Check out example codes for "how to change double to int in java". It will help you in understanding the concepts better.

Code Example 1

class Scratch{
    public static void main(String[] args){
        double decimal = 5.7;
        System.out.println( (int) decimal );	//casting
        System.out.println( Math.round(decimal * 10) / (double) 10);	//Math.round()
        System.out.println( decimal % 1);	// modulus
        System.out.println( Integer.parseInt( String.valueOf(decimal).substring(0, String.valueOf(decimal).indexOf(".")))); // .substring()
    }
}

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