Java字符串和单词的反转

import java.util.Scanner;

/**
 * Created by cuboo on 2016/10/13.
 */
public class test {
    private static Scanner scanner;
    public static void main(String agrs[]){
        scanner = new Scanner(System.in);
        String line = scanner.nextLine();
        word_reverse(line);

    }
    //字符反转
    public static void char_reverse(String line){

        char[] chars = new char[line.length()];
        for (int i = line.length()-1,j = 0; i >= 0; i--,j++) {
            chars[j] = line.charAt(i);
            System.out.println(chars[j]);
        }
        line = String.copyValueOf(chars);
        System.out.println(line);
        //方法2 更简单：
        StringBuffer sb = new StringBuffer();
        //方法3 更简单 更快
        StringBuilder sb1 = new StringBuilder();
        sb.append(line);

        sb.append(line);
        System.out.println(sb.reverse());
        System.out.println(sb1.reverse());
    }
    //单词反转
    public static void word_reverse(String line){
        String[] str = line.split(" ");
        StringBuilder str1 = new StringBuilder();
        
        for (int i = str.length-1; i >= 0; i--) {
            str1.append(str[i]);
            if (i>0){
                str1.append(" ");
            }
        }
        System.out.println(str1);

    }
}