Compare Java hashing functions between JVM invocations. NOTE: This example will only run on Java 7.

Hash.java

public class Hash {
  public static void main(String[] args) {
    String str = "Java Programming Language";
    System.out.println(str + " hashCode(): " 
        + str.hashCode() 
        + " new Java 7 hashCode used by collections: " 
        + sun.misc.Hashing.stringHash32(str));
  }
}