org.apache.struts2.components

Class Set

java.lang.Object

org.apache.struts2.components.Component

org.apache.struts2.components.ContextBean

org.apache.struts2.components.Set

public class Set
extends ContextBean

The set tag assigns a value to a variable in a specified scope. It is useful when you wish to assign a variable to a complex expression and then simply reference that variable each time rather than the complex expression. This is useful in both cases: when the complex expression takes time (performance improvement) or is hard to read (code readability improvement).

If the tag is used with body content, the evaluation of the value parameter is omitted. Instead, the String to which the body evaluates is set as value for the scoped variable.

The scopes available are as follows:

• application - the value will be set in application scope according to servlet spec. using the name as its key
• session - the value will be set in session scope according to servlet spec. using the name as key
• request - the value will be set in request scope according to servlet spec. using the name as key
• page - the value will be set in page scope according to servlet spec. using the name as key
• action - the value will be set in the request scope and Struts' action context using the name as key

NOTE:
If no scope is specified, it will default to action scope.

Parameters

• var* (String): The name of the new variable that is assigned the value of value
• value (Object): The value that is assigned to the variable named name
• scope (String): The scope in which to assign the variable. Can be application, session, request, page, or action. By default it is action.

Examples

 
 <s:set var="personName" value="person.name"/>
 Hello, <s:property value="#personName"/>

 <s:set var="janesName">Jane Doe</s:set>
 <s:property value="#janesName"/>
 
 

Field Summary

Fields

Modifier and Type	Field and Description
protected String	scope
protected String	value

Fields inherited from class org.apache.struts2.components.ContextBean

var

Fields inherited from class org.apache.struts2.components.Component

actionMapper, COMPONENT_STACK, devMode, parameters, stack, standardAttributesMap, throwExceptionOnELFailure

Constructor Summary

Constructors

Constructor and Description
Set(ValueStack stack)

Method Summary

Methods

Modifier and Type	Method and Description
boolean	end(Writer writer, String body) Callback for the end tag of this component.
void	setScope(String scope)
void	setValue(String value)
void	setVar(String var)
boolean	usesBody() Overwrite to set if body should be used.

Methods inherited from class org.apache.struts2.components.ContextBean

getVar, putInContext

Methods inherited from class org.apache.struts2.components.Component

addAllParameters, addParameter, altSyntax, completeExpressionIfAltSyntax, copyParams, determineActionURL, determineNamespace, end, fieldError, findAncestor, findString, findString, findStringIfAltSyntax, findValue, findValue, findValue, getComponentStack, getParameters, getStack, getStandardAttributes, isValidTagAttribute, popComponentStack, setActionMapper, setDevMode, setThrowExceptionsOnELFailure, setUrlHelper, start, stripExpressionIfAltSyntax, toString

Methods inherited from class java.lang.Object

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

Field Detail

scope

protected String scope

value

protected String value

Constructor Detail

Set

public Set(ValueStack stack)

Method Detail

end

public boolean end(Writer writer,
          String body)

Description copied from class: Component

Callback for the end tag of this component. Should the body be evaluated again?
NOTE: will pop component stack.

Overrides:

end in class Component

Parameters:

writer - the output writer.

body - the rendered body.

Returns:

true if the body should be evaluated again

setVar

public void setVar(String var)

Overrides:

setVar in class ContextBean

setScope

public void setScope(String scope)

setValue

public void setValue(String value)

usesBody

public boolean usesBody()

Description copied from class: Component

Overwrite to set if body should be used.

Overrides:

usesBody in class Component

Returns:

always false for this component.