java - java程序出错时如何保持运行

Question

我正在尝试制作一个java远程控制程序，通过客户端访问它，这是来自服务器的一些代码。我是编程新手，我需要一些帮助。 我希望我的服务器继续运行 -> 问题是，当我向 CmdMenuDecision 分配字符串值时，服务器崩溃。有办法解决吗？ 我还在 ,, int CmdMenuDecision = new Scanner(System.in).nextInt(); 处遇到内存泄漏,,,我使用@SuppressWarnings("resource")，我不确定它是否好。

private static Scanner SCANNER = new Scanner(System. in );
private String command1;
private String command2;
private String command3;
private String command4;

public void runtimeChoice() {
    System.out.println("what do you want to do? 1. Execute CMD Command");
    int CmdMenuDecision = new Scanner(System. in ).nextInt();
    switch (CmdMenuDecision) {
        case 1:
            CMDCommand();
            break;
        default:
            System.out.println("No valid answer");
            break;
    }
    private void CMDCommand() {
        System.out.println("CMD is working!");
        Runtime rt = Runtime.getRuntime();
        try {
            System.out.println("Insert desired command");
            command1 = CmdCommand.nextLine();
            command2 = CmdCommand.nextLine();
            command3 = CmdCommand.nextLine();
            command4 = CmdCommand.nextLine();
            rt.exec(new String[] {
                "cmd.exe", "/c", /*"start",*/
                command1, command2, command3, command4
            });
            System.out.println("Command: " + command1 + " " + command2 + " " + command3 + " " + command4 + " executed succesfully");
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
}

Answer 1

改变

int CmdMenuDecision = new Scanner(System.in).nextInt();

至

boolean flag = false;

do {
    try {
        int CmdMenuDecision = new Scanner(System.in).nextInt();
        flag = true; // If the execution flow reached this line then that means that the user input was correct; break the loop.
    }
    catch(InputMismatchException e) {
        System.out.println("Invalid input, try again.");
    }
}while(!flag);

这将确保您获得 CmdMenuDecision 变量的 Integer 输入。

当扫描器期望int输入String时，将抛出InputMismatchException；你需要处理它。