What is the nextInt() Method in Java?
Example 1
Let’s take our first dive to the basic example.
import java.util.Scanner;
public class TestIntInput {
public static void checkInt(String testData) {
System.out.println(testData);
Scanner scanner = new Scanner(testData);
while (scanner.hasNext()) {
if (scanner.hasNextInt()) {
// calling the nextInt() method
System.out.println(scanner.nextInt() + "\t\t INT FOUND!");
} else {
System.out.println(scanner.next() + "\t\t");
}
}
scanner.close();
System.out.println();
}
public static void main(String[] args) {
String testData1 = "My 3 years old cat Diana, just gave birth to 5 healthy babies.";
String testData2 = "The number 1 place to learn Java is CodeGym!";
String testData3 = "6; 5 4 3. 2 1 !";
checkInt(testData1);
checkInt(testData2);
checkInt(testData3);
}
}
Output
My 3 years old cat Diana, just gave birth to 5 healthy babies.
My
3 INT FOUND!
years
old
cat
Diana,
just
gave
birth
to
5 INT FOUND!
healthy
babies.
The number 1 place to learn Java is CodeGym!
The
number
1 INT FOUND!
place
to
learn
Java
is
CodeGym!
6; 5 4 3. 2 1 !
6;
5 INT FOUND!
4 INT FOUND!
3.
2 INT FOUND!
1 INT FOUND!
!
Explanation
One thing to note in the above example in testData3 is that a number needs to be space-separated to be scanned as an individual int. That’s the reason why 6 and 3 are not identified as integers because they are colon and comma-separated respectively.Example 2
This example uses the System input to scan it as integers.
import java.util.Scanner;
public class TestSystemInput {
public static void getFinalExamScore() {
System.out.println("Get Your Final Exam Score!\n");
int finalScore = 0;
int totalCourses = 0;
Scanner scanner = new Scanner(System.in);
System.out.println("Enter total Courses: ");
totalCourses = scanner.nextInt();
for (int i = 0; i < totalCourses; i++) {
System.out.println("Enter score in course " + (i + 1) + " : ");
finalScore = finalScore + scanner.nextInt();
}
System.out.println("Your final Score = " + finalScore);
scanner.close();
}
public static void main(String[] args) {
getFinalExamScore();
}
}
Output
Get Your Final Exam Score!
Enter total Courses:
3
Enter score in course 1 :
10
Enter score in course 2 :
15
Enter score in course 3 :
15
Your final Score = 40
Conclusion
That’s a wrap for the nextInt() method by Scanner class in Java. It can be a little overwhelming at first but practise will keep you afloat. Feel free to hop on in case of any ambiguity. We encourage you to play around with different input methods for a better understanding. Happy learning!
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