Java program converts double type variables to int

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In this program, we will learn how to convert a double precision double variable to an integer (int) in Java.

To understand this example, you should understand the followingJava programmingTopic:

• Java variables and (original) data types

Example1: Java program using type conversion to convert double to int

class Main {
　　public static void main(String[] args) {
　　　　//Create a double variable
　　　　double a =　23.78D;
　　　　double b =　52.11D;
　　　　//Convert double to int
　　　　//Use explicit type conversion
　　　　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. Note this line,

int c = (int)a;

In this case, the higher double data type will be converted to the lower int data type. Therefore, we need to explicitly use int in parentheses.

This is calledNarrowing type conversion. For more information, please visitJava Type Conversion.

Note: When the value of double is less than or equal to int(2147483647). This process is effective when the maximum value is reached. Otherwise, there may be a loss of data due to truncation.

Example2: Use Math.round() to convert double to int

We can also use the Math.round() method to convert a double type variable to an int type variable. For example,

class Main {
　　public static void main(String[] args) {
　　　　//Create a double variable
　　　　double a =　99.99D;
　　　　double b =　52.11D;
　　　　//Convert double to int
　　　　//Use type conversion
　　　　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 created two double type variables named a and b. Note this line,

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

Here,

• Math.round(a) -　 Convert a decimal value to a long value

• (int) -　 Convert a long value to an int value using type conversion

The Math.round() method rounds a decimal value to the nearest long value. For more information, please visit　 Java Math round().

Example3: Java Program to Convert Double to int

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

class Main {
　　public static void main(String[] args) {
　　　　//Create an instance of Double
　　　　Double obj =　78.6;
　　　　//Convert obj to int
　　　　//Use intValue()
　　　　int num = obj.intValue();
　　　　//Print int value
　　　　System.out.println(num);　　　　//　78
　　{}
{}

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

Here, Double is a Java wrapper class. For more information, please visitJava Wrapper Classes.

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