Java custom generic interview questions: receive any array to reverse, java custom

Java custom generic interview questions: receive any array to reverse, java custom

You can only operate on a certain type for reversal without using the generic type.

The Code is as follows:

package com.swift.fanxing;import org.junit.Test;public class RenyiReverse {    @Test    public void test() {        int arr[]=new int[] {1,10,6,9,2};        reverse(arr);    }        public void reverse(int[] arr) {                for(int i=0;i<arr.length/2;i++) {                        int temp=arr[i];            arr[i]=arr[arr.length-1-i];            arr[arr.length-1-i]=temp;        }                for(int x:arr) {            System.out.println(x);        }    }}

In addition to applications on the set iterator, the generic function can also receive variables or arrays of any type of classes.

Package com. swift. fanxing; import org. junit. test; public class RenyiReverse {@ Test public void test () {Integer arr [] = new Integer [] {1, 10, 6, 9, 2 }; // here, you cannot use int to replace Integer String arr2 [] = new String [] {"aa", "bb", "cc", "dd", "ee "}; reverse (arr); reverse (arr2);} public <T> void reverse (T [] arr) {for (int I = 0; I <arr. length/2; I ++) {T temp = arr [I]; arr [I] = arr [arr. length-1-i]; arr [arr. length-1-i] = temp;} for (T x: arr) {System. out. println (x );}}}

Non-static declaration is in place, static declaration is in place, and class declaration is global. For multi-generic declaration, <T, J, K>