Java HashMap get works but containsKey does not

Question

I am trying to locate a key in a HashMap. I can print the selected key by using \'get\' but when I use \'containsKey\' in an if statement, it is not found.

I KNOW

Answer 1

containsKey uses the method equals to compare the param with the entries in the key set. So the Location class needs to have a equals method that is good. The default equals method in java.lang.Object only returns true when both objects are the same object. In this case you probably have 2 different instances that needs to be compared and need a custom equals method.