import java.io.BufferedReader;
import java.io.IOException;
import java.io.InputStreamReader;
public class DecimalToBinary
{

    public static void main(String args[]) throws Exception, IOException
    {
        int a;
        int i = 0;
        int b[] = new int[10];
        BufferedReader br = new BufferedReader(new InputStreamReader(System.in));
        System.out.print("Enter any Decimal value: ");
        a=Integer.parseInt(br.readLine());

        while (a != 0)
        {
            i++;
            b[i] = a % 2;
            a = a / 2;
        }
        System.out.println("the binary value for the given decimal is: ");
        for (int j = i; j > 0; j--)
        {

            System.out.print(b[j]);
        }
    }
}

 OUTPUT:

   
C:\java>javac DecimalToBinary.java

C:\java>java DecimalToBinary
Enter any Decimal value: 12
the binary value for the given decimal is:
1100

In output C:\java is a folder name. Program Tested in Windows 7 Command Prompt and java version "1.7.0_03"