Java中没有API来获取命名捕获组的名称。我认为这是一个缺少的功能。
一种简单的方法是从模式中选择候选的命名捕获组，然后尝试 从match中
访问命名组。换句话说，在插入匹配整个模式的字符串之前，您不知道命名捕获组的确切名称。
该
Pattern捕捉名为捕获组的名称是
(?<([a-zA-Z][a-zA-Z0-9]*)>（根据派生
Pattern类的文档）。
（最困难的方法是为正则表达式实现解析器并获取捕获组的名称）。
一个示例实现：
import java.util.Scanner;import java.util.Set;import java.util.TreeSet;import java.util.Iterator;import java.util.regex.Pattern;import java.util.regex.Matcher;import java.util.regex.MatchResult;class RegexTester { public static void main(String args[]) { Scanner scanner = new Scanner(System.in); String regex = scanner.nextLine(); StringBuilder input = new StringBuilder(); while (scanner.hasNextLine()) { input.append(scanner.nextLine()).append('n'); } Set<String> namedGroups = getNamedGroupCandidates(regex); Pattern p = Pattern.compile(regex); Matcher m = p.matcher(input); int groupCount = m.groupCount(); int matchCount = 0; if (m.find()) { // Remove invalid groups Iterator<String> i = namedGroups.iterator(); while (i.hasNext()) { try { m.group(i.next()); } catch (IllegalArgumentException e) { i.remove(); } } matchCount += 1; System.out.println("Match " + matchCount + ":"); System.out.println("=" + m.group() + "="); System.out.println(); printMatches(m, namedGroups); while (m.find()) { matchCount += 1; System.out.println("Match " + matchCount + ":"); System.out.println("=" + m.group() + "="); System.out.println(); printMatches(m, namedGroups); } } } private static void printMatches(Matcher matcher, Set<String> namedGroups) { for (String name: namedGroups) { String matchedString = matcher.group(name); if (matchedString != null) { System.out.println(name + "=" + matchedString + "="); } else { System.out.println(name + "_"); } } System.out.println(); for (int i = 1; i < matcher.groupCount(); i++) { String matchedString = matcher.group(i); if (matchedString != null) { System.out.println(i + "=" + matchedString + "="); } else { System.out.println(i + "_"); } } System.out.println(); } private static Set<String> getNamedGroupCandidates(String regex) { Set<String> namedGroups = new TreeSet<String>(); Matcher m = Pattern.compile("\(\?<([a-zA-Z][a-zA-Z0-9]*)>").matcher(regex); while (m.find()) { namedGroups.add(m.group(1)); } return namedGroups; } }}但是，此实现有一个警告。目前，它不适用于regex
Pattern.COMMENTS模式。
