org.apache.struts2.components.GenericUIBean Maven / Gradle / Ivy
/*
* 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 javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import org.apache.struts2.views.annotations.StrutsTag;
import org.apache.struts2.util.ContainUtil;
import com.opensymphony.xwork2.util.ValueStack;
/**
*
*
* Renders an custom UI widget using the specified templates. Additional objects can be passed in to the template
* using the param tags.
*
*
* Freemarker:
* Objects provided can be retrieve from within the template via $parameters._paramname_.
*
* JSP:
* Objects provided can be retrieve from within the template via <s:property value="%{parameters._paramname_}" />
*
*
* In the bottom JSP and Velocity samples, two parameters are being passed in to the component. From within the
* component, they can be accessed as:
*
*
* Freemarker:
* $parameters.get('key1') and $parameters.get('key2') or $parameters.key1 and $parameters.key2
*
* JSP:
*
* <s:property value="%{parameters.key1}" /> and <s:property value="%{'parameters.key2'}" /> or
* <s:property value="%{parameters.get('key1')}" /> and <s:property value="%{parameters.get('key2')}" />
*
*
*
* Currently, your custom UI components can be written in Velocity, JSP, or Freemarker, and the correct rendering
* engine will be found based on file extension.
*
*
*
* Remember: the value params will always be resolved against the ValueStack so if you mean to pass a
* string literal to your component, make sure to wrap it in single quotes i.e. value="'value1'" (note the opening "' and closing '" otherwise, the the value
* stack will search for an Object on the stack with a method of getValue1().
*
*
*
* Examples
*
*
*
* JSP
*
*
* <s:component template="/my/custom/component.vm"/>
*
* or
*
* <s:component template="/my/custom/component.vm">
* <s:param name="key1" value="value1"/>
* <s:param name="key2" value="value2"/>
* </s:component>
*
*
*
* Velocity
*
*
* #s-component( "template=/my/custom/component.vm" )
*
* or
*
* #s-component( "template=/my/custom/component.vm" )
* #s-param( "name=key1" "value=value1" )
* #s-param( "name=key2" "value=value2" )
* #end
*
*
*
* Freemarker
*
*
* <@s..component template="/my/custom/component.ftl" />
*
* or
*
* <@s..component template="/my/custom/component.ftl">
* <@s..param name="key1" value="%{'value1'}" />
* <@s..param name="key2" value="%{'value2'}" />
* </@s..component>
*
*
*
*
* NOTE:
*
*
* If Jsp is used as the template, the jsp template itself must lie within the
* webapp itself and not the classpath. Unlike Freemarker or Velocity, JSP template
* could not be picked up from the classpath.
*
*
*
*/
@StrutsTag(name="component", tldTagClass="org.apache.struts2.views.jsp.ui.ComponentTag", description="Render a custom ui widget")
public class GenericUIBean extends UIBean {
private final static String TEMPLATE = "empty";
public GenericUIBean(ValueStack stack, HttpServletRequest request, HttpServletResponse response) {
super(stack, request, response);
}
public boolean contains(Object obj1, Object obj2) {
return ContainUtil.contains(obj1, obj2);
}
protected String getDefaultTemplate() {
return TEMPLATE;
}
}