1   /**
2    * Copyright (c) 2000-2007 Liferay, Inc. All rights reserved.
3    *
4    * Permission is hereby granted, free of charge, to any person obtaining a copy
5    * of this software and associated documentation files (the "Software"), to deal
6    * in the Software without restriction, including without limitation the rights
7    * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8    * copies of the Software, and to permit persons to whom the Software is
9    * furnished to do so, subject to the following conditions:
10   *
11   * The above copyright notice and this permission notice shall be included in
12   * all copies or substantial portions of the Software.
13   *
14   * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15   * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16   * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17   * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18   * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19   * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20   * SOFTWARE.
21   */
22  
23  package com.liferay.portlet;
24  
25  import com.liferay.portal.kernel.util.StringPool;
26  import com.liferay.portal.struts.StrutsUtil;
27  import com.liferay.portal.velocity.VelocityResourceListener;
28  
29  import java.io.IOException;
30  import java.io.PrintWriter;
31  
32  import javax.portlet.ActionRequest;
33  import javax.portlet.ActionResponse;
34  import javax.portlet.GenericPortlet;
35  import javax.portlet.PortletConfig;
36  import javax.portlet.PortletContext;
37  import javax.portlet.PortletException;
38  import javax.portlet.PortletRequest;
39  import javax.portlet.PortletResponse;
40  import javax.portlet.RenderRequest;
41  import javax.portlet.RenderResponse;
42  
43  import org.apache.velocity.Template;
44  import org.apache.velocity.VelocityContext;
45  import org.apache.velocity.context.Context;
46  import org.apache.velocity.io.VelocityWriter;
47  import org.apache.velocity.runtime.RuntimeSingleton;
48  import org.apache.velocity.util.SimplePool;
49  
50  /**
51   * <a href="VelocityPortlet.java.html"><b><i>View Source</i></b></a>
52   *
53   * @author Brian Wing Shun Chan
54   * @author Steven P. Goldsmith
55   *
56   */
57  public class VelocityPortlet extends GenericPortlet {
58  
59      /**
60       * The context key for the portlet request.
61       */
62      public static final String REQUEST = "VelocityPortlet.portletRequest";
63  
64      /**
65       * The context key for the portlet response.
66       */
67      public static final String RESPONSE = "VelocityPortlet.portletResponse";
68  
69      /**
70       * Cache of writers.
71       */
72      private static SimplePool writerPool = new SimplePool(40);
73  
74      public void init(PortletConfig config) throws PortletException {
75          super.init(config);
76  
77          PortletContext portletCtx = config.getPortletContext();
78  
79          _portletContextName = portletCtx.getPortletContextName();
80  
81          _editTemplate = getInitParameter("edit-template");
82          _helpTemplate = getInitParameter("help-template");
83          _viewTemplate = getInitParameter("view-template");
84      }
85  
86      public void processAction(ActionRequest req, ActionResponse res)
87          throws IOException, PortletException {
88      }
89  
90      public void doEdit(RenderRequest req, RenderResponse res)
91          throws IOException, PortletException {
92  
93          if (req.getPreferences() == null) {
94              super.doEdit(req, res);
95          }
96          else {
97              try {
98                  mergeTemplate(getTemplate(_editTemplate), req, res);
99              }
100             catch (Exception e) {
101                 throw new PortletException(e);
102             }
103         }
104     }
105 
106     public void doHelp(RenderRequest req, RenderResponse res)
107         throws IOException, PortletException {
108 
109         try {
110             mergeTemplate(getTemplate(_helpTemplate), req, res);
111         }
112         catch (Exception e) {
113             throw new PortletException(e);
114         }
115     }
116 
117     public void doView(RenderRequest req, RenderResponse res)
118         throws IOException, PortletException {
119 
120         try {
121             mergeTemplate(getTemplate(_viewTemplate), req, res);
122         }
123         catch (Exception e) {
124             throw new PortletException(e);
125         }
126     }
127 
128     protected Context getContext(PortletRequest req, PortletResponse res) {
129         Context context = new VelocityContext();
130 
131         context.put(REQUEST, req);
132         context.put(RESPONSE, res);
133 
134         return context;
135     }
136 
137     protected Template getTemplate(String name) throws Exception {
138         return RuntimeSingleton.getTemplate(
139             _portletContextName + VelocityResourceListener.SERVLET_SEPARATOR +
140                 StrutsUtil.TEXT_HTML_DIR + name, StringPool.UTF8);
141     }
142 
143     protected Template getTemplate(String name, String encoding)
144         throws Exception {
145 
146         return RuntimeSingleton.getTemplate(
147             StrutsUtil.TEXT_HTML_DIR + name, encoding);
148     }
149 
150     protected void mergeTemplate(
151             Template template, RenderRequest req, RenderResponse res)
152         throws Exception {
153 
154         mergeTemplate(template, getContext(req, res), req, res);
155     }
156 
157     protected void mergeTemplate(
158             Template template, Context context, RenderRequest req,
159             RenderResponse res)
160         throws Exception {
161 
162         res.setContentType(req.getResponseContentType());
163 
164         VelocityWriter velocityWriter = null;
165 
166         try {
167             velocityWriter = (VelocityWriter)writerPool.get();
168 
169             PrintWriter output = res.getWriter();
170 
171             if (velocityWriter == null) {
172                 velocityWriter = new VelocityWriter(output, 4 * 1024, true);
173             }
174             else {
175                 velocityWriter.recycle(output);
176             }
177 
178             template.merge(context, velocityWriter);
179         }
180         finally {
181             try {
182                 if (velocityWriter != null) {
183                     velocityWriter.flush();
184                     velocityWriter.recycle(null);
185 
186                     writerPool.put(velocityWriter);
187                 }
188             }
189             catch (Exception e) {
190             }
191         }
192     }
193 
194     private String _portletContextName;
195     private String _editTemplate;
196     private String _helpTemplate;
197     private String _viewTemplate;
198 
199 }