/*
* $Id: Set.java 651946 2008-04-27 13:41:38Z apetrelli $
*
* Licensed to the Apache Software Foundation (ASF) under one
* or more contributor license agreements. See the NOTICE file
* distributed with this work for additional information
* regarding copyright ownership. The ASF licenses this file
* to you under the Apache License, Version 2.0 (the
* "License"); you may not use this file except in compliance
* with the License. You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing,
* software distributed under the License is distributed on an
* "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
* KIND, either express or implied. See the License for the
* specific language governing permissions and limitations
* under the License.
*/
package org.apache.struts2.components;
import java.io.Writer;
import org.apache.struts2.views.annotations.StrutsTag;
import org.apache.struts2.views.annotations.StrutsTagAttribute;
import com.opensymphony.xwork2.util.ValueStack;
/**
* <!-- START SNIPPET: javadoc -->
* <p>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).</p>
* <p>If the tag is used with body content, the evaluation of the value parameter is omitted. Instead, the String to
* which the body eveluates is set as value for the scoped variable.</p>
*
* The scopes available are as follows :-
* <ul>
* <li>application - the value will be set in application scope according to servlet spec. using the name as its key</li>
* <li>session - the value will be set in session scope according to servlet spec. using the name as key </li>
* <li>request - the value will be set in request scope according to servlet spec. using the name as key </li>
* <li>page - the value will be set in page scope according to servlet sepc. using the name as key</li>
* <li>action - the value will be set in the request scope and Struts' action context using the name as key</li>
* </ul>
*
* NOTE:<p/>
* If no scope is specified, it will default to action scope.
*
* <!-- END SNIPPET: javadoc -->
*
* <p/> <b>Parameters</b>
*
* <!-- START SNIPPET: params -->
*
* <ul>
*
* <li>name* (String): The name of the new variable that is assigned the value of <i>value</i></li>
*
* <li>value (Object): The value that is assigned to the variable named <i>name</i></li>
*
* <li>scope (String): The scope in which to assign the variable. Can be <b>application</b>, <b>session</b>,
* <b>request</b>, <b>page</b>, or <b>action</b>. By default it is <b>action</b>.</li>
*
* </ul>
*
* <!-- END SNIPPET: params -->
*
* <p/> <b>Examples</b>
*
* <pre>
* <!-- START SNIPPET: example -->
* <s:set name="personName" value="person.name"/>
* Hello, <s:property value="#personName"/>. How are you?
* <!-- END SNIPPET: example -->
* </pre>
*
*/
@StrutsTag(name="set", tldBodyContent="JSP", tldTagClass="org.apache.struts2.views.jsp.SetTag", description="Assigns a value to a variable in a specified scope")
public class Set extends ContextBean {
protected String scope;
protected String value;
public Set(ValueStack stack) {
super(stack);
}
public boolean end(Writer writer, String body) {
ValueStack stack = getStack();
Object o;
if (value == null) {
if (body != null && !body.equals("")) {
o = body;
} else {
o = findValue("top");
}
} else {
o = findValue(value);
}
body="";
if ("application".equalsIgnoreCase(scope)) {
stack.setValue("#application['" + getVar() + "']", o);
} else if ("session".equalsIgnoreCase(scope)) {
stack.setValue("#session['" + getVar() + "']", o);
} else if ("request".equalsIgnoreCase(scope)) {
stack.setValue("#request['" + getVar() + "']", o);
} else if ("page".equalsIgnoreCase(scope)) {
stack.setValue("#attr['" + getVar() + "']", o, false);
} else {
stack.getContext().put(getVar(), o);
stack.setValue("#attr['" + getVar() + "']", o, false);
}
return super.end(writer, body);
}
/*
* TODO: set required=true when 'id' is dropped after 2.1
*/
@StrutsTagAttribute(description="Name used to reference the value pushed into the Value Stack")
public void setVar(String var) {
super.setVar(var);
}
@StrutsTagAttribute(description="Deprecated. Use 'var' instead")
public void setName(String name) {
setVar(name);
}
@StrutsTagAttribute(description="The scope in which to assign the variable. Can be <b>application</b>" +
", <b>session</b>, <b>request</b>, <b>page</b>, or <b>action</b>.", defaultValue="action")
public void setScope(String scope) {
this.scope = scope;
}
@StrutsTagAttribute(description="The value that is assigned to the variable named <i>name</i>")
public void setValue(String value) {
this.value = value;
}
@Override
public boolean usesBody() {
return true;
}
}
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