Java开关盒

当我进入子菜单并完成（例如案例1）时，案例完成后，它会自动跳转到主菜单的案例2，有人能告诉我如何停止，因为我希望它只是再次显示主菜单吗

switch (choice) {
    case 1:    //finish add passenger
        System.out.println(" 1 - Add passenger");
        System.out.println(mySubMenu.displayMenu());
        int subChoice = mySubMenu.getChoice();
        switch (subChoice) {
            case 1:
                try {
                    System.out.println("Please enter the passengers forename");
                    String aforename = strKeyB.next();
                    System.out.println("Please enter the passengers surname");
                    String surname = strKeyB.next();

                    System.out.println("Please enter the passengers nationality");
                    String nationality = strKeyB.next();

                    System.out.println("Please enter the passenger age");
                    int age = intKeyB.nextInt();
                    System.out.println(pass1.pasengerAdd(aforename, surname, nationality, age));
                    break;
                } catch (Exception ex) {
                    System.out.println(ex.toString());

                }

            case 2:
                try {
                    System.out.println("Please enter the passengers forename");
                    String onforename = strKeyB.next();
                    System.out.println("Please enter the passengers surname");
                    String onSurname = strKeyB.next();
                    pass1.pasengerAdd(onforename, onSurname);

                } catch (Exception ex) {
                    System.out.println(ex.toString());

                }
                break;
            case 3:
                try {
                    System.out.println("Please enter the passengers forename");
                    String nnforename = strKeyB.next();
                    System.out.println("Please enter the passengers surname");
                    String nnSurname = strKeyB.next();
                    System.out.println("Please enter the passengers age");
                    int intAge = intKeyB.nextInt();
                    pass1.pasengerAdd(nnforename, nnSurname, intAge);


                } catch (Exception ex) {
                    System.out.println(ex.toString());

                }//end catch 
                break;
            case 4:
                try {
                    System.out.println("Please enter the passengers forename");
                    String naforename = strKeyB.next();
                    System.out.println("Please enter the passengers surname");
                    String naSurname = strKeyB.next();
                    System.out.println("Please enter the passengers nationality");
                    String naNat = strKeyB.next();
                    pass1.pasengerAdd(naforename, naSurname, naNat);

                } catch (Exception ex) {
                    System.out.println(ex.toString());

                }
                break;
            case 5:
                System.out.println(myMenu.displayMenu());
                break;
        }//end sub menu switch


    case 2:
        try {
            System.out.println(" 2 - Delete Passenger");
            System.out.println("Please enter the passenger forename ");
            String dForename = strKeyB.next();
            System.out.println("Please enter the passenger surname ");
            String dSurname = strKeyB.next();
            System.out.println(pass1.passengerDelete(dForename, dSurname));
        } catch (Exception ex) {
            System.out.println(ex.getMessage());
        }

        break;
}

---

在每个

案例的末尾使用
break

这里的问题是您有两个
案例1:
：


案例1：在
开关（选择）
案例1：在
开关（子选择）

你错过了两件事：


switch（choice）
中的
break
语句，因此将执行
案例2中的代码：
开关（子选择）
中的
案例1:
的catch分支

看看这个简单的例子：

switch(choice) {
case 1:
    // code1
    break;
case 2: 
    // code2
    break;
}

在这里，案例代码将单独执行

否则，在本规范中：

switch(choice) {
case 1:
    // code1
case 2: 
    // code2
}

当不使用
break
时，代码将继续执行，因此当
choice==1
code1
和
code2
时，将执行。但是如果
choice==2
只执行
code2
。当两个或多个选项共享某些代码时，这是非常有用的

注意：这也是有效的：

switch(choice) {
case 1:
case 2: 
    // code1
    // code2
    break;
}

在此语句中，
case1
和
case2
将执行相同的代码


解决方案：
了解这一点后，您的代码必须有两个修复：

将
break
语句插入
switch（choice）
中的
case2:
将
开关（子选择）
中
案例1:
的
break
语句移到末尾，就在
案例2:

尝试使用中断标签中断外部开关语句。或者在内部开关语句之后放置break。更简单的是。
switch (choice) {
case 1:    //finish add passenger
    System.out.println(" 1 - Add passenger");
    System.out.println(mySubMenu.displayMenu());
    int subChoice = mySubMenu.getChoice();
    switch (subChoice) {
        case 1:
            try {
                System.out.println("Please enter the passengers forename");
                String aforename = strKeyB.next();
                System.out.println("Please enter the passengers surname");
                String surname = strKeyB.next();

                System.out.println("Please enter the passengers nationality");
                String nationality = strKeyB.next();

                System.out.println("Please enter the passenger age");
                int age = intKeyB.nextInt();
                System.out.println(pass1.pasengerAdd(aforename, surname, nationality, age));
            } catch (Exception ex) {
                System.out.println(ex.toString());

            }
            break;  // here you miss case 1: in switch(subchoice) when exception

        case 2:
            try {
                System.out.println("Please enter the passengers forename");
                String onforename = strKeyB.next();
                System.out.println("Please enter the passengers surname");
                String onSurname = strKeyB.next();
                pass1.pasengerAdd(onforename, onSurname);

            } catch (Exception ex) {
                System.out.println(ex.toString());

            }
            break;

//
// more code until...
//

break; 

case 2:  // here you miss case 1: in switch(choice) 
    try {
        System.out.println(" 2 - Delete Passenger");