public void setRoundingMode(RoundingMode mode)

// Java program to implement
// the above function
 
import java.text.NumberFormat;
import java.util.Locale;
import java.util.Currency;
import java.math.RoundingMode;
 
public class Main {
    public static void main(String[] args)
        throws Exception
    {
 
        NumberFormat nF
            = NumberFormat.getNumberInstance();
 
        System.out.println("set initially as: "
                           + nF.getRoundingMode());
 
        // Set grouping
        nF.setRoundingMode(RoundingMode.FLOOR);
 
        // Print the final
        System.out.println("set finally as: "
                           + nF.getRoundingMode());
    }
}

set initially as: HALF_EVEN
set finally as: FLOOR

// Java program to implement
// the above function
 
import java.text.NumberFormat;
import java.util.Locale;
import java.util.Currency;
import java.math.RoundingMode;
 
public class Main {
    public static void main(String[] args)
        throws Exception
    {
 
        NumberFormat nF
            = NumberFormat.getNumberInstance();
 
        System.out.println("set initially as: "
                           + nF.getRoundingMode());
 
        // Set grouping
        nF.setRoundingMode(RoundingMode.DOWN);
 
        // Print the final
        System.out.println("set finally as: "
                           + nF.getRoundingMode());
    }
}

set initially as: HALF_EVEN
set finally as: DOWN

// Java program to implement
// the above function
 
import java.text.NumberFormat;
import java.util.Locale;
import java.util.Currency;
import java.math.RoundingMode;
 
public class Main {
    public static void main(String[] args)
        throws Exception
    {
        try {
 
            NumberFormat nF
                = NumberFormat.getNumberInstance();
 
            System.out.println("set initially as: "
                               + nF.getRoundingMode());
 
            // Set grouping
            nF.setRoundingMode(null);
 
            // Print the final
            System.out.println("set finally as: "
                               + nF.getRoundingMode());
        }
        catch (Exception e) {
            System.out.println("Exception is: "
                               + e);
        }
    }
}

set initially as: HALF_EVEN
Exception is: java.lang.NullPointerException