Question

I have a custom object like this :

 Linkedlist<ClassInfo> classes = new LinkedList<ClassInfo>();

Within that, there are accessors for a teacher’s name, the class name, the room number, etc. These are all Strings. I have run into a situation where the data in that LinkedList needs to displayed by different parameters (i.e. teacher name, class name, the room number, etc.).

Can anyone supply a quick implementation of how to do this? If I use the Compartor interface, how would I be able tell it which String field to sort the list by? My research also lead me to the Collator, and I was wondering if this would be of use.

Appreciate any help.

Answer 1

Write a different Comparator implementation for each field:

Comparator<ClassInfo> CLASS_NAME_COMPARATOR = new Comparator<ClassInfo>() {
  public int compare(ClassInfo class1, ClassInfo class2) {
    return class1.getClassName().compareTo(class2.getClassName());
  }
};
... // implementations for other fields

…and then sort by whichever comparator is appropriate:

Collections.sort(classes, CLASS_NAME_COMPARATOR);