java - 验证标签是否在另一个 Java 正则表达式中

Question

我必须验证 <tagN> (其中 N 是数字)位于标签 <p></p> 内。万一它不在<p>里面，我必须补充一下。否则就可以了。我有所有这些情况，我尝试了一段时间，但找不到覆盖所有情况的模式:

import java.util.regex.*;


public class Main {

    static String case1 = "<p><tag1></p>";                              // Output: Group 1: <p>. Group 2: <tag1>. Group 3: </p>
    static String case2 = "<tag1>";                                     // Output: Group 1: null. Group 2: <tag1>. Group 3: null
    static String case3 = "<p>     <tag1>        </p>";                 // Output: Group 1: <p>. Group 2: <tag1>. Group 3: </p>
    static String case4 = "<><tag1></p>";                               // NO OK. Output: Group 1: null. Group 2: <tag1>. Group 3: </p>
    static String case5 = "<p><tag1><tag2></p>";                        // Output: Group 1: <p>. Group 2: <tag1><tag2>. Group 3: </p>
    static String case6 = "<p>   <tag1>  <tag2>   </p>";                // Output: Group 1: <p>. Group 2: <tag1><tag2>. Group 3: </p>
    static String case7 = "<p>   <tag1>\n\n<tag2>   </p>";              // Output: Group 1: <p>. Group 2: <tag1><tag2>. Group 3: </p>
    static String case8 = "<p>\n\n   <tag1>\n\n<tag2>   \n</p>";        // Output: Group 1: <p>. Group 2: <tag1><tag2>. Group 3: </p>
    static String case9 = "   <tag1>  <tag2>   ";                       // Output: Group 1: null. Group 2: <tag1><tag2>. Group 3: null
    static String case10 = "  <tag1>\n\n<tag2>   ";                     // Output: Group 1: null. Group 2: <tag1><tag2>. Group 3: null
    static String case11 = "\n\n   <tag1>\n\n<tag2>   \n";              // Output: Group 1: null. Group 2: <tag1><tag2>. Group 3: null

    public static void main(String[] args) {
        //String patternString = "(<p>\\s*)*([<tag\\d+>\\s*]+)(\\s*</p>)*"; // Works only for cases 2, 9, 10 and 11
        //String patternString = "(<p>\\s*)*(<tag\\d+>+)(\\s*</p>)*"; // Works only for cases 1, 2, 3, 4
        Pattern pattern = Pattern.compile(patternString);
        Matcher matcher = pattern.matcher(case5);

        while (matcher.find()) {
            System.out.println("Group 0: " + matcher.group(0));
            System.out.println("Group 1: " + matcher.group(1));
            System.out.println("Group 2: " + matcher.group(2));
            System.out.println("Group 3: " + matcher.group(3));

            // The idea here is add tag <p> when group 1 is null and tag </p> when group 3 is null
        }

    }
}

基本上，我尝试分成 3 组:

• 第 1 组:标签 (<p>\\s*)* // \\s is for whitespaces/tab/newlines in case it finds 0 or more

• 第 2 组:尝试重复 tag1、tag2 等，这就是包含在 []+ 中的原因但似乎不行

• 第 3 组:标签 (\\s*</p>)* // \\s is for whitespaces/tab/newlines in case it finds 0 or more

有什么想法吗？谢谢

Answer 1

最后，我不得不替换 <tag1>通过 ~tag1~第一个表达式就OK了。

String patternString = "(<p>\\s*)*([~tag\\d+~\\s*]+)(\\s*</p>)*";

通过这两个更改，我得到了预期的结果。谢谢