java - 将单词格式化为句子

Question

完成该方法，以便将单词格式化为单个逗号分隔值。最后一个单词应该用“and”而不是逗号分隔。应忽略空字符串值。传递给该方法的空数组或 null/nil 值应导致返回空字符串。

例子:

{"ninja", "samurai", "ronin"}) => "ninja, samurai and ronin"
{"ninja", "", "ronin"}) => "ninja and ronin"

代码

public static String formatWords(String[] words)
    {
        if (words == null || words.length == 0)
        {
            return "";
        }

        String str = "";

        for (int i = 0; i < words.length; i++)
        {
            if (words[i].equals(""))
                continue;
           if (i == words.length - 1)
               str += "and " + words[i];
           else
               str += words[i] + ", ";

        }

        return str;
    }

如何删除最后一个逗号？

Answer 1

一个简单的解决方案是按降序运行循环。我对您的代码进行了一些更改。希望，这有效

public static String formatWords(String[] words)
{
    Vector<String> v= new Vector<String>();
    if (words == null || words.length == 0)
        return "";

    for (int i = 0; i < words.length; i++)
        if (!words[i].equals("")) v.add(words[i]);

    String str="";
    for (int i = v.size()-1; i >= 0; i--)
    {
        if(str.equals("")){
            if(i>0)
                str = " and " + v.get(i);
            else
                str = v.get(i);
        }else{
            if(i==0)
                str = v.get(i) + str;
            else
                str = "," + v.get(i) + str;
        }
    }
    return str;
}

编辑:为解决评论中提到的@AJNeufeld 问题添加了 Vector 进行了更正