AbJsonUtil.java

/*
 * Copyright (C) 2012 www.amsoft.cn
 * 
 * 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.ab.util;

import java.lang.reflect.Type;
import java.util.ArrayList;
import java.util.List;

import com.google.gson.Gson;
import com.google.gson.GsonBuilder;
import com.google.gson.reflect.TypeToken;

// TODO: Auto-generated Javadoc

/**
 * © 2012 amsoft.cn 
 * 名称：AbStrUtil.java 
 * 描述：json处理类.
 *
 * @author 还如一梦中
 * @version v1.0
 * @date：2013-01-17 下午11:52:13
 * @param <T>
 */
public class AbJsonUtil {
	
	private static GsonBuilder gsonBuilder = new GsonBuilder();
	
	/**
	 * 
	 * 描述：将对象转化为json.
	 * @param list
	 * @return
	 */
	public static String toJson(Object src) {
		String json = null;
		try {
			Gson gson = gsonBuilder.create();
			json = gson.toJson(src);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return json;
	}

	/**
	 * 
	 * 描述：将列表转化为json.
	 * @param list
	 * @return
	 */
	public static String toJson(List<?> list) {
		String json = null;
		try {
			Gson gson = gsonBuilder.create();
			json = gson.toJson(list);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return json;
	}
	
	/**
	 * 
	 * 描述：将json转化为列表.
	 * @param json
	 * @param typeToken new TypeToken<ArrayList<?>>() {};
	 * @return
	 */
	public static <T> T fromJson(String json,TypeToken<T> typeToken) {
		List<?> list = null;
		try {
			Gson gson = gsonBuilder.create();
			Type type = typeToken.getType();
			list = gson.fromJson(json,type);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return (T)list;
	}
	
	/**
	 * 
	 * 描述：将json转化为对象.
	 * @param json
	 * @param clazz
	 * @return
	 */
	public static <T> T fromJson(String json,Class<T> clazz) {
		Object obj = null;
		try {
			Gson gson = gsonBuilder.create();
			obj = gson.fromJson(json,clazz);
		} catch (Exception e) {
			e.printStackTrace();
		}
		return (T)obj;
	}
	
	/**
     * The main method.
     *
     * @param args the arguments
     */
    public static void main(String[] args) {
    	List<User> list = (List<User>)fromJson("[{id:1,name:22},{id:2,name:33}]",new TypeToken<ArrayList<User>>(){});
		System.out.println(list.size());
		for(User u:list){
			System.out.println(u.getName());
		}
		
		User u = (User)fromJson("{id:1,name:22}",User.class);
		System.out.println(u.getName());
	}
    
    static class User{
    	String id;
        String name;
		public String getId() {
			return id;
		}
		public void setId(String id) {
			this.id = id;
		}
		public String getName() {
			return name;
		}
		public void setName(String name) {
			this.name = name;
		}
        
    }

	public static void setGsonBuilderDateFormat(String format) {
		  gsonBuilder.setDateFormat(format);
	}
    

}