Java Program to convert double type variables to int

Java Program to convert double type variables to int

In this program, we will learn to convert the double variables into the integer (int) in Java.

Example 1: Java Program to Convert double to int using Typecasting

class Main {
  public static void main(String[] args) {

    // create double variables
    double a = 23.78D;
    double b = 52.11D;

    // convert double into int
    // using typecasting
    int c = (int)a;
    int d = (int)b;

    System.out.println(c);    // 23
    System.out.println(d);    // 52
  }
}

In the above example, we have double type variables a and b. Notice the line,

int c = (int)a;

Here, the higher data type double is converted into a lower data type int. Hence, we need to explicitly use int inside the bracket.

This is called narrowing typecasting. To learn more, visit Java Typecasting.

Note: This process works when the value of double is less than or equal to the maximum value of int (2147483647). Otherwise, there will be a loss in data.


Example 2: Java Program to Convert double to int using Math.round()

We can also convert the double type variable into int using the Math.round() method. For example,

class Main {
  public static void main(String[] args) {

    // create double variables
    double a = 99.99D;
    double b = 52.11D;

    // convert double into int
    // using typecasting
    int c = (int)Math.round(a);
    int d = (int)Math.round(b);

    System.out.println(c);    // 100
    System.out.println(d);    // 52
  }
}

In the above example, we have created two double variables named a and b. Notice the line,

int c = (int)Math.round(a);

Here,

  • Math.round(a) - converts the decimal value into long value
  • (int) - converts the long value into int using typecasting

The Math.round() method rounds the decimal value to the closest long value. To learn more, visit the Java Math round().


Example 3: Java Program to Convert Double to int

We can also convert an instance of Double class to int using the intValue() method. For example,

class Main {
  public static void main(String[] args) {

    // create an instance of Double
    Double obj = 78.6;

    // convert obj to int
    // using intValue()
    int num = obj.intValue();

    // print the int value
    System.out.println(num);    // 78
  }
}

Here, we have used the intValue() method to convert the object of Double to int.

The Double is a wrapper class in Java. To learn more, visit the Java Wrapper Class.