cdmlib-remote/src/main/java/eu/etaxonomy/cdm/remote/view/JsonView.java

   1 // $Id$
   2 /**
   3 * Copyright (C) 2007 EDIT
   4 * European Distributed Institute of Taxonomy
   5 * http://www.e-taxonomy.eu
   6 *
   7 * The contents of this file are subject to the Mozilla Public License Version 1.1
   8 * See LICENSE.TXT at the top of this package for the full license terms.
   9 */
  10 package eu.etaxonomy.cdm.remote.view;
  11
  12 import java.io.PrintWriter;
  13 import java.util.Collection;
  14 import java.util.Map;
  15
  16 import javax.servlet.http.HttpServletRequest;
  17 import javax.servlet.http.HttpServletResponse;
  18
  19 import net.sf.json.JSON;
  20 import net.sf.json.JSONArray;
  21 import net.sf.json.JSONObject;
  22 import net.sf.json.JsonConfig;
  23 import net.sf.json.xml.XMLSerializer;
  24
  25 import org.apache.log4j.Logger;
  26 import org.springframework.web.servlet.View;
  27
  28
  29 public class JsonView extends BaseView implements View{
  30
  31         public static final Logger logger = Logger.getLogger(JsonView.class);
  32
  33         private JsonConfig jsonConfig;
  34
  35         public enum Type{
  36                 JSON("application/json"),
  37                 XML("application/xml");
  38
  39                 private String contentType;
  40
  41                 Type(String contentType){
  42                         this.contentType = contentType;
  43                 }
  44
  45                 public String getContentType(){
  46                         return contentType;
  47                 }
  48         }
  49
  50         private Type type = Type.JSON;
  51
  52         private String xsl;
  53
  54         public void setXsl(String xsl) {
  55                 this.xsl = xsl;
  56         }
  57
  58         public Type getType() {
  59                 return type;
  60         }
  61
  62         /**
  63          * Default is Type.JSON
  64          * @param type
  65          */
  66         public void setType(Type type) {
  67                 this.type = type;
  68         }
  69
  70         public void setJsonConfig(JsonConfig jsonConfig) {
  71                 this.jsonConfig = jsonConfig;
  72         }
  73
  74         /*
  75          * (non-Javadoc)
  76          * @see org.springframework.web.servlet.View#getContentType()
  77          */
  78         public String getContentType() {
  79                 return type.getContentType();
  80         }
  81
  82         public void render(Object entity, PrintWriter writer) throws Exception {
  83
  84
  85                 // create JSON Object
  86                 boolean isCollectionType = false;
  87                 JSON jsonObj;
  88                 if (entity == null){
  89                   jsonObj = JSONObject.fromObject("{}");
  90                 } else if(Collection.class.isAssignableFrom(entity.getClass())){
  91                         isCollectionType = true;
  92                         jsonObj = JSONArray.fromObject(entity, jsonConfig);
  93                 }else if(entity instanceof String){
  94                         jsonObj = JSONObject.fromObject("{\"String\":\""+entity.toString().replace("\"", "\\\"")+"\"}");
  95                 } else if(entity instanceof Integer){
  96                         jsonObj = JSONObject.fromObject("{\"Integer\":"+((Integer)entity).intValue()+"}");
  97                 } else if(entity instanceof Boolean){
  98                         jsonObj = JSONObject.fromObject("{\"Boolean\":"+((Boolean)entity).toString()+"}");
  99                 } else {
 100                         jsonObj = JSONObject.fromObject(entity, jsonConfig);
 101                 }
 102
 103                 if(type.equals(Type.XML)){
 104                         XMLSerializer xmlSerializer = new XMLSerializer();
 105                         if(isCollectionType){
 106                                 xmlSerializer.setArrayName(entity.getClass().getSimpleName());
 107                                 Class elementType = Object.class;
 108                                 Collection c = (Collection)entity;
 109                                 if(c.size() > 0){
 110                                         elementType = c.iterator().next().getClass();
 111                                 }
 112                                 xmlSerializer.setObjectName(elementType.getSimpleName());
 113                         } else if(entity != null){
 114                                 xmlSerializer.setObjectName(entity.getClass().getSimpleName());
 115                         }
 116                         String xml = xmlSerializer.write( jsonObj );
 117                         if(xsl != null){
 118                                 String xslInclude = "\r\n<?xml-stylesheet type=\"text/xsl\" href=\"human.xsl\"?>\r\n";
 119                                 xml = xml.replaceFirst("\r\n", xslInclude);
 120                         }
 121                         writer.append(xml);
 122                 } else {
 123                         // assuming json
 124                         writer.append(jsonObj.toString());
 125                 }
 126                 //TODO resp.setContentType(type);
 127                 writer.flush();
 128         }
 129
 130         /*
 131          * (non-Javadoc)
 132          * @see org.springframework.web.servlet.View#render(java.util.Map, javax.servlet.http.HttpServletRequest, javax.servlet.http.HttpServletResponse)
 133          */
 134         public void render(Map model, HttpServletRequest request, HttpServletResponse response) throws Exception {
 135
 136                 // Retrieve data from model
 137                 Object entity = getResponseData(model);
 138
 139                 // set content type
 140                 response.setContentType(type.getContentType());
 141
 142                 // render
 143                 render(entity, response.getWriter());
 144
 145         }
 146 }