java - Using scanner.nextLine() -

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• scanner skipping nextline() after using next(), nextint() or other nextfoo()? 12 answers

i have been having trouble while attempting use nextline() method java.util.scanner.

here tried:

import java.util.scanner;  class testrevised {     public void menu() {         scanner scanner = new scanner(system.in);          system.out.print("enter sentence:\t");         string sentence = scanner.nextline();          system.out.print("enter index:\t");         int index = scanner.nextint();          system.out.println("\nyour sentence:\t" + sentence);         system.out.println("your index:\t" + index);     } } 

example #1: example works intended. line string sentence = scanner.nextline(); waits input entered before continuing on system.out.print("enter index:\t");.

this produces output:

enter sentence:   hello. enter index: 0  sentence:  hello. index: 0 

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// example #2 import java.util.scanner;  class test {     public void menu() {         scanner scanner = new scanner(system.in);          while (true) {             system.out.println("\nmenu options\n");             system.out.println("(1) - this");             system.out.println("(2) - quit");              system.out.print("please enter selection:\t");             int selection = scanner.nextint();              if (selection == 1) {                 system.out.print("enter sentence:\t");                 string sentence = scanner.nextline();                  system.out.print("enter index:\t");                 int index = scanner.nextint();                  system.out.println("\nyour sentence:\t" + sentence);                 system.out.println("your index:\t" + index);             }             else if (selection == 2) {                 break;             }         }     } } 

example #2: example not work intended. example uses while loop , and if - else structure allow user choose do. once program gets string sentence = scanner.nextline();, not wait input instead executes line system.out.print("enter index:\t");.

this produces output:

menu options  (1) - (2) - quit  please enter selection:    1 enter sentence:   enter index:  

which makes impossible enter sentence.

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why example #2 not work intended? difference between ex. 1 , 2 ex. 2 has while loop , if-else structure. don't understand why affects behavior of scanner.nextint().

i think problem that

int selection = scanner.nextint(); 

reads number, not end of line or after number. when you

string sentence = scanner.nextline(); 

this read remainder of line number on (with nothing after number suspect)

try placing scanner.nextline(); after each nextint() if intend ignore rest of line.