org.apache.taglibs.session
Class ExistsAttributeTag

java.lang.Object
  |
  +--javax.servlet.jsp.tagext.TagSupport
        |
        +--org.apache.taglibs.session.ExistsAttributeTag

All Implemented Interfaces:

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 HttpSession 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.session.ExistsAttributeTag</tagclass>
 <bodycontent>JSP</bodycontent>
 <info>Includes the body of the tag if the session 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

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

id, pageContext

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 session 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

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 session attribute exists.

Overrides:

doStartTag in class javax.servlet.jsp.tagext.TagSupport

Returns:

SKIP_BODY if existsAttribute doesn't match value, EVAL_BODY_include if existsAttribute matches value

setName

public final void setName(java.lang.String str)

Set the required tag attribute name.

Parameters:

String - name of session attribute

setValue

public final void setValue(boolean value)

Set the optional tag attribute value to true or false.

Parameters:

boolean - true or false