org.apache.taglibs.request
Class ExistsAttributeTag

java.lang.Object
  extended byjavax.servlet.jsp.tagext.TagSupport
      extended byorg.apache.taglibs.request.ExistsAttributeTag
All Implemented Interfaces:
javax.servlet.jsp.tagext.IterationTag, java.io.Serializable, javax.servlet.jsp.tagext.Tag

public class ExistsAttributeTag
extends javax.servlet.jsp.tagext.TagSupport

JSP Tag existsattribute, used to determine if an HttpServletRequest attribute exists.

Includes the body of the tag if the attribute exists.

You can set the optional tag attribute value to true or false. The body of the tag is included if existsattribute matches the value.

JSP Tag Lib Descriptor

 <name>existsattribute</name>
 <tagclass>org.apache.taglibs.request.ExistsAttributeTag</tagclass>
 <bodycontent>JSP</bodycontent>
 <info>Includes the body of the tag if the request attribute exists.</info>
   <attribute>
     <name>name</name>
     <required>true</required>
     <rtexprvalue>false</rtexprvalue>
   </attribute>
   <attribute>
     <name>value</name>
     <required>false</required>
     <rtexprvalue>false</rtexprvalue>
   </attribute>
 

Author:
Glenn Nielsen
See Also:
Serialized Form

Field Summary
 
Fields inherited from class javax.servlet.jsp.tagext.TagSupport
id, pageContext
 
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
ExistsAttributeTag()
           
 
Method Summary
 int doStartTag()
          Includes the body of the tag if the request attribute exists.
 void setName(java.lang.String str)
          Set the required tag attribute name.
 void setValue(boolean value)
          Set the optional tag attribute value to true or false.
 
Methods inherited from class javax.servlet.jsp.tagext.TagSupport
doAfterBody, doEndTag, findAncestorWithClass, getId, getParent, getValue, getValues, release, removeValue, setId, setPageContext, setParent, setValue
 
Methods inherited from class java.lang.Object
clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
 

Constructor Detail

ExistsAttributeTag

public ExistsAttributeTag()
Method Detail

doStartTag

public final int doStartTag()
                     throws javax.servlet.jsp.JspException
Includes the body of the tag if the request attribute exists.

Returns:
SKIP_BODY if existsattribute doesn't match value, EVAL_BODY_include if existsattribute matches value
Throws:
javax.servlet.jsp.JspException

setName

public final void setName(java.lang.String str)
Set the required tag attribute name.


setValue

public final void setValue(boolean value)
Set the optional tag attribute value to true or false.



Copyright ? 2000-2004 The Apache Software Foundation. All Rights Reserved.