如何设法返回到行代码？

Question

在我的代码中，我如何才能返回到第一行代码。 这样输出将是：

您必须输入介于100和99999之间的值

写出您想发送多少个数据包：（介于100-99999之间）

2

您必须输入100到99999之间的值

写出您想发送多少个数据包：（介于100-99999之间）

200

因此，每次输入错误的数字时，都会显示第一行，直到正确为止。

    System.out.println("\n Write how much packets you want to send : (between 100 - 99999)");
    int min = 100;
    int max = 99999;
    int packets = scan.nextInt();

    if (packets >= min && packets <= max) {

        System.out.println("You have sended : " + packets + " packets");


        System.out.println("\n Attack is processing...");
        try {

            Thread.sleep(5000);
        }
        catch (InterruptedException ex)
        {

        }

        System.out.println("\n Attack is done");

        try {
            Thread.sleep(1000);
        }
        catch (InterruptedException ex)
        {

        }

    }else {

        System.out.println("You have to put a value between 100 and 99999");
        // Here I want to return to line 1
    }

Answer 1

尝试while循环。

boolean isRescanRequired = true;
while(isRescanRequired){
    // your scanning code goes here
    if (packets >= min && packets <= max) {
        // your processing and sleep code
        isRescanRequired = false;
    }
}