Hash Codes

Equal objects must have equal hash codes. Objects are equal ⇒ Hashcodes are equal

• Remember what “equal” objects mean depending on how equals() is overriden
  • Oh yeah if equals() is overriden then you should almost always change hashCode() as well.
• A good hashCode tends to produce unequal hash codes for unequal objects
  • But at times unequal hashcodes may still reference
  • $\text{Unequal Objects}\to \text{Unequal Hash Codes}$
    • But two unequal objects may still have the same hash code (it just be like that sometimes)