org.apache.struts2.views.jsp

## Class BeanTag

- java.lang.Object
- - javax.servlet.jsp.tagext.TagSupport
  - - javax.servlet.jsp.tagext.BodyTagSupport
    - - org.apache.struts2.views.jsp.StrutsBodyTagSupport
      - - org.apache.struts2.views.jsp.ComponentTagSupport
        - - org.apache.struts2.views.jsp.ContextBeanTag
          - - org.apache.struts2.views.jsp.BeanTag

- 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 BeanTag
      extends ContextBeanTag

  See Also:
    `Bean`, Serialized Form

- - ### Field Summary

    Fields
    Modifier and Type | Field and Description
    --- | ---
    `protected static org.apache.logging.log4j.Logger` | `LOG`
    `protected String` | `name`

    - ### Fields inherited from class org.apache.struts2.views.jsp.ComponentTagSupport

      `component`

    - ### 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
    `BeanTag()`

  - ### 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.
    `Component` | `getBean(ValueStack stack, javax.servlet.http.HttpServletRequest req, javax.servlet.http.HttpServletResponse res)`
    `protected void` | `populateParams()` Define method to populate component state based on the Tag parameters.
    `void` | `setName(String name)`
    `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.

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

      `setVar`

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

      `doEndTag, doStartTag, getComponent, populatePerformClearTagStateForTagPoolingServersParam`

    - ### 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`

- - ### Field Detail

    - #### LOG

          protected static org.apache.logging.log4j.Logger LOG

    - #### name

          protected String name

  - ### Constructor Detail

    - #### BeanTag

          public BeanTag()

  - ### Method Detail

    - #### getBean

          public Component getBean(ValueStack stack,
                                   javax.servlet.http.HttpServletRequest req,
                                   javax.servlet.http.HttpServletResponse res)

      Specified by:
        `getBean` in class `ComponentTagSupport`

    - #### populateParams

          protected void populateParams()

      Description copied from class: `ComponentTagSupport`
      Define method to populate component state based on the Tag parameters. Descendants should override this method for custom behaviour, but should always call the ancestor method when doing so.
      Overrides:
        `populateParams` in class `ContextBeanTag`

    - #### setName

          public void setName(String name)

    - #### 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 `ContextBeanTag`
      Parameters:
        `performClearTagStateForTagPoolingServers` - true if tag state should be cleared, false otherwise.

    - #### 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 `ContextBeanTag`

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