Why the output is showing the null values?

import java.io.*;
public class Employee {

   public String name;

   private double salary;

   public Employee (String empName) {
      name = empName;
   }
   public Employee (double empSal) {
      salary = empSal;
   }

   public void printEmp() {
      System.out.println("name  : " + name );
      System.out.println("salary :" + salary);
   }

   public static void main(String args[]) {
     Employee empOne = new Employee("Ransika");
     Employee emptwo = new Employee(1000);
      empOne.printEmp();
      emptwo.printEmp();
   }
}

$javac Employee.java
$java -Xmx128M -Xms16M Employee
name  : Ransika
salary :0.0
name  : null
salary :1000.0