java - switch block try/catch exception -


this question has answer here:

i have switch statement 5 integer options , default message. trying work if other choice numbers chosen, "invalid input" message show up. works numbers, if else entered, following exception:

exception in thread "main" java.util.inputmismatchexception

i tried add try/catch statement, doesn't seem working; keep getting same error message.

public static void main(string[] args) throws ioexception {     int menuitem = -1;     while (menuitem != 0) {         menuitem = menu();         try {             switch (menuitem) {                 case 1:                     showtasklist();                     break;                 case 2:                     addtask();                     break;                 case 3:                     sortlist();                     break;                 case 4:                     deletetasks();                     break;                 case 0:                     break;                 default:                     system.out.println("invalid input");                     break;             }         }         catch (java.util.inputmismatchexception err) {             system.out.println("\ninvalid input!");         }     } }

if program terminates java.util.inputmismatchexception follows that exception not thrown within try block presented. inasmuch exception associated entering input in unexpected form, , inasmuch attempt convert input number evidently has been performed in method menu(), before entering try block, seems reasonable conclude exception thrown method menu(). stack trace accompanying exception have told directly, , more precisely can presented.

based on nature of task , type of exception received, speculate using scanner read user input, , invoking scanner.nextint(). method throw exception of type specified if invoked when next token cannot interpreted java int.

only can decide how best deal that, 1 possibility move invocation of menu() method inside try block:

    // ...     while (menuitem != 0) {         try {             menuitem = menu();             switch (menuitem) {             // ...

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