Java Bitset类与Byte数组的比较-Byte数组优于Bitset类的优点

Question

The Java Bitset class is dynamic and its size changes accordinly with the bits ON in it. But Byte array can hold specific number of bits and it is easy to be used with the SQL server for copying and retrieving data from database. Is this true?

Can Bitset class be used for very large bit calculations (logical operations OR, AND). Or byte array has the edge over it as with byte array we can deal with specific parts of the bits and modify them accordingly?

Answer 1

If there is a standard class that provides the functionality you need, you should use that class in preference to writing your own code. Because the writers of the library are probably (no offence meant) better programmers than you and the code has already been tested and debugged. Only if you have concrete facts to indicate that the standard class has insufficient performance should you consider writing your own... and even then your efforst are unliklely to be successful.

Answer 2

byte[] is a magnitude larger than a bitset for the same amount of data (ie. 8 times as much space is allocated), because a byte = 8 bits. What also works is using an int/long to represent a bitset, which is what I used to represent large enum sets in a database. Why would you shy away from a BitSet if it is made especially for the purpose of storing bits...