在java中扩展的通用方法 [英] Generic method with extend in java

问题描述

我有一个通用方法的TestClass类。但是当我用这些参数运行
method1时，它执行得很好。
我错过了什么吗？应该method1抛出异常，因为对象不扩展Integer？

I have the class TestClass with a generic method. But when i run the method1 with those arguments it executes fine. Am i missing something? Should method1 throw exception because object does not extend Integer?

 TestClass i = new TestClass();
 i.method1(new Object(), new Integer(2));


  public class TestClass {

        protected final int testClassvar1=2;

        public <E,T extends E> void method1(T t,E e) {
        System.out.println(e.getClass()); 
       }
   }

推荐答案

强制约束T在编译时扩展E，当您调用需要指定将替换参数化类型的类型的方法时。

To enforce the constraint T extends E at compile time, when you call the method you need to specify the types that will replace the parameterized types. Otherwise, both types are assumed to be Object.

i.<Object,Integer>method1(new Object(), new Integer(2));

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