Chinese Date Format (YYYY年MM月DD日) Regex for Java
/^((?:19|20)[0-9]{2})年(0?[1-9]|1[0-2])月(0?[1-9]|[12][0-9]|3[01])日$/What this pattern does
This page provides a well-structured, multi-part regular expression for matching chinese date format (yyyy年mm月dd日), ported and verified for Java. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your Java project — whether you're validating in a Spring Boot controller, a Jakarta EE service, or a standalone utility class.
Java Implementation
// Chinese Date Format (YYYY年MM月DD日)
// ReDoS-safe | RegexVault — Localization > Date Formats
import java.util.regex.Pattern;
public class ChineseDateFormatYyyymmddValidator {
private static final Pattern PATTERN =
Pattern.compile("^((?:19|20)[0-9]{2})年(0?[1-9]|1[0-2])月(0?[1-9]|[12][0-9]|3[01])日$");
public static boolean validate(String input) {
return PATTERN.matcher(input).matches();
}
// Example
public static void main(String[] args) {
System.out.println(validate("2024年1月15日")); // true
}
}Test Cases
Matches (Valid) | Rejects (Invalid) |
|---|---|
2024年1月15日 | 2024年13月15日 |
2024年12月31日 | 2024年01月32日 |
1999年06月01日 | 2024/01/15 |
When to use this pattern
This pattern is drawn from the Localization > Date Formats category and carries a ReDoS-safe certification. That matters for Java developers because critical in Java applications since the JVM regex engine uses backtracking and is susceptible to ReDoS without careful pattern design. RegexVault audits patterns against known backtracking attack vectors, ensuring you have the necessary context before using this regex in a high-stakes production environment.
Common Pitfalls
Taiwan (ROC) uses the Republic of China calendar — ROC 113 = 2024 (subtracting 1911). Government documents in Taiwan often use ROC year. Handle separately from PRC dates.
Technical Notes
Identical pattern to Japanese YYYY年MM月DD日 format. Both Chinese and Japanese use the same kanji/hanzi for year (年), month (月), and day (日). Context (locale) must determine which language is intended.
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