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 23 // Turbine stuff. 24 25 import org.apache.ecs.ConcreteElement; 26 import org.apache.turbine.modules.Screen; 27 import org.apache.turbine.pipeline.PipelineData; 28 import org.apache.turbine.util.RunData; 29 30 /** 31 * Base class for writing Screens that output binary data. This class 32 * is provided as a helper class for those who want to write Screens 33 * that output raw binary data. For example, it may be extended into 34 * a Screen that outputs a SVG file or a SWF (Flash Player format) 35 * movie. The only thing one has to do is to implement the two 36 * methods <code>getContentType(RunData data)</code> and 37 * <code>doOutput(RunData data)</code> (see below). 38 * 39 * <p> You migth want to take a look at the ImageServer screen class 40 * contained in the TDK.<br> 41 * 42 * @author <a href="mailto:rkoenig@chez.com">Regis Koenig</a> 43 * @author <a href="mailto:peter@courcoux.biz">Peter Courcoux</a> 44 * @version $Id: RawScreen.java 938645 2010-04-27 20:57:51Z tv $ 45 */ 46 public abstract class RawScreen extends Screen 47 { 48 /** 49 * Build the Screen. This method actually makes a call to the 50 * doOutput() method in order to generate the Screen content. 51 * 52 * @deprecated Use PipelineData version instead. 53 * @param data Turbine information. 54 * @return A ConcreteElement. 55 * @exception Exception, a generic exception. 56 */ 57 protected final ConcreteElement doBuild(RunData data) 58 throws Exception 59 { 60 data.getResponse().setContentType(getContentType(data)); 61 data.declareDirectResponse(); 62 doOutput(data); 63 return null; 64 } 65 66 /** 67 * Build the Screen. This method actually makes a call to the 68 * doOutput() method in order to generate the Screen content. 69 * 70 * @param data Turbine information. 71 * @return A ConcreteElement. 72 * @exception Exception, a generic exception. 73 */ 74 protected final ConcreteElement doBuild(PipelineData pipelineData) 75 throws Exception 76 { 77 RunData data = getRunData(pipelineData); 78 return doBuild(data); 79 } 80 81 82 /** 83 * Set the content type. This method should be overidden to 84 * actually set the real content-type header of the output. 85 * 86 * @deprecated Use PipelineData version instead. 87 * @param data Turbine information. 88 * @return A String with the content type. 89 */ 90 protected abstract String getContentType(RunData data); 91 92 /** 93 * Set the content type. This method should be overidden to 94 * actually set the real content-type header of the output. 95 * 96 * @param data Turbine information. 97 * @return A String with the content type. 98 */ 99 protected String getContentType(PipelineData pipelineData) 100 { 101 RunData data = getRunData(pipelineData); 102 return getContentType(data); 103 } 104 105 106 /** 107 * Actually output the dynamic content. The OutputStream can be 108 * accessed like this: <pre>OutputStream out = 109 * data.getResponse().getOutputStream();</pre>. 110 * 111 * @deprecated Use PipelineData version instead. 112 * @param data Turbine information. 113 * @exception Exception, a generic exception. 114 */ 115 protected abstract void doOutput(RunData data) 116 throws Exception; 117 118 /** 119 * Actually output the dynamic content. The OutputStream can be 120 * accessed like this: <pre>OutputStream out = 121 * data.getResponse().getOutputStream();</pre>. 122 * 123 * @param data Turbine information. 124 * @exception Exception, a generic exception. 125 */ 126 protected void doOutput(PipelineData pipelineData) 127 throws Exception 128 { 129 RunData data = getRunData(pipelineData); 130 doOutput(data); 131 } 132 133 134 /** 135 * The layout must be set to null. 136 * 137 * @deprecated Use PipelineData version instead. 138 * @param data Turbine information. 139 * @return A null String. 140 */ 141 public final String getLayout(RunData data) 142 { 143 return null; 144 } 145 146 /** 147 * The layout must be set to null. 148 * 149 * @param data Turbine information. 150 * @return A null String. 151 */ 152 public final String getLayout(PipelineData pipelineData) 153 { 154 return null; 155 } 156 157 158 159 }