String类中的Public int compareTo(String s)方法

字符串对象可以使用string类中的compareTo(String s)方法按字典序与参数s指定的字符串比较大小。如果当前字符串与s相同，该方法返回值零，如果当前字符串对象大于s该方法返回值正值，如果小于s，该方法返回值负值。

package Test02;

public class Test02 {
    public static void main(String[] args) {
        String[] a = {"melon","apple","pear","banana"};
        String[] b = {"西瓜","苹果","梨","香蕉"};
        System.out.println("按字典序排序数组a:");
        SortString.sort(a);
        for (int i = 0; i < a.length; i++) {
            System.out.print(" "+a[i]);

        }
        System.out.println("n按字典序排序数组b:");
        SortString.sort(b);
        for (int i = 0; i < b.length; i++) {
            System.out.print(" "+b[i]);
        }
    }
}
class SortString {
    public static void sort(String a[]){
        int count = 0;
        for (int i = 0; i < a.length-1; i++) {
            for (int j = i+1; j < a.length; j++) {
                if (a[j].compareTo(a[i])<0){
                    String temp = a[i];
                    a[i] = a[j];
                    a[j] = temp;
                }
            }
        }
    }

}

按字典序排序数组a:
 apple banana melon pear
按字典序排序数组b:
 梨 苹果 西瓜 香蕉