import java.util.*;

public class Test {

    public static void main(String[] args) {
        int a=0;
        Scanner input = new Scanner(System.in);
        System.out.println("请输入月份：");
        do {
            a = input.nextInt();
            if(a>12||a<1){
                System.out.println("输入错误，请重新输入:");
            }
            else{
                break;
            }
        } while (true);
        switch (a) {
            case 1:
            case 2:
            case 3:
                System.out.println("春天");
                break;
            case 4:
            case 5:
            case 6:
                System.out.println("夏天");
                break;
            case 7:
            case 8:
            case 9:
                System.out.println("秋天");
                break;
            case 10:
            case 11:
            case 12:
                System.out.println("冬天");
                break;
        }
    }
}

------解决方案--------------------
if(a>0&&a<13)
{
   if(a<=6)  
   {
       if(a<=3) System.out.println("春天");  
       else System.out.println("夏天");
   }
   else  
   { 
       if(a<=9) System.out.println("秋天");
       else System.out.println("冬天");
   }
}
else System.out.println("输入有误！");



循环这样的话，会比较简洁点

------解决方案--------------------
public class Suilian4 {
public static void main(String[] args) {
int a;
Scanner input = new Scanner(System.in);
System.out.println("请输入月份：");
a = input.nextInt();
while(a<0||a>13){//加一个while循环判断输入的月份是否在范围之内，不在范围之内循环再次输入
	System.out.println("输入错误，请重新输入：");
	System.out.println("请输入月份：");
	a = input.nextInt();
	break;
}
switch (a) {
case 1:
case 2:
case 3:
System.out.println("春天");
break;
case 4:
case 5:
case 6:
System.out.println("夏天");
break;
case 7:
case 8:
case 9:
System.out.println("秋天");
break;
case 10:
case 11:
case 12:
System.out.println("冬天");
break;
}
}

}