使用Gson解析json数据

1.当json数据是JsonObject时对应大括号2.当json数据是jsonArray时对应中括号[Person [name=xiaoming, age=1, address=meiguo, colorString= null, height =0], Person [name=xiaoming1, age=2, address=meiguo1, colorString= null, height =0], Person [name=xiaoming2, age=3, address=meiguo2, colorString= null, height =0]][{"name":"xiaoming","age":1,"address":"meiguo","colorString":null,"height":0},{"name":"xiaoming1","age":2,"address":"meiguo1","colorString":null,"height":0},{"name":"xiaoming2","age":3,"address":"meiguo2","colorString":null,"height":0}]

/** * @param args * 实体类中增加属性,而json数据中没有该字段,不影响生成实体类,则生成的实体json数据不包含该字段部分为默认值 * 使用Gson gson = new GsonBuilder().serializeNulls().create();在json数据的字段值值为空的时候也保留该字符串 */public static void main(String[] args) {        // TODO Auto-generated method stub            String jsonString ="{\"name\":\"xiaoming\",\"age\" : 1,\"address\":\"meiguo\"}";                String arrayString ="{\"list\":[{\"name\":\"xiaoming\",\"age\" : 1,\"address\":\"meiguo\"}," +                "{\"name\":\"xiaoming1\",\"age\" : 2,\"address\":\"meiguo1\"}," +                "{\"name\":\"xiaoming2\",\"age\" : 3,\"address\":\"meiguo2\"}]}";        String arrayStrings ="[{\"name\":\"xiaoming\",\"age\" : 1,\"address\":\"meiguo\"}," +                "{\"name\":\"xiaoming1\",\"age\" : 2,\"address\":\"meiguo1\"}," +                "{\"name\":\"xiaoming2\",\"age\" : 3,\"address\":\"meiguo2\"}]";testJsonToObject(jsonString);testObjectToJson(arrayString);    tokenObjectToJson(arrayStrings);    }    public static void testJsonToObject(String jsonString){        Gson gson = new Gson();        Bean2.Person fromJson = gson.fromJson(jsonString,Bean2.Person.class);        System.out.println(fromJson);                    }    public static void testObjectToJson(String json) {        Gson gson = new Gson();        Bean2 bean2 = gson.fromJson(json,Bean2.class);        System.out.println(bean2);        System.out.println(bean2.list);            }    //使用TypeToken解析成集合    public static void tokenObjectToJson(String json) {        //在值为空的时候也保留该字符串        Gson gson = new GsonBuilder().serializeNulls().create();        Type type = new TypeToken
    
     
      >(){}.getType();        Object fromJson = gson.fromJson(json,type);        System.out.println(fromJson);        String json2 = gson.toJson(fromJson);//生成json数据        System.out.println(json2);            }} class Bean2 {    List
      
        list;    public class Person {        public String name;        public int age;        public String address;        public String colorString;//增加属性,json字段中没有        public int height;//增加属性,json字段中没有        @Override        public String toString() {            return "Person [name=" + name + ", age=" + age + ", address="                    + address + ", colorString= "+colorString+", height ="+height+"]";        }    }    @Override    public String toString() {        return "Bean2 [list=" + list + ", getClass()=" + getClass()                + ", hashCode()=" + hashCode() + ", toString()="                + super.toString() + "]";    }    }