

A Tag that sorts a List using a Comparator both passed in as the tag attribute. If 'var' attribute is specified, the sorted list will be placed into the PageContext attribute using the key specified by 'var'. The sorted list will ALWAYS be pushed into the stack and poped at the end of this tag.

  • var (String) - if specified, the sorted iterator will be place with this name under page context
  • source (Object) - the source for the sort to take place (should be iteratable) else JspException will be thrown
  • comparator* (Object) - the comparator used to do sorting (should be a type of Comparator or its decendent) else JspException will be thrown
 

 USAGE 1:
 <s:sort comparator="myComparator" source="myList">
      <s:iterator>
      <!-- do something with each sorted elements -->
      <s:property value="..." />
      </s:iterator>
 </s:sort>

 USAGE 2:
 <s:sort var="mySortedList" comparator="myComparator" source="myList" />

 <%
    Iterator sortedIterator = (Iterator) pageContext.getAttribute("mySortedList");
    for (Iterator i = sortedIterator; i.hasNext(); ) {
      // do something with each of the sorted elements
    }
 %>

 
 
See Also:
  • Field Summary

    Fields inherited from class jakarta.servlet.jsp.tagext.BodyTagSupport

    bodyContent

    Fields inherited from class jakarta.servlet.jsp.tagext.TagSupport

    id, pageContext

    Fields inherited from interface jakarta.servlet.jsp.tagext.BodyTag

    EVAL_BODY_BUFFERED, EVAL_BODY_TAG

    Fields inherited from interface jakarta.servlet.jsp.tagext.IterationTag

    EVAL_BODY_AGAIN

    Fields inherited from interface jakarta.servlet.jsp.tagext.Tag

    EVAL_BODY_INCLUDE, EVAL_PAGE, SKIP_BODY, SKIP_PAGE
  • Constructor Summary

    Constructors
    Constructor
    Description
     
  • Method Summary

    Modifier and Type
    Method
    Description
    protected void
    Provide a mechanism to clear tag state, to handle servlet container JSP tag pooling behaviour with some servers, such as Glassfish.
    int
     
    int
     
    void
    setComparator(String comparator)
     
    void
    setPerformClearTagStateForTagPoolingServers(boolean performClearTagStateForTagPoolingServers)
    Request that the tag state be cleared during StrutsBodyTagSupport.doEndTag() processing, which may help with certain edge cases with tag logic running on servers that implement JSP Tag Pooling.
    void
    setSource(String source)
     
    void
     

    Methods inherited from class jakarta.servlet.jsp.tagext.BodyTagSupport

    doAfterBody, doInitBody, getBodyContent, getPreviousOut, setBodyContent

    Methods inherited from class jakarta.servlet.jsp.tagext.TagSupport

    findAncestorWithClass, getId, getParent, getValue, getValues, removeValue, setId, setPageContext, setParent, setValue

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

    Methods inherited from interface jakarta.servlet.jsp.tagext.Tag

    getParent, setPageContext, setParent
  • Constructor Details

    • SortIteratorTag

      public SortIteratorTag()
  • Method Details

    • setComparator

      public void setComparator(String comparator)
    • setSource

      public void setSource(String source)
    • setVar

      public void setVar(String var)
    • setPerformClearTagStateForTagPoolingServers

      public void setPerformClearTagStateForTagPoolingServers(boolean performClearTagStateForTagPoolingServers)
      Description copied from class: StrutsBodyTagSupport
      Request that the tag state be cleared during StrutsBodyTagSupport.doEndTag() processing, which may help with certain edge cases with tag logic running on servers that implement JSP Tag Pooling. Note: Even though the Tag classes extend this class StrutsBodyTagSupport, and this method StrutsBodyTagSupport.setPerformClearTagStateForTagPoolingServers(boolean) exists in the method hierarchy, the JSP processing requires us to explicitly override it in every Tag class in order for the Tag handler method to be visible to the JSP processing. Defining a setter in the superclass alone is insufficient (results in "Cannot find a setter method for the attribute").

      See StrutsBodyTagSupport.clearTagStateForTagPoolingServers() for additional details. Warning: Setting this value to true may allow for the desired behaviour, but doing so may violate the JSP specification. Set to true at your own risk.

      Overrides:
      setPerformClearTagStateForTagPoolingServers in class StrutsBodyTagSupport
      Parameters:
      performClearTagStateForTagPoolingServers - true if tag state should be cleared, false otherwise.
    • doStartTag

      public int doStartTag() throws jakarta.servlet.jsp.JspException
      Specified by:
      doStartTag in interface jakarta.servlet.jsp.tagext.Tag
      Overrides:
      doStartTag in class jakarta.servlet.jsp.tagext.BodyTagSupport
      Throws:
      jakarta.servlet.jsp.JspException
    • doEndTag

      public int doEndTag() throws jakarta.servlet.jsp.JspException
      Specified by:
      doEndTag in interface jakarta.servlet.jsp.tagext.Tag
      Overrides:
      doEndTag in class StrutsBodyTagSupport
      Throws:
      jakarta.servlet.jsp.JspException
    • clearTagStateForTagPoolingServers

      protected void clearTagStateForTagPoolingServers()
      Description copied from class: StrutsBodyTagSupport
      Provide a mechanism to clear tag state, to handle servlet container JSP tag pooling behaviour with some servers, such as Glassfish.

      Usage: Override this method in descendant classes to clear any state that might cause issues should the servlet container re-use a cached instance of the tag object. If the descendant class does not declare any new field members then it should not be strictly necessary to call this method there. Typically that means calling the ancestor's ComponentTagSupport.clearTagStateForTagPoolingServers() method first, then resetting instance variables at the current level to their default state.

      Note: If the descendant overrides StrutsBodyTagSupport.doEndTag(), and does not call super.doEndTag(), then the descendant should call this method in the descendant doEndTag() method to ensure consistent clearing of tag state.

      Overrides:
      clearTagStateForTagPoolingServers in class StrutsBodyTagSupport