Generic 泛型 在method 中 传参的使用
1 import java.util.*; 2 3 4 /** 5 * Created by wojia on 2017/6/14. 6 */ 7 public class App { 8 public static void main(String args[]){ 9 /**that means the tyoe of data being sended to generic must be String type*/ 10 genericDemo<String> generic = new genericDemo<String>(); 11 //clone 12 String temp = generic.send( "testing" ); 13 System.out.println(temp); 14 //restricted in Integer type 15 ArrayList<Integer> list2 = new ArrayList<>(); 16 list2.add( 1111 ); 17 /** the type is determined as Integer!! */ 18 doWork( list2 ); 19 } 20 21 /** 22 * <?> means the type is up to caller 23 * 24 * */ 25 public static ArrayList<?> doWork(ArrayList<?> list){ 26 ArrayList<?> list1 = new ArrayList<>(); 27 // acturally the below operation just pass the address(hashSet) 28 list1 = list; 29 System.out.println(list1); 30 return list1; 31 } 32 }
如上
