剑指Offer-替换空格

/**
 * 题目描述 :
 *      请实现一个函数，将一个字符串中的每个空格替换成“%20”.
 *      例如，当字符串为We Are Happy.则经过替换之后的字符串为We%20Are%20Happy.
 * Created by guo.chen on 2018/9/9.
 */
public class SolutionⅡ {

    /**
     *把字符串转为 char 数组，遍历数组替换空格为一个标志，再转为字符串
     * 替换字符串中的标志
     * @param str
     * @return
     */
    public static String replaceSpace(String str) {
        char[] array = str.toCharArray();
        for(int i=0;i<array.length;i++){
            if(Character.isSpaceChar(array[i]))
            array[i] = ',';
        }
        str = new String(array);
        return str.replaceAll(",","%20");
    }

    public static void main(String[] args){
        String str = new String(" We are   Javaer  ");
        str = replaceSpace(str);
        System.out.println(str);
    }
}