Double d= new Double(i);//first way  

Double d2=Double.valueOf(i);//second way  

// Primitive type

int myInt = 5;

double myDouble = (double)myInt;        // explicit cast

myDouble = myInt;                       // implicit cast

// Object type

Double myDouble = new Double(myInt)     // via constructor

myDouble = Double.valueOf(myInt)        // via valueOf

int integerValue = 10;

double doubleValue = (double) integerValue;

​

System.out.println("Integer value: " + integerValue);

System.out.println("Double value: " + doubleValue);

double d=i;