If you need to write your own equals methods, you should always override canEqual if you change equals and hashCode. NEW in Lombok 1.14.0: To put annotations on the other parameter of the equals (and, if relevant, canEqual) method, you can use onParam=@__({@AnnotationsHere}). Be careful though! This is an experimental feature. first off using == to check for equality of objects should never be done; replace it with. for compareTo you can simply return the compareTo of the strings. public int compareTo (Company b) { return this.cName.compareTo (b.cName); } It's a bit too strong to say that using == "should never be done". So the fastest way of comparing strings depends on: Whether your string objects are reused (like from a collection) or are always new (like from an input stream) Whether your strings differ at the start or the end of the string. Ignoring those facts, the majority of all programs will be fine with String.equals (). Solution: If we need key equality on different objects with the same value of instance variables, we need to implement equals () and hashCode () on the key. There are several methods to override equals () and hashCode () methods in Java. The following example uses static utility methods introduced with the Objects class in Java 7 that provides 3. You are printing the classes of worldX and block, but then comparing the former to bug (whatever that is). If they are the same class and getClass ().equals () returns false, one possibility is that there are multiple class loaders at play. Share. If a.equals(b) == true and a.equals(c) == true, then b.equals(c) must also return true. Persistence. The result of equals() must change only when the fields involved are changed. If we have two string objects, we use the equals() method to check if they are the same. In Java, we always use the equals() message to compare two objects – strings are just an example of that rule. For example, we used equals() to compare Color objects earlier in the quarter. The == operator is similar but is used to compare primitives such To compare Strings for equality, don't use ==. The == operator checks to see if two objects are exactly the same object. Two strings may be different objects, but have the same value (have exactly the same characters in them). Use the .equals() method to compare strings for equality. XUApT.

how to use equals method in java