How to get maximum value from the Collection (for example ArrayList)?
This question is almost a year old but I have found that if you make a custom comparator for objects you can use Collections.max for an array list of objects.
import java.util.Comparator;
public class compPopulation implements Comparator<Country> {
public int compare(Country a, Country b) {
if (a.getPopulation() > b.getPopulation())
return -1; // highest value first
if (a.getPopulation() == b.Population())
return 0;
return 1;
}
}
ArrayList<Country> X = new ArrayList<Country>();
// create some country objects and put in the list
Country ZZ = Collections.max(X, new compPopulation());
public int getMax(ArrayList list){
int max = Integer.MIN_VALUE;
for(int i=0; i<list.size(); i++){
if(list.get(i) > max){
max = list.get(i);
}
}
return max;
}
From my understanding, this is basically what Collections.max() does, though they use a comparator since lists are generic.
You can use the Collections API
to achieve what you want easily - read efficiently - enough
Javadoc for Collections.max
Collections.max(arrayList);
Returns the maximum element of the given collection, according to the natural ordering of its elements. All elements in the collection must implement the Comparable interface.