21 In .NET, a byte is basically a number from 0 to 255 (the numbers that can be represented by eight bits). So, a byte array is just an array of the numbers 0 - 255. At a lower level, an array is a contiguous block of memory, and a byte array is just a representation of that memory in 8-bit chunks.
I have to store some constant values (UUIDs) in byte array form in java, and I'm wondering what the best way to initialize those static arrays would be. This is how I'm currently doing it, but I feel
Endianness and byte order When a value larger than byte is stored or serialized into multiple bytes, the choice of the order in which the component bytes are stored is called byte order, or endian, or endianness. Historically, there have been three byte orders in use: "big-endian", "little-endian", and "PDP-endian" or "middle-endian".
How to convert byte[] to Byte[] and also Byte[] to byte[], in the case of not using any 3rd party library? Is there a way to do it fast just using the standard library?
A byte is 8 bits (binary data). A byte array is an array of bytes (tautology FTW!). You could use a byte array to store a collection of binary data, for example, the contents of a file. The downside to this is that the entire file contents must be loaded into memory. For large amounts of binary data, it would be better to use a streaming data type if your language supports it.
byte z = (byte)(x + y); // this works What I am wondering is why? Is it architectural? Philosophical? We have: int + int = int long + long = long float + float = float double + double = double So why not: byte + byte = byte short + short = short? A bit of background: I am performing a long list of calculations on "small numbers" (i.e. < 8) and storing the intermediate results in a large array ...
Because gustafc's answer has a very important point: String (byte []) constructor uses the System default encoding to convert the byte array into String characters. One should not assume that a 0x63 byte value is mapped to the letter 'c'. For example, in UTF-16 the letter 'c' is represented by 2 encoding bytes, not one.
How do I convert a byte[] to a string? Every time I attempt it, I get System.Byte[] instead of the value. Also, how do I get the value in Hex instead of a decimal?
On a binary computer a byte must therefore be composed of six bits; on a decimal computer we have two digits per byte.* - The Art of Computer Programming, Volume 1, written by Donald Knuth. And... * Since 1975 or so, the word "byte" has come to mean a sequence of precisely eight binary digits, capable of representing the numbers 0 to 255.
The byte is the smallest addressable unit for a CPU. If you want to set/clear single bits, you first need to fetch the corresponding byte from memory, mess with the bits and then write the byte back to memory.
