001/* 002 * (C) Copyright 2012-2013 Nuxeo SA (http://nuxeo.com/) and others. 003 * 004 * Licensed under the Apache License, Version 2.0 (the "License"); 005 * you may not use this file except in compliance with the License. 006 * You may obtain a copy of the License at 007 * 008 * http://www.apache.org/licenses/LICENSE-2.0 009 * 010 * Unless required by applicable law or agreed to in writing, software 011 * distributed under the License is distributed on an "AS IS" BASIS, 012 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. 013 * See the License for the specific language governing permissions and 014 * limitations under the License. 015 * 016 */ 017package org.nuxeo.connect.tools.report.client; 018 019import java.util.Stack; 020 021import javax.json.Json; 022import javax.json.JsonArrayBuilder; 023import javax.json.JsonException; 024import javax.json.JsonObjectBuilder; 025import javax.json.stream.JsonParser; 026import javax.json.stream.JsonParser.Event; 027 028/** 029 * 030 * 031 */ 032public class ObjectFeeder { 033 interface Handler { 034 void handle(JsonArrayBuilder builder); 035 036 void handle(JsonObjectBuilder builder); 037 038 void handle(Event current, JsonParser parser); 039 } 040 041 class ArrayHandler implements Handler { 042 final JsonArrayBuilder builder; 043 044 ArrayHandler(JsonArrayBuilder aBuilder) { 045 builder = aBuilder; 046 } 047 048 @Override 049 public void handle(Event event, JsonParser parser) { 050 switch (event) { 051 case START_ARRAY: 052 stack.push(new ArrayHandler(Json.createArrayBuilder())); 053 break; 054 case START_OBJECT: 055 stack.push(new ObjectHandler(Json.createObjectBuilder())); 056 break; 057 case END_ARRAY: 058 stack.pop(); 059 stack.peek().handle(builder); 060 break; 061 case END_OBJECT: 062 stack.pop(); 063 stack.peek().handle(builder); 064 break; 065 case VALUE_FALSE: 066 builder.add(false); 067 break; 068 case VALUE_TRUE: 069 builder.add(true); 070 break; 071 case VALUE_STRING: 072 builder.add(parser.getString()); 073 break; 074 case VALUE_NULL: 075 builder.addNull(); 076 break; 077 case VALUE_NUMBER: 078 if (parser.isIntegralNumber()) { 079 builder.add(parser.getLong()); 080 } else { 081 builder.add(parser.getBigDecimal()); 082 } 083 break; 084 default: 085 throw new IllegalStateException("Cannot handle " + event + " while parsing object"); 086 } 087 } 088 089 @Override 090 public void handle(JsonArrayBuilder builder) { 091 this.builder.add(builder); 092 } 093 094 @Override 095 public void handle(JsonObjectBuilder builder) { 096 this.builder.add(builder); 097 } 098 } 099 100 class ObjectHandler implements Handler { 101 final JsonObjectBuilder builder; 102 103 ObjectHandler(JsonObjectBuilder aBuilder) { 104 builder = aBuilder; 105 } 106 107 String name; 108 109 @Override 110 public void handle(Event anEvent, JsonParser aParser) { 111 switch (anEvent) { 112 case END_OBJECT: 113 stack.pop(); 114 if (!stack.isEmpty()) { 115 stack.peek().handle(builder); 116 } 117 break; 118 case KEY_NAME: 119 name = aParser.getString(); 120 switch (aParser.next()) { 121 case START_ARRAY: 122 stack.push(new ArrayHandler(Json.createArrayBuilder())); 123 break; 124 case START_OBJECT: 125 stack.push(new ObjectHandler(Json.createObjectBuilder())); 126 break; 127 case VALUE_FALSE: 128 builder.add(name, false); 129 break; 130 case VALUE_TRUE: 131 builder.add(name, true); 132 break; 133 case VALUE_NULL: 134 builder.addNull(name); 135 break; 136 case VALUE_STRING: 137 builder.add(name, aParser.getString()); 138 break; 139 case VALUE_NUMBER: 140 if (aParser.isIntegralNumber()) { 141 builder.add(name, aParser.getLong()); 142 } else { 143 builder.add(name, aParser.getBigDecimal()); 144 } 145 break; 146 default: 147 throw new IllegalStateException("Cannot handle " + anEvent + " while parsing object"); 148 } 149 break; 150 default: 151 throw new IllegalStateException("Cannot handle " + anEvent + " while parsing object"); 152 } 153 } 154 155 @Override 156 public void handle(JsonArrayBuilder builder) { 157 this.builder.add(name, builder); 158 } 159 160 @Override 161 public void handle(JsonObjectBuilder builder) { 162 this.builder.add(name, builder); 163 } 164 165 } 166 167 final Stack<Handler> stack = new Stack<>(); 168 169 public JsonArrayBuilder buildArray(JsonArrayBuilder builder, JsonParser parser) { 170 if (!parser.hasNext()) { 171 throw new JsonException("not an array"); 172 } 173 if (parser.next() != Event.START_ARRAY) { 174 throw new IllegalStateException("Not an array"); 175 } 176 stack.push(new ArrayHandler(builder)); 177 try { 178 dofeed(parser); 179 } finally { 180 stack.clear(); 181 } 182 return builder; 183 } 184 185 public JsonObjectBuilder feed(JsonObjectBuilder builder, JsonParser parser) { 186 if (!parser.hasNext()) { 187 throw new JsonException("not an array"); 188 } 189 if (parser.next() != Event.START_OBJECT) { 190 throw new IllegalStateException("Not an array"); 191 } 192 stack.push(new ObjectHandler(builder)); 193 try { 194 dofeed(parser); 195 } finally { 196 stack.clear(); 197 } 198 return builder; 199 } 200 201 void dofeed(JsonParser parser) { 202 while (parser.hasNext()) { 203 stack.peek().handle(parser.next(), parser); 204 } 205 } 206}