public static DataType abs(DataType a)

// Java Program to Illustrate Absolute Method
// of Math Class
 
// Importing all Math classes
// from java.lang package
import java.lang.Math;
 
// Main class
class GFG {
   
    // Main driver method
    public static void main(String[] args)
    {
 
        // Custom integer input received from user
        int n = -7;
 
        // Printing value before applying absolute function
        System.out.println(
            "Without applying Math.abs() method : " + n);
 
        // Applying absolute math function and
        // storing it in integer variable
        int value = Math.abs(n);
 
        // Printing value after applying absolute function
        System.out.println(
            "With applying Math.abs() method : " + value);
    }
}

Without applying Math.abs() method : -7
With applying Math.abs() method : 7

// Java Program to Demonstrate Working of abs() method
// of Math class inside java.lang package
 
// Importing Math class
// from java.lang package
import java.lang.Math;
 
// Main class
class GFG {
 
    // Main driver method
    public static void main(String args[])
    {
        // Customly declaring and initializing all
        // arguments that ans() function takes
 
        // Float
        float a = 123.0f;
        float b = -34.2323f;
 
        // Double
        double c = -0.0;
        double d = -999.3456;
 
        // Integer
        int e = -123;
        int f = -0;
 
        // Long
        long g = -12345678;
        long h = 98765433;
 
        // abs() method taking float type as input
        System.out.println(Math.abs(a));
        System.out.println(Math.abs(b));
 
        // abs() method taking double type as input
        System.out.println(Math.abs(1.0 / 0));
        System.out.println(Math.abs(c));
        System.out.println(Math.abs(d));
 
        // abs() method taking int type as input
        System.out.println(Math.abs(e));
        System.out.println(Math.abs(f));
        System.out.println(Math.abs(Integer.MIN_VALUE));
 
        // abs() method taking long type as input
        System.out.println(Math.abs(g));
        System.out.println(Math.abs(h));
        System.out.println(Math.abs(Long.MIN_VALUE));
    }
}

123.0
34.2323
Infinity
0.0
999.3456
123
0
-2147483648
12345678
98765433
-9223372036854775808