Hashcode functions are built into Java standard classes. Check out the JavaDocs for java.lang.Object - the hashcode() method for example discussion.
posted 5 years ago
Welcome to the Ranch Find copies of Effective Java by Bloch, or Thinking in Java by Eckel, which used to be available free on the web (3/e), or Google for Niklaus Wirth's Algorithms book. You should find details of hashing algorithms in those.