JSON 与JAVA数据的相互转换

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import net.sf.json.JSONArray;
import net.sf.json.JSONException;
import net.sf.json.JSONObject;
import net.sf.json.JSONSerializer;


/**
* json对象转换为java对象
*
* @throws JSONException
*/
@Test
public void jsonToJava(){
String json="[{\"addTime\":\"2011-09-19 14:23:02\",\"iccid\":\"1111\",\"id\":0,\"imei\":\"2222\",\"imsi\":\"3333\",\"phoneType\":\"4444\",\"remark\":\"aaaa\",\"tel\":\"5555\"}]";
//接收{}对象,此处接收数组对象会有异常
if(json.indexOf("[")!=-1){
json=json.replace("[", "");
}
if(json.indexOf("]")!=-1){
json=json.replace("]", "");
}
JSONObject obj=new JSONObject().fromObject(json);
SimInfo simInfo=(SimInfo)JSONObject.toBean(obj, SimInfo.class);
System.out.println("obj: "+simInfo);
System.out.println(simInfo.getAddTime());
System.out.println(simInfo.getIccid());
System.out.println(simInfo.getImei());
System.out.println(simInfo.getImsi());
System.out.println(simInfo.getPhoneType());
System.out.println(simInfo.getRemark());
System.out.println(simInfo.getTel());
System.out.println(simInfo.getId());

DaoFactory.getSimInfoDao().add(simInfo);
}

/**
* 将json转换为java集合对象
*/
@Test
public void jsonToJavas(){
String jsons="[{\"addTime\":\"2011-09-19 14:23:02\",\"iccid\":\"1111\",\"id\":0,\"imei\":\"2222\",\"imsi\":\"3333\",\"phoneType\":\"4444\",\"remark\":\"aaaa\",\"tel\":\"5555\"}," +
"{\"addTime\":\"2011-11-11 14:23:02\",\"iccid\":\"2222\",\"id\":0,\"imei\":\"2222\",\"imsi\":\"3333\",\"phoneType\":\"4444\",\"remark\":\"aaaa\",\"tel\":\"5555\"}]";
List<SimInfo> simInfos = getJavaCollection(new SimInfo(),jsons);
System.out.println(simInfos.size());
for(SimInfo simInfo:simInfos){
System.out.println("addTime: "+simInfo.getAddTime());
System.out.println("=========");
}

}

/**
* 封装将json对象转换为java集合对象
*
* @param <T>
* @param clazz
* @param jsons
* @return
*/
private <T> List<T> getJavaCollection(T clazz, String jsons) {
List<T> objs=null;
JSONArray jsonArray=(JSONArray)JSONSerializer.toJSON(jsons);
if(jsonArray!=null){
objs=new ArrayList<T>();
List list=(List)JSONSerializer.toJava(jsonArray);
for(Object o:list){
JSONObject jsonObject=JSONObject.fromObject(o);
T obj=(T)JSONObject.toBean(jsonObject, clazz.getClass());
objs.add(obj);
}
}
return objs;
}

/**
* java对象转换为json对象
*
* @throws JSONException
*/
@Test
public void javaToJson(){
SimInfo simInfo=new SimInfo();
simInfo.setAddTime(UtilTool.dateToStr(new Date(), null));
simInfo.setIccid("1111");
simInfo.setImei("2222");
simInfo.setImsi("3333");
simInfo.setPhoneType(4);
simInfo.setRemark("aaaa");
simInfo.setTel("5555");
//java对象转换为json对象
String json=new JSONArray().fromObject(simInfo).toString();
//json: [{"addTime":"2011-09-19 14:23:02","iccid":"1111","id":0,"imei":"2222","imsi":"3333","phoneType":"4444","remark":"aaaa","tel":"5555"}]
System.out.println("json: "+json);
}
 


         jackson-core-asl-1.7.2.jar   

         jackson-mapper-asl-1.7.2.jar

            //将一个Java对象转换成JSON
StringWriter writer = new StringWriter();
ObjectMapper mapper = new ObjectMapper();
mapper.writeValue(writer, simInfo);
String json=writer.toString();

           

   基于json-lib.jar包Json实例程序

1.JSONObject to DynaBean
String json = "{name=\"json\",bool:true,int:1,double:2.2}";
JSONObject jsonObject = JSONObject.fromObject(json);
//抽象的写法:DynaBean bean = (DynaBean) JSONSerializer.toJava( jsonObject );
Object bean = JSONObject.toBean(jsonObject);
//Object bean1 = JSONSerializer.toJava(jsonObject);
assertEquals(jsonObject.get("name"), PropertyUtils.getProperty(bean, "name"));
assertEquals(jsonObject.get("bool"), PropertyUtils.getProperty(bean, "bool"));
assertEquals(jsonObject.get("int"), PropertyUtils.getProperty(bean, "int"));
assertEquals(jsonObject.get("double"), PropertyUtils.getProperty(bean, "double"));

2.JSONObject to JavaBean
String json = "{name:\"zhangsan\",age:25,hight:1.72,sex:true}";
JSONObject jsonObject = JSONObject.fromObject(json);
UserBean bean = (UserBean) JSONObject.toBean(jsonObject, UserBean.class);
System.out.println(jsonObject);
理论上,这样就可以了,但时,有异常Caused by: java.lang.NoSuchMethodException: com.json.Json$UserBean.<init>()
             
3.JSONArray to List
String json = "[\"first\",\"second\"]";
JSONArray jsonArray = (JSONArray) JSONSerializer.toJSON(json);
List output = (List) JSONSerializer.toJava(jsonArray);

4.JSONArray to array
String json = "[\"first\",\"second\"]";
JSONArray jsonArray = (JSONArray) JSONSerializer.toJSON(json);
JsonConfig jsonConfig = new JsonConfig();
jsonConfig.setArrayMode(JsonConfig.MODE_OBJECT_ARRAY);
Object[] output = (Object[]) JSONSerializer.toJava(jsonArray, jsonConfig);
Object[] expected = new Object[] { "first", "second" };
ArrayAssertions.assertEquals(expected, output);

5.JSON 字符串 专为 JavaBean(刘慧斌demo 演示需要的jar包在附件里)

String str="[{\"id\":\"328\",\"mestype\":\"inbox\"},{\"id\":\"327\",\"mestype\":\"inbox\"},{\"id\":\"279\",\"mestype\":\"already\"},{\"id\":\"278\",\"mestype\":\"already\"},{\"id\":\"277\",\"mestype\":\"already\"},{\"id\":\"310\",\"mestype\":\"inbox\"},{\"id\":\"308\",\"mestype\":\"inbox\"},{\"id\":\"305\",\"mestype\":\"inbox\"},{\"id\":\"304\",\"mestype\":\"inbox\"},{\"id\":\"303\",\"mestype\":\"inbox\"}]";
JSONArray jsonArray=(JSONArray) JSONSerializer.toJSON(str);
List list=(List)JSONSerializer.toJava(jsonArray);
for (Object obj: list) {
JSONObject jsonObject = JSONObject.fromObject(obj);
MessageBean bean = (MessageBean) JSONObject.toBean(jsonObject, MessageBean.class);
String id=bean.getId()+"";
String type=bean.getMestype();
System.out.println(id+" "+type);
}
System.out.println(list.size());

 















































































































































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