Interface HashingStrategy<T>

public interface HashingStrategy<T>
Abstraction for hash code generation and equality comparison.

  • Field Details

  • Method Details

    • hashCode

      int hashCode(T obj)
      Generate a hash code for obj.

      This method must obey the same relationship that Object.hashCode() has with Object.equals(Object):

      • Calling this method multiple times with the same obj should return the same result
      • If equals(Object, Object) with parameters a and b returns true then the return value for this method for parameters a and b must return the same result
      • If equals(Object, Object) with parameters a and b returns false then the return value for this method for parameters a and b does not have to return different results results. However this property is desirable.
      • if obj is null then this method return 0

    • equals

      boolean equals(T a, T b)
      Returns true if the arguments are equal to each other and false otherwise. This method has the following restrictions:
      • reflexive - equals(a, a) should return true
      • symmetric - equals(a, b) returns true if equals(b, a) returns true
      • transitive - if equals(a, b) returns true and equals(a, c) returns true then equals(b, c) should also return true
      • consistent - equals(a, b) should return the same result when called multiple times assuming a and b remain unchanged relative to the comparison criteria
      • if a and b are both null then this method returns true
      • if a is null and b is non-null, or a is non-null and b is null then this method returns false