Is there something like bytes(byte...b):byte[]?

i am looking fo开发者_StackOverflow中文版r a simple method were i can pass in some bytes, as varargs, and get a byte[] returned, like:

static byte[] byteArray(byte ...bytes){ return bytes;}

What i found so far...

java.lang.Byte doesn't have it

java.util.Arrays doesn't have it

com.google.common.primitives.Bytes.toArray(..) want a Collection

sample use case: assertThat(actualArray,is(byteArray(1,2,3,4,5)));

There is no function for that because

new byte[]{1,2,3,4,5}

is also quite short.

Edit: Please note that any helper method like this

static byte[] toBytes(byte ... bytes)
{
   return bytes;
}

has the same problem as new byte{...}: All arguments must be real bytes and not propagated to int. So arguments like 0xca must be casted to bytein both cases:

byte ba1[] = new byte[]{ (byte)0xca };
byte ba2[] = toBytes( (byte)0xca );

If you want easier input then you must write a custom method which allocates a byte array and do the coping and casting by hand.

If you're assigning the bytes to a variable or field of type byte[], you can write this even more compactly than new byte[]{1, 2, 3, 4}:

byte[] bytes = {1, 2, 3, 4};

Also, the problem with 0xca, 0xfe, 0xba, 0xbe is that all of those values are actually outside the legal range for a Java byte, since byte in Java is signed by default.

Perhaps you want a method that takes an argument of type long... and returns a byte[], using UnsignedBytes.checkedCast or UnsignedBytes.saturatedCast to convert each value.