日期:2014-05-16  浏览次数:20430 次

Map,HashMap组装Json数据,jackson简单的入门和解析Json例子
package com.ljl.org.domain;

import java.io.File;
import java.util.HashMap;
import java.util.Map;

import org.codehaus.jackson.JsonFactory;
import org.codehaus.jackson.JsonParser;
import org.codehaus.jackson.JsonToken;
import org.codehaus.jackson.map.ObjectMapper;

import com.google.gson.Gson;
import com.ljl.org.entity.Info;
import com.ljl.org.entity.User;

/**
 *@Author:liangjilong
 *@Date:2013-8-13
 *@Email:jilongliang@sina.com
 *@Version:Version1.0
 *@CopyRight:liangjilong
 *@Description:http://wiki.fasterxml.com/JacksonInFiveMinutes#Full_Data_Binding_.28POJO.29_Example
 *
 *=====================================
	*	=====================================
	*	☆★★建议解析json的有:
	*	1)GSON (gson-2.2.4.jar)
	*	2)json-lib-2.2.3-jdk15.jar--
		
	*	☆不建议使用的:
	*	JackSON比较扯淡(毛线)
		
	*	需要的jar
	*	    http://download.csdn.net/detail/jilongliang/5789041
	*		jackson-all-1.6.2.jar
	*		jackson-core-asl-1.6.2.jar
	*		jackson-mapper-asl-1.6.2.jar
	*		jakarta-oro.jar
	*	=====================================
	*	=====================================
   */
public class Jackson1 {
   private static ObjectMapper mapper = new ObjectMapper();  
   public static void main(String[] args) throws Exception {
	   jackSon1();
	   jackSon2();
  }
   /**
    * 简单的JackSon测试,对比一下,不知道谁抄谁的!Gson和Json-lib-2.2.3-jdk15也有很多相似的
    * 使用者两个技术的人都知道、、、、 
    * ===================================================
    * Gson创建一个JsonParser
	* JsonParser parser = new JsonParser();
	* JsonElement jsonEl = parser.parse(json);
	* ===================================================
	* JackSon 创建一个JsonParser
	*  JsonFactory f = new JsonFactory();//实例JSON工程对象
	*  JsonParser jp = f.createJsonParser(json);
	* ===================================================
    */
   public static void  jackSon1()throws Exception{
	   String json = "[{\"userName\": \"liangjilong\",\"address\":\"广东阳春\"},{\"userName\": \"liangjilong\",\"address\": \"广东阳春\"}]";
	   JsonFactory f = new JsonFactory();//实例JSON工程对象
	   JsonParser jp = f.createJsonParser(json);
	   jp.nextToken();//下一个JsonToken
	   while (jp.nextToken() == JsonToken.START_OBJECT) {
	       User u = mapper.readValue(jp, User.class);//对象化
	       System.out.println(u.getUserName()+"\t"+u.getAddress());
	    }
   }
   /**
    * @throws Exception
    */
   public static void  jackSon2()throws Exception{
	   /**
		  * 组装address对象的数据
		  */
		 Map<String, String> address = new HashMap <String, String>(); 
		 address.put("province", "广东省");
		 address.put("city", "广州市");
		 address.put("district", "天河区");
		 address.put("street", "棠东"); 
		 /**
		  * 组装users对象的数据
		  */
		 Map<String, String> users = new HashMap <String, String>(); 
		 users.put("userName", "liangjilong");
		 users.put("age", "25");
		 users.put("tel", "12396878");
		 users.put("email", "jilongliang@sina.com"); 
		 
		 Map<Object, Object> listsObj = new HashMap <Object, Object>(); 
		 listsObj.put("address",address);//address节点
		 listsObj.put("user",users);//users节点
		 
		 Object obj=listsObj;//转换成对象
		 
		 Map<Object, Object> info = new HashMap <Object, Object>(); 
		 info.put("info", obj);//json的根节点
		 //System.out.println(info);
		 /**
		  * 写
		  */
		 String path="D:/test/json1.txt";
		 mapper.writeValue(new File(path), info);//把数据写入本地文件,JackSon会以json格式写入进去的
		 /**
		  * 读
		  */
		 String jsons=info.toString().replace("=", ":");
		 //用Gson处理/初次使用JackSon找不到处理json数据,由于之前使用Gson就熟悉,就借用一下处理,感觉有点毛线。O(∩_∩)O哈哈~无语.
		 String newJson=new Gson().toJson(info);
		 int start=newJson.indexOf(":")+1;
		 int end=newJson.lastIndexOf("}");
		 jsons="["+newJson.substring(start, end)+"]";//组装JackSon支持的格式.
		 JsonFactory f = new JsonFactory();//实例JSON工程对象
	     JsonParser jp = f.createJsonParser(jsons);
	     jp.nextToken();//下一个JsonToken
	     while (jp.nextToken() == JsonToken.START_OBJECT) {
	       Info in