how to sort

[Feng]

what is the way to sort alphabetically strings from an array?

(for example lets say we have the strings "Apple", "Key" and "Zebra" in an array of 5 elements.)

[hardwired]

String implements the Comparable interface so we can use the compareTo method for sorting. See first paragraph and "Classes Implementing Comparable" table at Object Ordering for bird's–eye view.

public class Sorting {
    public static void main(String[] args) {
        String[] array = { "five", "Apple", "Zebra", "Key", "elements" };
        sort(array);
        print(array);
        sortIgnoreCase(array);
        print(array);
    }

    private static void sort(String[] strs) {
        for(int j = 0; j < strs.length; j++) {
            String minValue = strs[j];
            int minIndex = j;
            for(int k = j+1; k < strs.length; k++) {
                if(strs[k].compareTo(minValue) < 1) {
                    minValue = strs[k];
                    minIndex = k;
                }
            }
            if(minIndex != j) {
                // found a lower value - swap elements
                String temp = strs[j];
                strs[j] = minValue;
                strs[minIndex] = temp;
            }
        }
    }
    
    private static void sortIgnoreCase(String[] strs) {
        for(int j = 0; j < strs.length; j++) {
            String minValue = strs[j].toLowerCase();
            int minIndex = j;
            for(int k = j+1; k < strs.length; k++) {
                if(strs[k].toLowerCase().compareTo(minValue) < 1) {
                    minValue = strs[k].toLowerCase();
                    minIndex = k;
                }
            }
            if(minIndex != j) {
                // found a lower value - swap elements
                String temp = strs[j];
                strs[j] = minValue;
                strs[minIndex] = temp;
            }
        }
    }

    private static void print(String[] strs) {
        for(int j = 0; j < strs.length; j++) {
            System.out.print(strs[j]);
            if(j < strs.length-1)
                System.out.print(", ");
        }
        System.out.println();
    }
}