java对象转json，字段赋值

import com.alibaba.fastjson.annotation.JSONField;

public class test {
     private String name;
     private String test_age;

     public String getName() {
           return name;
     }  
      public void setName(String name) {
           this.name=name;
      }


     @JSONField(name = "age")
     public String getTest_age() {
           return test_age;
     }  
      public void setTest_age(String test_age) {
           this.test_age=test_age;
      }
}