利用ParameterizedType获取泛型参数类型

https://www.cnblogs.com/baiqiantao/p/5373283.html

GenericsDemo.java

 1 import java.lang.reflect.ParameterizedType;
 2 import java.lang.reflect.Type;
 3 
 4 //利用ParameterizedType获取java泛型的参数类型
 5 
 6 public class GenericsDemo {
 7     public static void main(String[] args) {
 8         classTest();
 9         interfaceTest();
10     }
11     
12     private static void classTest() {
13         MySuperClass<Student, String> mySuperClass = new MySuperClass<Student, String>() {
14             @Override
15             public void onSuccess(Student data) {
16             }
17         };
18         //getClass().getGenericSuperclass()返回表示此 Class 所表示的实体的直接超类的 Type
19         ParameterizedType type = (ParameterizedType) mySuperClass.getClass().getGenericSuperclass();
20         sysoType(type);
21     }
22     
23     private static void interfaceTest() {
24         MyInterface<Student, String> myInterface = new MyInterface<Student, String>() {
25             @Override
26             public void onSuccess(Student data) {
27             }
28         };
29         ParameterizedType type = (ParameterizedType) myInterface.getClass().getGenericInterfaces()[0];
30         sysoType(type);
31     }
32     
33     private static void sysoType(ParameterizedType type) {
34         System.out.println(type + "\n" + type.getClass());
35         
36         //返回表示此类型实际类型参数的 Type 对象的数组，泛型的参数可能有多个，我们需要哪个就取哪个
37         Type[] targets = type.getActualTypeArguments();
38         for (int i = 0; i < targets.length; i++) {
39             System.out.println(targets[i] + "\n" + targets[i].getClass());
40         }
41     }
42 }

MyInterface.java

1 public interface MyInterface<T, V> {
2     void onSuccess(T data);
3 }

MySuperClass.java

1 public abstract class MySuperClass<T,V> {
2     public abstract void onSuccess(T data);
3 }

Student.java

1 public class Student {
2 
3 }

 GenericsDemo.rar

posted on 2018-12-20 18:19  eustoma  阅读(393)  评论(0)  编辑  收藏  举报

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