HashTable has these tunable parameters:
Capacity (usually a prime number), initialCapacity; if this is not set large enough, collisions will result, causing hashing to stop and linear list processing to be executed afterwards.
Load factor (0.0-1.0), loadFactor, which is a percentage of capacity beyond which the table will expand. HashTable calls hashCode(). These classes have pre-defined hashCode() methods:
Color, Font, Point
Boolean, Byte, Character, Double, Float, Integer, Long, Short, String
BitSet, Date, GregorianCalendar, Locale, SimpleTimeZone. Note that String.hashCode() does not always sample all the characters, depending on the length:
Length from 1 to 15: all n Length from 16 to 23: every other character
Length from 24 to 31: every third character