JSON转换为JAVA对象及日期格式转换处理

1.JSON日期格式转换

默认JSON对DATE类型会转换成一个多属性对象, 而不是单独的一个字符串, 在某些应用处理上不是很方便, 可以利用JsonValueProcessor来实现日期的转换.

默认格式:

"lastUpdate": {
"date": 29,
"day": 3,
"hours": 14,
"minutes": 46,
"month": 1,
"seconds": 41,
"time": 1330498001000,
"timezoneOffset": -480,
"year": 112
},

转换后格式:

"lastUpdate": "2012-02-29 14:46:41"

自定义一个日期处理器:

DateJsonValueProcessor是实现了一个JsonValueProcessor接口(两种方式)

 importjava.text.SimpleDateFormat;
 importjava.util.Date;

 importnet.sf.json.JsonConfig;
 importnet.sf.json.processors.JsonValueProcessor;

 /**
 *JSON日期格式转换
 *
 */
 publicclassDateJsonValueProcessorimplementsJsonValueProcessor
 {
 privateStringformat="yyyy-MM-ddHH:mm:ss";

 publicDateJsonValueProcessor()
 {

 }

 publicDateJsonValueProcessor(Stringformat)
 {

 this.format=format;
 }

 publicObjectprocessArrayValue(Objectvalue,JsonConfigjsonConfig)
 {

 String[]obj={};
 if(valueinstanceofDate[])
 {
 SimpleDateFormatsf=newSimpleDateFormat(format);
 Date[]dates=(Date[])value;
 obj=newString[dates.length];
 for(inti=0;i<dates.length;i++)
 {
 obj[i]=sf.format(dates[i]);
 }
 }
 returnobj;
 }

 publicObjectprocessObjectValue(Stringkey,Objectvalue,JsonConfigjsonConfig)
 {

 if(valueinstanceofDate)
 {
 Stringstr=newSimpleDateFormat(format).format((Date)value);
 returnstr;
 }
 returnvalue;
 }

 publicStringgetFormat()
 {

 returnformat;
 }

 publicvoidsetFormat(Stringformat)
 {

 this.format=format;
 }

 }

或:

 packageorg.ymm.util;

 importjava.text.SimpleDateFormat;
 importnet.sf.json.JsonConfig;
 importnet.sf.json.processors.JsonValueProcessor;

 publicclassDateJsonValueProcessorimplementsJsonValueProcessor
 {

 privateStringformat;
 publicDateJsonValueProcessor(Stringformat){
 this.format=format;
 }

 publicObjectprocessArrayValue(Objectvalue,JsonConfigjsonConfig)
 {
 returnnull;
 }

 publicObjectprocessObjectValue(Stringkey,Objectvalue,JsonConfigjsonConfig)
 {
 if(value==null)
 {
 return"";
 }
 if(valueinstanceofjava.sql.Timestamp)
 {
 Stringstr=newSimpleDateFormat(format).format((java.sql.Timestamp)value);
 returnstr;
 }
 if(valueinstanceofjava.util.Date)
 {
 Stringstr=newSimpleDateFormat(format).format((java.util.Date)value);
 returnstr;
 }

 returnvalue.toString();
 }
 }

转换调用代码:

	public String queryEmpAll() throws IOException{
		System.out.println("queryEmpAll!!!!!!!!!!!!!!!!!!!!!!!");	
//		PrintWriter out=ServletActionContext.getResponse().getWriter();
		
		JsonConfig jsonConfig = new JsonConfig();  
		jsonConfig.registerJsonValueProcessor(java.util.Date.class, new JsonDateValueProcessor()); 
		jsonConfig.registerJsonValueProcessor(java.sql.Timestamp.class, new JsonDateValueProcessor()); 
		
		Map map=new HashMap();
		map.put("total", 3);
		map.put("data", ies.getAll());
		
		JSONObject jn=JSONObject.fromObject(map,jsonConfig);
		
		System.out.println(jn.toString());
//		out.print(jn.toString());
		return null;
	}