Java example source code file (RawCollectionsExample.java)

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Java - Java tags/keywords

arraylist, collection, event, greetings, gson, jsonarray, jsonparser, override, rawcollectionsexample, string, suppresswarnings, using, util

The RawCollectionsExample.java Java example source code

/*
 * Copyright (C) 2011 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
package com.google.gson.extras.examples.rawcollections;

import java.util.ArrayList;
import java.util.Collection;

import com.google.gson.Gson;
import com.google.gson.JsonArray;
import com.google.gson.JsonParser;

public class RawCollectionsExample {
  static class Event {
    private String name;
    private String source;
    private Event(String name, String source) {
      this.name = name;
      this.source = source;
    }
    @Override
    public String toString() {
      return String.format("(name=%s, source=%s)", name, source);
    }
  }

  @SuppressWarnings({ "unchecked", "rawtypes" })
  public static void main(String[] args) {
    Gson gson = new Gson();
    Collection collection = new ArrayList();
    collection.add("hello");
    collection.add(5);
    collection.add(new Event("GREETINGS", "guest"));
    String json = gson.toJson(collection);
    System.out.println("Using Gson.toJson() on a raw collection: " + json);
    JsonParser parser = new JsonParser();
    JsonArray array = parser.parse(json).getAsJsonArray();
    String message = gson.fromJson(array.get(0), String.class);
    int number = gson.fromJson(array.get(1), int.class);
    Event event = gson.fromJson(array.get(2), Event.class);
    System.out.printf("Using Gson.fromJson() to get: %s, %d, %s", message, number, event);
  }
}