HashMaps and Null values?

Question

How do you pass in null values into a HashMap?
The following code snippet works with options filled in:

HashMap options = new HashMap         


        

Answer 1

It seems that you are trying to call a method with a Map parameter. So, to call with an empty person name the right approach should be

HashMap options = new HashMap();
options.put("name", null);  
Person person = sample.searchPerson(options);

Or you can do it like this

HashMap options = new HashMap();
Person person = sample.searchPerson(options);

Using

Person person = sample.searchPerson(null);

Could get you a null pointer exception. It all depends on the implementation of searchPerson() method.