How do you come up with a hash function for a generic object? There is the constraint that two objects need to have the same hash value if they are “equal” as defined by the user. How does Java accomplish this?
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How do you come up with a hash function for a generic object? There is the constraint that two objects need to have the same hash value if they are “equal” as defined by the user. How does Java accomplish this?
Hashing of an object is established by overriding
hashCode()method, which the developer can override.Java uses prime numbers in the default hashcode calculation.
If the
equals()andhashCode()method aren’t implemented, the JVM will generate hashcode implicitly for the object (for Serializable classes, aserialVersionUIDis generated).