Please help me with this for loop with Scanner next() vs nextLine()

[milk242]

import java.util.Scanner;
public class DogDemo
{
	public static void main(String[] args)
	{
		Dog myDog[] = new Dog[2];
		Scanner keyboard = new Scanner(System.in);
		String name, breed;
		int age;
		boolean boost;
		
		for (int i = 0; i < myDog.length; i++)
		{
			System.out.println("Dog " +i + " information.");
			System.out.println("Dog's name?");
			name = keyboard.nextLine();
			System.out.println("Dog's breed?");
			breed = keyboard.nextLine();
			System.out.println("Dog's age?");
			age = keyboard.nextInt();
			System.out.println("Dog's boostershot (true or false)");
			boost = keyboard.nextBoolean();
			/*if (ans == "yes")
				boost = true;
			else
				boost = false;*/
				
			myDog[i] = new Dog(name, breed, age, boost);
		}
		
		System.out.println("\nDog's information\n");
		for (int i = 0; i < myDog.length; i++)
		{
			System.out.println("Name: " + myDog[i].getName());
			System.out.println("Breed: " + myDog[i].getBreed());
			System.out.println("Age: " + myDog[i].getAge());
			System.out.println("Booster: " + myDog[i].getBoosterShot());
			System.out.println();			
		}
		
	}
}

Output:

Dog 0 information.
Dog's name?
Minnie
Dog's breed?
York
Dog's age?
2
Dog's boostershot (true or false)
true
Dog 1 information.
Dog's name?
Dog's breed?

My question... why does it skip Dog's name after it loops once? It doesn't allow me to enter the second dog's name just skips to breed. I know it has something to do with Scanner method next() vs nextLine() but I'm not sure. I made the strings read next() before and it worked correctly, but when it comes time to enter a breed that is two words, it won't take. Thanks!

[JosAH]

The nextInt() and nextBoolean() etc. methods don't read beyond what they have to read. If, say, an int has to be read and you type 123<enter> the int 123 is read and the newline character (caused by the <enter> key) is left in the input buffer.

If you want to read an entire line afterwards, a new line character is seen and an empty line is returned. This looks as if nothing is read. The cure is simple: add a spurious readLine() method that gets rid of that one new line character and brings you 'in sync' again. Remember that the <enter> key puts a new line character in the input buffer and you have to deal with it one way or another.

kind regards,

Jos

[milk242]

Thanks! that was a great explanation. That really helped me.