I've got one class, that I sort it already by one attribute. Now I need to make another thing, that I need to create another way to sort my data. How can I make it, so I can choose between the two methods. The only command I know is Collections.sort that will pick up the method compareTo from the class I want to compare its data.
Is it even possible?
What you need to do is implement a custom Comparator
. And then use:
Collections.sort(yourList, new CustomComparator<YourClass>());
Specifically, you could write: (This will create an Anonymous class that implements Comparator
.)
Collections.sort(yourList, new Comparator<YourClass>(){
public int compare(YourClass one, YourClass two) {
// compare using whichever properties of ListType you need
}
});
You could build these into your class if you like:
class YourClass {
static Comparator<YourClass> getAttribute1Comparator() {
return new Comparator<YourClass>() {
// compare using attribute 1
};
}
static Comparator<YourClass> getAttribute2Comparator() {
return new Comparator<YourClass>() {
// compare using attribute 2
};
}
}
It could be used like so:
Collections.sort(yourList, YourClass.getAttribute2Comparator());