How to compare two java objects [duplicate]

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You need to provide your own implementation of equals() in MyClass.

@Override
public boolean equals(Object other) {
    if (!(other instanceof MyClass)) {
        return false;
    }

    MyClass that = (MyClass) other;

    // Custom equality check here.
    return this.field1.equals(that.field1)
        && this.field2.equals(that.field2);
}

You should also override hashCode() if there’s any chance of your objects being used in a hash table. A reasonable implementation would be to combine the hash codes of the object’s fields with something like:

@Override
public int hashCode() {
    int hashCode = 1;

    hashCode = hashCode * 37 + this.field1.hashCode();
    hashCode = hashCode * 37 + this.field2.hashCode();

    return hashCode;
}

See this question for more details on implementing a hash function.

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