Overriding the java equals() method - not working?

Question

I ran into an interesting (and very frustrating) issue with the equals() method today which caused what I thought to be a well tested class to crash and cause a

Answer 1

Another fast solution that saves boilerplate code is Lombok EqualsAndHashCode annotation. It is easy, elegant and customizable. And does not depends on the IDE. For example;

import lombok.EqualsAndHashCode;

@EqualsAndHashCode(of={"errorNumber","messageCode"}) // Will only use this fields to generate equals.
public class ErrorMessage{

    private long        errorNumber;
    private int         numberOfParameters;
    private Level       loggingLevel;
    private String      messageCode;

See the options avaliable to customize which fields to use in the equals. Lombok is avalaible in maven. Just add it with provided scope:

    org.projectlombok
    lombok
    1.14.8
    provided