import java.util.Arrays;

public class StringFilter {
    public static void main(String[] args) {

        String[] arr = {"Alice", "Sue", "Janet", "Bea"};
        System.out.println(Arrays.toString(arr));


        String[] a1 = SFilter.filter(arr, new LenFilter(3));
        System.out.println(Arrays.toString(a1));


        String[] a2 = SFilter.filter(arr, new SFilter() {
            public boolean test(String s) {
                return (s.charAt(0) < 'D' && s.charAt(0) >='A');
            }
        });
        System.out.println(Arrays.toString(a2));


        String[] a3 = SFilter.filter(arr, s -> s.charAt(0) > 'H' && s.charAt(0) <= 'Z');
        System.out.println(Arrays.toString(a3));
    }
}
public interface SFilter {
    public boolean test(String s);
    public static String[] filter(String[] arr, SFilter filtr) {

        int count = 0;

        for(int i = 0; i < arr.length; i++) {
            if(filtr.test(arr[i]))
                count++;
        }
        String[] wyn =new String[count];
        count = 0;
        for(int i = 0; i < arr.length; i++) {
            if(filtr.test(arr[i])){
                wyn[count] = arr[i];
                count++;
            }
        }
        return wyn;
    }
}
public class LenFilter implements SFilter{

    private int minLen;

    public LenFilter(int minLen) {
        this.minLen = minLen;
    }
    @Override
    public boolean test(String s) {
        return s.length() > minLen;
    }

}