Select an object on the basis of its minimum attribute value from list in Java

Question

I have a class

public class LocationDistances {
    String locs;
    double distances;

}

and an ArrayList composed of LocationDistances objects in another class

ArrayList<LocationDistances> locsDis = new ArrayList(Arrays.asList(
    new LocatoinDistances("abc",23.234556),
    new LocatoinDistances("xyz",3.3444566),
    . . . 
    . . .
    . . .

));

How to select LocationDistances.locs from Array list on the basis of minimum value of LocationDistances.distance from the locsDis arrayList?

Answer 1

If you are using Java 8 (You should :)) :

locsDis.stream().min((first, second) -> Double.compare(first.distance, second.distance)).get();

Edit: Decided to make this post a bit more comprehensive to help those of us that are still confined to Java < 8 but can use the awesome library guava :)

Java 6 & 7 With guava (Google util library):

Ordering<LocationDistances> ordering = new Ordering<LocationDistances>() {
    @Override
    public int compare(LocationDistances left, LocationDistances right) {
        return Double.compare(left.distance, right.distance);
    }
};
return ordering.max(list);

Answer 2

Something like this would work if there are no duplicate distances.

LocationDistances min=null;
for(LocationDistances x:locsDis){
    min=(min==null||x.distances<min.distances)?x:min;
}
String minimumDistance=min.locs;

if there are duplicate distances use something like this

ArrayList<LocationDistances> min=new  ArrayList<LocationDistances>();

for(LocationDistances x:locsDis){
    if(min.size()==0||x.distances==min.get(0).distances)
           min.add(x);
    else if(x.distances<min.get(0).distances){
           min.clear();
           min.add(x);
    }               
}