Question

Make the Measurable interface from Chapter 10 into a generic class. Provide a static method that returns the largest element of an ArrayList, provided that the elements are instances of Measurable. Be sure to return a value of type T.

Measurable interface:

public interface Measurable {

double getMeasure();

}

Using JAVA please

Answer 1

import java.util.ArrayList;
import java.util.Arrays;

public class LargestMeasurable {

    public static <T extends Measurable> T max(ArrayList<T> list) {
        if (list == null || list.isEmpty())
            return null;
        T largest = list.get(0);
        for (int i = 0; i < list.size(); i++) {
            if (list.get(i).getMeasure() > largest.getMeasure()) {
                largest = list.get(i);
            }
        }
        return largest;
    }

    public static void main(String[] args) {
        Measurable[] arr = {
                new Measurable() {
                    @Override
                    public double getMeasure() {
                        return 10;
                    }
                },
                new Measurable() {
                    @Override
                    public double getMeasure() {
                        return 2;
                    }
                },
                new Measurable() {
                    @Override
                    public double getMeasure() {
                        return 7;
                    }
                },
                new Measurable() {
                    @Override
                    public double getMeasure() {
                        return 9;
                    }
                },
        };
        System.out.println(max(new ArrayList<>(Arrays.asList(arr))).getMeasure());
    }
}