How to do a Comparator with two properties ?

[majid nakit]

Hi,

I have a class :

public class Person {
    private String firstName;
    private String lastName;
    private String gender;
    private String birthDate;  

    // constructors, getters,

I would like to create a comparator :by Gender (Female before Male), then Last Name ascending

public class GenderLastNameAscComparator implements Comparator<Person> {

Please your help is appreciated.
thanks

[Joanne Neal]

majid nakit wrote:I would like to create a comparator :by Gender (Female before Male), then Last Name ascending

okay. So what problem are you having ? What have you tried ?

[majid nakit]

Hi,
I did this :

[Paul Clapham]

Okay. Then what results did you get, and what results did you expect, and how do those differ?

[Campbell Ritchie]

Why have you got gender as a String rather than an enum member or similar?

[Jesper de Jong]

What does the rest of your program look like? Maybe you're not calling the sorting code correctly.

[Winston Gutkowski]

majid nakit wrote:I did this:
...
This is what I got:...

Well, I don't see anything wrong with your compare() method, so Jesper's advice might be worth looking into.

Just FYI: You can reduce your code a little with the ternary operator, viz:
int ret = a.getGender().compareTo(b.getGender());
return ret == 0 ? a.getLastname().compareTo(b.getLastname()) : ret;
but it's just a style thing; what you have is perfectly fine.

Winston