在java中循环返回

Question

我在Java（netbeans）中循环返回时遇到问题。
我必须创建4个类，“循环”部分是唯一未完成的部分。

package question.pkg1; 

import java.util.Scanner; 
public class Shape { 

void secondclass(){ 

System.out.println("Choose the shape you want to find the Perimeter and Area of: "); 
System.out.println("1. Square " 
         + " 2. Rectangle "); 
System.out.println("**To select sqauare, enter 1**"); 
System.out.println("**To select rectangle, enter 2**"); 

int value; 

Scanner input = new Scanner(System.in); 
value = input.nextInt(); 

if (value == 1) { 
    Square Squareclass = new Square(); 
    Squareclass.thirdclass();} 

else if (value == 2) { 
    Rectangle Rectangleclass = new Rectangle(); 
    Rectangleclass.fourthclass();} 

else{ 
    System.out.println("**Error: Please enter a correct value!**"); 
} 

}} 

Answer 1

使用do ... while循环，如：

do { 
    //read value 
    //process based on value 
} while (value > 0 && value <= 2);//assuming your valid values are 1,2 and if it is let user continue further.