I am trying to create a method that counts how many collision occur in a hash table. Would I check the entire table to see how many buckets have more than 1 element?
Draft:
public int getCollisions() { int counter = 0; for (int i = 0; i < buckets.length; i++) { if (buckets.length > 1) { counter += i; } } return counter; } I would probably use this -
public long getCollisions() { long counter = 0; for (int i = 0; i < buckets.length; i++) { if (buckets[i].length > 1) { counter += buckets[i].length; // 2 (or more) items collided in this bucket. } } return counter; } 
buckets[i].length, shouldn't length be a default method?You are adding the index of the bucket, not the number of collisions to your counter. Try this instead:
public int getCollisions() { int counter = 0; for (int i = 0; i < buckets.length; i++) { if (buckets[i].length > 1) { counter += buckets[i].length-1; } } return counter; } Here I am assuming that if there are n objects in a bucket (where n>1), there are n-1 collisions in that bucket. If I am incorrect in assuming that, then just remove the -1 and it should work fine.
if (bucket.length > 1) { counter += bucket.length; }