Why is my loop not printing the first line of the loop after the first iteration?

Question

I'm trying to create a loop that repeats itself till an eof command is entered. The loop works, but the first line of my loop is not being printed, and would only appear after I enter my first input.

This is what I have for my loop:

do {

    System.out.print("Name: ");
    name = sc.nextLine();
    System.out.println("Name is \"" + name + "\"");
    numChild++;

    System.out.print("Age: ");
    age = sc.nextInt();
    System.out.println("Age is " + age);
    totalAge += age;

    System.out.print("Vaccinated for chickenpox? ");
    vac = sc.nextBoolean();
    sc.nextLine();

    if (vac) {

    System.out.println("Vaccinated for chickenpox");
    numVac++;
    } else {

    System.out.println("Not vaccinated for chickenpox");
    }
} while (sc.hasNext());

Shouldn't the output be back to "Name: " after the if-else statement is printed out? However, nothing is printed out till I enter another keyboard input, and the next line I would see is "Name: Name is "a""

Java console IO isn't flushed until a newline is printed. You'll have to flush the line manually. — markspace, Apr 27 '19 at 16:39
Possible duplicate of [Scanner is skipping nextLine() after using next() or nextFoo()?](https://stackoverflow.com/questions/13102045/scanner-is-skipping-nextline-after-using-next-or-nextfoo) — takendarkk, Apr 27 '19 at 16:39
How do I go about flussing the line. Relatively new to java, with experience only in c. — Glowing Snowman, Apr 27 '19 at 16:44
On a side note, you might want to change `System.out.println("Name is \"" + name + "\"");` to `System.out.println("\nName is \"" + name + "\"");` or `System.out.println("\rName is \"" + name + "\"");`. — Cardinal System, Apr 27 '19 at 16:46

score 0 · Answer 1 · answered Apr 27 '19 at 16:44

0

Try flushing the PrintStream:

do {
    System.out.print("Name: ");
    System.out.flush();
    // ... etc.

answered Apr 27 '19 at 16:44

markspace

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Why is my loop not printing the first line of the loop after the first iteration?

1 Answers1