1 package org.apache.turbine.modules.screens;
2
3 /*
4 * Licensed to the Apache Software Foundation (ASF) under one
5 * or more contributor license agreements. See the NOTICE file
6 * distributed with this work for additional information
7 * regarding copyright ownership. The ASF licenses this file
8 * to you under the Apache License, Version 2.0 (the
9 * "License"); you may not use this file except in compliance
10 * with the License. You may obtain a copy of the License at
11 *
12 * http://www.apache.org/licenses/LICENSE-2.0
13 *
14 * Unless required by applicable law or agreed to in writing,
15 * software distributed under the License is distributed on an
16 * "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY
17 * KIND, either express or implied. See the License for the
18 * specific language governing permissions and limitations
19 * under the License.
20 */
21
22 import org.apache.commons.lang.StringUtils;
23 import org.apache.commons.lang.exception.ExceptionUtils;
24 import org.apache.turbine.TurbineConstants;
25 import org.apache.turbine.pipeline.PipelineData;
26 import org.apache.turbine.util.RunData;
27 import org.apache.velocity.context.Context;
28
29 /**
30 * VelocityDirectScreen is a screen class which returns its output
31 * directly to the output stream. It can be used if buffering an
32 * output screen isn't possible or the result doesn't fit in the
33 * memory.
34 * <p>
35 * @author <a href="mailto:mbryson@mont.mindspring.com">Dave Bryson</a>
36 * @author <a href="mailto:hps@intermeta.de">Henning P. Schmiedehausen</a>
37 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a>
38 * @version $Id: VelocityDirectScreen.java 1773378 2016-12-09 13:19:59Z tv $
39 */
40 public class VelocityDirectScreen
41 extends VelocityScreen
42 {
43 /** The prefix for lookup up screen pages */
44 private String prefix = getPrefix() + "/";
45
46 /**
47 * This builds the Velocity template.
48 *
49 * @param pipelineData Turbine information.
50 * @return the content of the screen
51 * @throws Exception a generic exception.
52 */
53 @Override
54 public String buildTemplate(PipelineData pipelineData)
55 throws Exception
56 {
57 RunData data = getRunData(pipelineData);
58 Context context = velocity.getContext(pipelineData);
59
60 String screenTemplate = data.getTemplateInfo().getScreenTemplate();
61 String templateName
62 = templateService.getScreenTemplateName(screenTemplate);
63
64 // The Template Service could not find the Screen
65 if (StringUtils.isEmpty(templateName))
66 {
67 log.error("Screen " + screenTemplate + " not found!");
68 throw new Exception("Could not find screen for " + screenTemplate);
69 }
70
71 try
72 {
73 velocity.handleRequest(context,
74 prefix + templateName,
75 data.getResponse().getOutputStream());
76
77 }
78 catch (Exception e)
79 {
80 // If there is an error, build a $processingException and
81 // attempt to call the error.vm template in the screens
82 // directory.
83 context.put (TurbineConstants.PROCESSING_EXCEPTION_PLACEHOLDER, e.toString());
84 context.put (TurbineConstants.STACK_TRACE_PLACEHOLDER, ExceptionUtils.getStackTrace(e));
85
86 velocity.handleRequest(context, prefix + templateError,
87 data.getResponse().getOutputStream());
88 }
89
90 return null;
91 }
92 }