Question

How do I find out, how many values my enum has in this example:

public class Analyser<C extends Enum<C>>{
  private long[] dist;
  public Analyser() {
    super();
    dist = new long [C.getEnumConstants().length];
  }
}

The last line does not work.

Answer 1

You need to pass in the class literal of the enum:

public Analyser(Class<C> enumType) {
    super();
    dist = new long [enumType.getEnumConstants().length];
}

...

Analyser<MyEnum> analyser = new Analyser(MyEnum.class);

This is because C has no meaning at runtime due to type erasure.