Fish Touching🐟🎣

Java Idiom

Jun 7, 2023

# `equals()` And `hashCode()` Contracts

If two objects are equal according to the equals() method, then their hash codes must be equal as well.
If two objects have the same hash code, they may or may not be equal according to the equals() method.

# `equals`

@Override
public boolean equals(Object o) {
	if (this == o) return true;
	if (!(o instanceof Dog)) return false;
	Dog dog = (Dog) o;
	return getAge() == dog.getAge() && getName().equals(dog.getName()) && getBreed().equals(dog.getBreed());
    }

# `hashCode`

@Override
public int hashCode() {
	final int prime = 31;
	int result = 1;
	result = (prime * result) + columnIndex;
	result = (prime * result) + rowIndex;
	return result;
}

# Links