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--- java:constructor_basics [2020/09/12 05:03] – [toString()] mithat
+++ java:initializing_classes_and_constructors [2020/09/16 18:15] (current) – [equals(other)] mithat
@@ Line 145: / Line 145: @@
 Writing a ''toString()'' instance method is especially important when your class is more complicated than the simple class we've been using here. To understand the magic by which this works, you need to have an understanding of inheritance in Java. But that shouldn't stop you from doing this now.
+===== equals(other) =====
+Another method that you can define and is a good habit to get into defining is ''equals''. A very basic definition of `equals` is created automatically, but in almost all cases, you will want to change this functionality. An example of an ''equals'' method for the ''ClickerCounter'' class might look like:
+<code java>
+public boolean equals(ClickerCounter other) {
+    return (this.count == other.count &&
+            this.maxCount == other.maxCount);
+}
+</code>
+It's up to you to decide what "equals" means. In many cases, "equals" means that two objects of the same class have the same state. So, in the above definition, for two counter to be equal, both the count and the maxCount must be the same. Now to use this method, assuming both of the variables below refer to valid ''ClickerCounters'':
+<code java>
+if (myCounter.equals(yourCounter) {
+    System.out.println("Our counters are the same.");
+} else {
+    System.out.println("Your counter and mine are not the same.");
+}
+</code>
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