getClass()与getName()和getSimpleName()的区别 getClass()和getSimpleName()的区别和作用

接口：

复制代码package com.test; public interface Fruit { }

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package com.test;

public interface Fruit {

}

一个实现类：

复制代码package com.test; public class Apple implements Fruit { }

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package com.test;

public class Apple implements Fruit {

}

基本测试类

复制代码package com.test; import java.util.ArrayList; import java.util.List; public class TestName { public static void main(String[] args) { Fruit apple=new Apple(); System.out.println(apple.getClass().getCanonicalName());//返回com.test.Apple System.out.println(apple.getClass().getSimpleName());//Apple System.out.println(apple.getClass().getName());//返回com.test.Apple Apple[] arrApple=new Apple[]{}; System.out.println(arrApple.getClass().getCanonicalName());//返回com.test.Apple[] System.out.println(arrApple.getClass().getSimpleName());//返回Apple[] System.out.println(arrApple.getClass().getName());//返回[Lcom.test.Apple; System.out.println(String.class.getCanonicalName());//返回java.lang.String System.out.println(String.class.getSimpleName());//返回String System.out.println(String.class.getName());//返回java.lang.String System.out.println(int.class.getCanonicalName());//返回int System.out.println(int.class.getSimpleName());//返回int System.out.println(int.class.getName());//返回int Apple a1=new Apple(); Apple a2=new Apple(); List<Apple> appleList=new ArrayList<Apple>(); appleList.add(a1); appleList.add(a2); System.out.println(appleList.getClass().getCanonicalName());//返回java.util.ArrayList System.out.println(appleList.getClass().getSimpleName());//返回ArrayList System.out.println(appleList.getClass().getName());//返回java.util.ArrayList } }

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package com.test;

import java.util.ArrayList;
import java.util.List;

public class TestName {
    public static void main(String[] args) {
        Fruit apple=new Apple();
        System.out.println(apple.getClass().getCanonicalName());//返回com.test.Apple
        System.out.println(apple.getClass().getSimpleName());//Apple
        System.out.println(apple.getClass().getName());//返回com.test.Apple
        
        Apple[] arrApple=new Apple[]{};
        System.out.println(arrApple.getClass().getCanonicalName());//返回com.test.Apple[]
        System.out.println(arrApple.getClass().getSimpleName());//返回Apple[]
        System.out.println(arrApple.getClass().getName());//返回[Lcom.test.Apple;
        
        System.out.println(String.class.getCanonicalName());//返回java.lang.String
        System.out.println(String.class.getSimpleName());//返回String
        System.out.println(String.class.getName());//返回java.lang.String
        
        System.out.println(int.class.getCanonicalName());//返回int
        System.out.println(int.class.getSimpleName());//返回int
        System.out.println(int.class.getName());//返回int
        
        Apple a1=new Apple();
        Apple a2=new Apple();
        List<Apple> appleList=new ArrayList<Apple>();
        appleList.add(a1);
        appleList.add(a2);
        System.out.println(appleList.getClass().getCanonicalName());//返回java.util.ArrayList
        System.out.println(appleList.getClass().getSimpleName());//返回ArrayList
        System.out.println(appleList.getClass().getName());//返回java.util.ArrayList
        
    }
}