SerializingView.java

   1 /*
   2  * Copyright (C) 2010 Mathieu Baudier <mbaudier@argeo.org>
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at
   7  *
   8  *         http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 package org.argeo.server.mvc;
  18
  19 import java.util.Locale;
  20 import java.util.Map;
  21
  22 import javax.servlet.http.HttpServletRequest;
  23 import javax.servlet.http.HttpServletResponse;
  24
  25 import org.argeo.ArgeoException;
  26 import org.argeo.server.ServerAnswer;
  27 import org.argeo.server.ServerSerializer;
  28 import org.springframework.validation.BindingResult;
  29 import org.springframework.web.servlet.View;
  30 import org.springframework.web.servlet.view.AbstractView;
  31
  32 /**
  33  * Can be used as a standalone {@link View} or using
  34  * {@link SerializingViewResolver}
  35  */
  36 public class SerializingView extends AbstractView implements MvcConstants {
  37         private final String viewName;
  38         private final Locale locale;
  39
  40         private ServerSerializer serializer;
  41
  42         public SerializingView() {
  43                 this.viewName = null;
  44                 this.locale = Locale.getDefault();
  45         }
  46
  47         public SerializingView(String viewName, Locale locale,
  48                         ServerSerializer serializer) {
  49                 this.viewName = viewName;
  50                 this.locale = locale;
  51                 this.serializer = serializer;
  52         }
  53
  54         @SuppressWarnings( { "unchecked", "restriction" })
  55         @Override
  56         protected void renderMergedOutputModel(Map model,
  57                         HttpServletRequest request, HttpServletResponse response)
  58                         throws Exception {
  59                 Boolean serverAnswersAsHtml = model
  60                                 .containsKey(ANSWER_MODEL_KEY_AS_HTML);
  61
  62                 final Object answer = findAnswerInModel(model);
  63
  64                 if ((answer instanceof ServerAnswer) && serverAnswersAsHtml) {
  65                         response.setContentType("text/html");
  66                         ServerAnswer serverAnswer = (ServerAnswer) answer;
  67                         response.getWriter().append("<pre>");
  68                         response.getWriter().append(serverAnswer.getMessage());
  69                         response.getWriter().append("</pre>");
  70                 } else {
  71                         serializer.serialize(answer, request, response);
  72                 }
  73         }
  74
  75         @SuppressWarnings("unchecked")
  76         protected Object findAnswerInModel(Map model) {
  77                 if (model.size() == 1) {
  78                         return model.values().iterator().next();
  79                 } else if (model.size() == 2) {
  80                         boolean otherIsBindingResult = false;
  81                         Object answerValue = null;
  82                         for (Object value : model.values()) {
  83                                 if (value instanceof BindingResult)
  84                                         otherIsBindingResult = true;
  85                                 else
  86                                         answerValue = value;
  87                         }
  88
  89                         if (otherIsBindingResult)
  90                                 return answerValue;
  91                 }
  92
  93                 if (model.containsKey(ANSWER_MODEL_KEY)) {
  94                         return model.get(ANSWER_MODEL_KEY);
  95                 } else if (model.containsKey(ANSWER_MODEL_KEY_AS_HTML)) {
  96                         return model.get(ANSWER_MODEL_KEY_AS_HTML);
  97                 } else if (viewName != null && model.containsKey(viewName)) {
  98                         return model.get(viewName);
  99                 } else {
 100                         if (model.size() == 0)
 101                                 throw new ArgeoException("Model is empty.");
 102                         else
 103                                 throw new ArgeoException(
 104                                                 "Model has a size different from 1. Specify a modelKey.");
 105                 }
 106         }
 107
 108         public String getViewName() {
 109                 return viewName;
 110         }
 111
 112         public Locale getLocale() {
 113                 return locale;
 114         }
 115
 116         public void setSerializer(ServerSerializer serializer) {
 117                 this.serializer = serializer;
 118         }
 119
 120 }