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一、自定义泛型类

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  1. package com.key.d15_packeg_03.fanxing;
  2. import java.util.ArrayList;
  3. public class MyArrayList<E> {
  4. private ArrayList list = new ArrayList();
  5. public void add(E e){
  6. list.add(e);
  7. }
  8. public void del(E e){
  9. list.remove(e);
  10. }
  11. @Override
  12. public String toString() {
  13. return list.toString();
  14. }
  15. }
  1. package com.key.d15_packeg_03.fanxing;
  2. public class Test {
  3. public static void main(String[] args) {
  4. //模拟ArrayList,定义一个MyArrayList,关注泛型方法
  5. MyArrayList<String> myArrayList = new MyArrayList<>();
  6. myArrayList.add("JAVA");
  7. myArrayList.add("Python");
  8. myArrayList.add("mysql");
  9. myArrayList.del("Python");
  10. System.out.println(myArrayList);
  11. System.out.println("--------------");
  12. }
  13. }

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二、自定义泛型方法

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三、自定义泛型接口

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四、泛型通配符,上下限