Java泛型---泛型的巢狀
阿新 • • 發佈:2019-02-07
泛型巢狀的使用
建立一個PO類
/**
* 測試泛型的巢狀
* @author Administrator
*
* @param <T>
*/
public class Class01<T> {
private T stu;
public T getStu() {
return stu;
}
public void setStu(T stu) {
this.stu = stu;
}
}
泛型的巢狀使用及HashMap中的典型泛型巢狀使用方法
import java.util.HashMap; import java.util.Map; import java.util.Set; import java.util.Map.Entry;; /** * 泛型的巢狀 --->由外向內拆分 * @author Administrator * */ public class Generics { public static void main(String[] args) { Student01<String> stu = new Student01<String>(); stu.setScore("AA"); System.out.println(stu.getScore()); //巢狀 --->多層包裹 Class01<Student01<String>> c1 = new Class01<Student01<String>>(); c1.setStu(stu); stu = c1.getStu(); String score = stu.getScore(); System.out.println(score); //HashMap中的泛型巢狀 Map<String, String> map = new HashMap<String, String>(); map.put("01", "AA"); map.put("02", "BB"); Set<Entry<String,String>> entrySet = map.entrySet(); //增強的for迴圈,遍歷entrySet for (Entry<String, String> entry : entrySet) { System.out.println(entry); String key = entry.getKey(); String value = entry.getValue(); System.out.println(key+"--->"+value); } } }