You obviously know how to create arrays, so what problem are you having ?
Having said that though, rather than having four arrays to handle the different elements of a cache entry,
you should create a new class called CacheEntry which contains fields to represent each of the elements.
Your Cache class will then contain a one dimensional array of CacheEntry objects.
Have a go at implementing that and if you have any problems, come back with your code and we'll try and help.