Java替换()问题

Question

我应该输入一个字符串，并将所有and、to、you和for子字符串替换为&、2、U和4。

当我输入字符串"and , and,and , to , to,to , you ,you , you, for ,for , for,a , a,e , e,i , i,o , o,u , u"时，它只在打印它时输出and。

public void simplify()
{
    System.out.println("Enter a string to simplify: ");
    String rope = in.next();
    System.out.println(simplifier(rope));
}
public String simplifier(String rope)
{

    rope = rope.replace(" and "," & ");
    rope = rope.replace(" and"," &");
    rope = rope.replace("and ","& ");
    rope = rope.replace(" to "," 2 ");
    rope = rope.replace(" to"," 2");
    rope = rope.replace("to ","2 ");
    rope = rope.replace(" you "," U ");
    rope = rope.replace("you ","U ");
    rope = rope.replace(" you"," U");
    rope = rope.replace(" for "," 4 ");
    rope = rope.replace("for ","4 ");
    rope = rope.replace(" for"," 4");
    rope = rope.replace("a ","");
    rope = rope.replace(" a","");
    rope = rope.replace("e ","");
    rope = rope.replace(" e","");
    rope = rope.replace("i ","");
    rope = rope.replace(" i","");
    rope = rope.replace(" o","");
    rope = rope.replace("o ","");
    rope = rope.replace("u ","");
    rope = rope.replace(" u","");
    System.out.print(rope);
    return rope;
}

输出：and and

它似乎在第一个空格之后切断了返回的字符串。

我不知道这是怎么回事，也不知道它为什么不能正常工作。我做错了什么？

Answer 1

下面是我如何简化您的代码并得到正确的结果：

    String rope = "and , and,and , to , to,to , you ,you , you, for ,for , for,a , a,e , e,i , i,o , o,u , u";

   // rope = rope.replaceAll(" ", "");
    rope = rope.replaceAll("and", "&");
    rope = rope.replaceAll("to", "2");
    rope = rope.replaceAll("you", "U");
    rope = rope.replaceAll("for", "4");
    rope = rope.replaceAll("a", "");
    rope = rope.replaceAll("e", "");
    rope = rope.replaceAll("i", "");
    rope = rope.replaceAll("o", "");
    rope = rope.replaceAll("u", "");
    System.out.println(rope);

Answer 2

将第一个rope = rope.replace(" and "," & ");替换为rope = rope.replace("and "," & ");

现在该起作用了。问题是，第一个“和”您试图替换的是and，而不是and，这就是为什么会留下而没有被替换。

还删除simplifier的第二行，即System.out.print(rope);。这是重复的，因为您已经在调用方法中打印结果。

更新:我明白你在做什么了。试试这个：

对于要替换的每个单词，只替换一次。因此，对于and，请做：

rope.replace("and", "&");

对于to，请执行以下操作：

rope.replace("to", "2");

不在单词之间添加任何空格，这是不必要的。执行replace()一次将取代所有的出现的那个单词。