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我正在尝试用 Java 编写一个 madlibs 程序。有一种方法采用模板字符串、该字符串中所有占位符的 ArrayList 以及将替换这些模板的所有用户输入的 ArrayList 作为参数。

该方法如下所示：

private String replacePlaceHolder(String template, ArrayList<String> placeholders, ArrayList<String> replacements){
        for (int i = 0; i < placeholders.size(); i++){
            template = template.replace(placeholders.get(i), replacements.get(i));
        }
        return template;
    }

问题是，该方法是用替换替换所有出现的给定模板，例如“[形容词]”，而不仅仅是第一个。我尝试template = template.replaceFirst(placeholders.get(i), replacements.get(i))改用，但它用所有用户输入替换了第一个占位符，并忽略了其余部分。

这是我使用的模板：

Computer programming, also known as [-ing Verb], is a
process that leads from a [Adjective] problem 
to an executable [Noun]. 
Programming often involves [-ing Verb], 
[-ing Verb], and [-ing Verb], and can be learned
by anyone!
Source code is written in a programming language, 
such as [Animal]code, or Java.
The first ever programmer was [Name of Celebrity], 
who invented [Plural Noun] in the year [Year]. 
Since then, programming has become a 
[Adjective] practice all across the world.

我知道占位符的 ArrayList 与模板中的占位符匹配，并且该 ArrayList 与用户输入的 ArrayList 长度相同。

我应该做些什么不同的事情？

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1 回答 1

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replaceFirst是正确的答案，但参数是正则表达式，所以你需要引用搜索文本，特别是因为它使用[]，这是字符类的特殊正则表达式。

要引用这些值，请使用Pattern.quote(String s)第一个参数和Matcher.quoteReplacement(String s)第二个参数。

private static String replacePlaceHolder(String template, List<String> placeholders, List<String> replacements) {
    for (int i = 0; i < placeholders.size(); i++){
        template = template.replaceFirst(Pattern.quote(placeholders.get(i)),
                                         Matcher.quoteReplacement(replacements.get(i)));
    }
    return template;
}

这是一个Minimal, Reproducible Example，您应该在问题中提供一些内容：

String template = "Computer programming, also known as [-ing Verb], is a\n" +
                  "process that leads from a [Adjective] problem\n" +
                  "to an executable [Noun].\n" +
                  "Programming often involves [-ing Verb],\n" +
                  "[-ing Verb], and [-ing Verb], and can be learned\n" +
                  "by anyone!\n" +
                  "Source code is written in a programming language,\n" +
                  "such as [Animal]code, or Java.\n" +
                  "The first ever programmer was [Name of Celebrity],\n" +
                  "who invented [Plural Noun] in the year [Year].\n" +
                  "Since then, programming has become a\n" +
                  "[Adjective] practice all across the world.";
List<String> placeholders = Arrays.asList(
        "[-ing Verb]", "[Adjective]", "[Noun]",
        "[-ing Verb]", "[-ing Verb]", "[-ing Verb]",
        "[Animal]", "[Name of Celebrity]", "[Plural Noun]",
        "[Year]", "[Adjective]" );
List<String> replacements = Arrays.asList(
        "AA", "BB", "CC",
        "DD", "EE", "FF",
        "GG", "HH", "II",
        "JJ", "KK" );
String result = replacePlaceHolder(template, placeholders, replacements);
System.out.println(result);

输出

Computer programming, also known as AA, is a
process that leads from a BB problem
to an executable CC.
Programming often involves DD,
EE, and FF, and can be learned
by anyone!
Source code is written in a programming language,
such as GGcode, or Java.
The first ever programmer was HH,
who invented II in the year JJ.
Since then, programming has become a
KK practice all across the world.
于 2019-11-28T20:20:39.843 回答