org.apache.struts2.views.jsp.iterator

## Class SortIteratorTag

- java.lang.Object
- - javax.servlet.jsp.tagext.TagSupport
  - - javax.servlet.jsp.tagext.BodyTagSupport
    - - org.apache.struts2.views.jsp.StrutsBodyTagSupport
      - - org.apache.struts2.views.jsp.iterator.SortIteratorTag

- All Implemented Interfaces:
    Serializable, javax.servlet.jsp.tagext.BodyTag, javax.servlet.jsp.tagext.IterationTag, javax.servlet.jsp.tagext.JspTag, javax.servlet.jsp.tagext.Tag

      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:
    `{@literal @}s.tag name="sort" tld-body-content="JSP" description="Sort a List using a Comparator both passed in as the tag attribute."`, Serialized Form

- - ### Field Summary

    - ### Fields inherited from class javax.servlet.jsp.tagext.BodyTagSupport

      `bodyContent`

    - ### Fields inherited from class javax.servlet.jsp.tagext.TagSupport

      `id, pageContext`

    - ### Fields inherited from interface javax.servlet.jsp.tagext.BodyTag

      `EVAL_BODY_BUFFERED, EVAL_BODY_TAG`

    - ### Fields inherited from interface javax.servlet.jsp.tagext.IterationTag

      `EVAL_BODY_AGAIN`

    - ### Fields inherited from interface javax.servlet.jsp.tagext.Tag

      `EVAL_BODY_INCLUDE, EVAL_PAGE, SKIP_BODY, SKIP_PAGE`

  - ### Constructor Summary

    Constructors
    Constructor and Description
    `SortIteratorTag()`

  - ### Method Summary

    All Methods Instance Methods Concrete Methods
    Modifier and Type | Method and Description
    --- | ---
    `protected void` | `clearTagStateForTagPoolingServers()` Provide a mechanism to clear tag state, to handle servlet container JSP tag pooling behaviour with some servers, such as Glassfish.
    `int` | `doEndTag()`
    `int` | `doStartTag()`
    `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` | `setVar(String var)`

    - ### Methods inherited from class org.apache.struts2.views.jsp.StrutsBodyTagSupport

      `findString, findValue, findValue, getBody, getPerformClearTagStateForTagPoolingServers, getStack, release, toString`

    - ### Methods inherited from class javax.servlet.jsp.tagext.BodyTagSupport

      `doAfterBody, doInitBody, getBodyContent, getPreviousOut, setBodyContent`

    - ### Methods inherited from class javax.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 javax.servlet.jsp.tagext.Tag

      `getParent, setPageContext, setParent`

- - ### Constructor Detail

    - #### SortIteratorTag

          public SortIteratorTag()

  - ### Method Detail

    - #### 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 javax.servlet.jsp.JspException

      Specified by:
        `doStartTag` in interface `javax.servlet.jsp.tagext.Tag`
      Overrides:
        `doStartTag` in class `javax.servlet.jsp.tagext.BodyTagSupport`
      Throws:
        `javax.servlet.jsp.JspException`

    - #### doEndTag

          public int doEndTag()
                       throws javax.servlet.jsp.JspException

      Specified by:
        `doEndTag` in interface `javax.servlet.jsp.tagext.Tag`
      Overrides:
        `doEndTag` in class `StrutsBodyTagSupport`
      Throws:
        `javax.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`

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