Conversion from Long to Double in Java

Is there any way to convert a Long data type to Double or double?

For example, I need to convert 15552451L to a double data type.

You could simply do :

double d = (double)15552451L;

Or you could get double from Long object as :

Long l = new Long(15552451L);
double d = l.doubleValue();

Simple casting?

double d = (double)15552451L;

As already mentioned, you can simply cast long to double. But be careful with long to double conversion because long to double is a narrowing conversion in java.

Conversion from type double to type long requires a nontrivial translation from a 64-bit floating-point value to the 64-bit integer representation. Depending on the actual run-time value, information may be lost.

e.g. following program will print 1 not 0

    long number = 499999999000000001L;
	double converted = (double) number;
	System.out.println( number - (long) converted);

Are you looking for the binary conversion?

double result = Double.longBitsToDouble(15552451L);

This will give you the double with the same bit pattern as the provided long.

Binary or hexadecimal literals will come in handy, here. Here are some examples.

double nan = Double.longBitsToDouble(0xfff0000000000001L);
double positiveInfinity = Double.longBitsToDouble(0x7ff0000000000000L);
double negativeInfinity = Double.longBitsToDouble(0xfff0000000000000L);

(See Double.longBitsToDouble(long))

You also can get the long back with

long bits = Double.doubleToRawLongBits(Double.NaN);

(See Double.doubleToRawLongBits(double))

Long i = 1000000;
String s = i + "";
Double d = Double.parseDouble(s);
Float f = Float.parseFloat(s);

This way we can convert Long type to Double or Float or Int without any problem because it's easy to convert string value to Double or Float or Int.

What do you mean by a long date type?

You can cast a long to a double:

double d = (double) 15552451L;

You can try something like this:

long x = somevalue;

double y = Double.longBitsToDouble(x);

I think it is good for you.

BigDecimal.valueOf([LONG_VALUE]).doubleValue()

How about this code? :D