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@PandyYang
Created May 13, 2018 09:38
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package jichubiancheng;
import java.util.ArrayList;
/**
* @author Pandy
* @date 2018/5/13 16:18
*/
public class ApplesAndOrangesWithGenerics {
public static void main(String[] args){
//这块使用了泛型 <>之间是类型参数 指定了这个容器实例可以保存的类型
ArrayList<Apple> apples = new ArrayList<Apple>();
for (int i = 0;i<3;i++)
apples.add(new Apple());
//apples.add(new Orange()); 由于增加了泛型 规定了容器保存的类型 所以这个语句在编译时期就会出错
for (int i = 0;i<apples.size();i++)
System.out.println(apples.get(i).id());
for (Apple c : apples)
System.out.println(c);
}
}
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