001: /*
002: * $Id: GenericUIBean.java 497654 2007-01-19 00:21:57Z rgielen $
003: *
004: * Licensed to the Apache Software Foundation (ASF) under one
005: * or more contributor license agreements. See the NOTICE file
006: * distributed with this work for additional information
007: * regarding copyright ownership. The ASF licenses this file
008: * to you under the Apache License, Version 2.0 (the
009: * "License"); you may not use this file except in compliance
010: * with the License. You may obtain a copy of the License at
011: *
012: * http://www.apache.org/licenses/LICENSE-2.0
013: *
014: * Unless required by applicable law or agreed to in writing,
015: * software distributed under the License is distributed on an
016: * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
017: * KIND, either express or implied. See the License for the
018: * specific language governing permissions and limitations
019: * under the License.
020: */
021: package org.apache.struts2.components;
022:
023: import javax.servlet.http.HttpServletRequest;
024: import javax.servlet.http.HttpServletResponse;
025:
026: import org.apache.struts2.views.annotations.StrutsTag;
027: import org.apache.struts2.util.ContainUtil;
028:
029: import com.opensymphony.xwork2.util.ValueStack;
030:
031: /**
032: * <!-- START SNIPPET: javadoc -->
033: *
034: * Renders an custom UI widget using the specified templates. Additional objects can be passed in to the template
035: * using the param tags.<p/>
036: *
037: * <b>Freemarker:</b><p/>
038: * Objects provided can be retrieve from within the template via $parameters._paramname_.<p/>
039: *
040: * <b>Jsp:</b><p/>
041: * Objects provided can be retrieve from within the template via <s:property value="%{parameters._paramname_}" /><p/>
042: *
043: *
044: * In the bottom JSP and Velocity samples, two parameters are being passed in to the component. From within the
045: * component, they can be accessed as:- <p/>
046: *
047: * <b>Freemarker:</b><p/>
048: * $parameters.get('key1') and $parameters.get('key2') or $parameters.key1 and $parameters.key2<p/>
049: *
050: * <b>Jsp:</b><p/>
051: * <s:property value="%{parameters.key1}" /> and <s:property value="%{'parameters.key2'}" /> or
052: * <s:property value="%{parameters.get('key1')}" /> and <s:property value="%{parameters.get('key2')}" /><p/>
053: *
054: * Currently, your custom UI components can be written in Velocity, JSP, or Freemarker, and the correct rendering
055: * engine will be found based on file extension.<p/>
056: *
057: * <b>Remember:</b> the value params will always be resolved against the ValueStack so if you mean to pass a
058: * string literal to your component, make sure to wrap it in quotes i.e. value="'value1'" otherwise, the the value
059: * stack will search for an Object on the stack with a method of getValue1(). (now that i've written this, i'm not
060: * entirely sure this is the case. i should verify this manana)<p/>
061: *
062: * <!-- END SNIPPET: javadoc -->
063: *
064: * <p/> <b>Examples</b>
065: *
066: * <pre>
067: * <!-- START SNIPPET: example -->
068: * JSP
069: * <s:component template="/my/custom/component.vm"/>
070: *
071: * or
072: *
073: * <s:component template="/my/custom/component.vm">
074: * <s:param name="key1" value="value1"/>
075: * <s:param name="key2" value="value2"/>
076: * </s:component>
077: *
078: * Velocity
079: * #s-component( "template=/my/custom/component.vm" )
080: *
081: * or
082: *
083: * #s-component( "template=/my/custom/component.vm" )
084: * #s-param( "name=key1" "value=value1" )
085: * #s-param( "name=key2" "value=value2" )
086: * #end
087: *
088: * Freemarker
089: * <@s..component template="/my/custom/component.ftl" />
090: *
091: * or
092: *
093: * <@s..component template="/my/custom/component.ftl">
094: * <@s..param name="key1" value="%{'value1'}" />
095: * <@s..param name="key2" value="%{'value2'}" />
096: * </@s..component>
097: *
098: * <!-- END SNIPPET: example -->
099: * </pre>
100: *
101: * <p/>
102: *
103: * <b>NOTE:</b>
104: * <!-- START SNIPPET: note -->
105: *
106: * If Jsp is used as the template, the jsp template itself must lie within the
107: * webapp itself and not the classpath. Unlike Freemarker or Velocity, JSP template
108: * could not be picked up from the classpath.
109: *
110: * <!-- END SNIPPET: note -->
111: *
112: */
113: @StrutsTag(name="component",tldTagClass="org.apache.struts2.views.jsp.ui.ComponentTag",description="Render a custom ui widget")
114: public class GenericUIBean extends UIBean {
115: private final static String TEMPLATE = "empty";
116:
117: public GenericUIBean(ValueStack stack, HttpServletRequest request,
118: HttpServletResponse response) {
119: super (stack, request, response);
120: }
121:
122: public boolean contains(Object obj1, Object obj2) {
123: return ContainUtil.contains(obj1, obj2);
124: }
125:
126: protected String getDefaultTemplate() {
127: return TEMPLATE;
128: }
129: }
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