REGEXVAULTv2.0
Dev & Systems/Log Parsing
Verified Safe

Java Stack Trace Frame Regex for Java

/^\s+at ([a-zA-Z_$][a-zA-Z0-9_$]*(?:\.[a-zA-Z_$][a-zA-Z0-9_$]*)+)\.([a-zA-Z_$<>][a-zA-Z0-9_$<>]*)\(([a-zA-Z_$][a-zA-Z0-9_$]*\.java|Native Method|Unknown Source)(?::([0-9]+))?\)$/

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching java stack trace frame, 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

Java
// Java Stack Trace Frame
// ReDoS-safe | RegexVault — Dev & Systems > Log Parsing

import java.util.regex.Pattern;

public class JavaStackTraceFrameValidator {
    private static final Pattern PATTERN =
        Pattern.compile("^\\s+at ([a-zA-Z_$][a-zA-Z0-9_$]*(?:\\.[a-zA-Z_$][a-zA-Z0-9_$]*)+)\\.([a-zA-Z_$<>][a-zA-Z0-9_$<>]*)\\(([a-zA-Z_$][a-zA-Z0-9_$]*\\.java|Native Method|Unknown Source)(?::([0-9]+))?\\)$");

    public static boolean validate(String input) {
        return PATTERN.matcher(input).matches();
    }

    // Example
    public static void main(String[] args) {
        System.out.println(validate("	at com.example.MyClass.myMethod(MyClass.java:42)")); // true
    }
}

Test Cases

Matches (Valid)
Rejects (Invalid)
at com.example.MyClass.myMethod(MyClass.java:42)at com.example.Class.method(File.java:10)
at java.lang.Thread.run(Thread.java:833)com.example.Class.method(File.java:10)
at com.example.App.<init>(App.java:10) at bad format
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)

When to use this pattern

This pattern is drawn from the Dev & Systems > Log Parsing 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

Lambda expressions and anonymous classes appear as ClassName$$Lambda$N or ClassName$1. The $ in class names must be in character classes.

Technical Notes

Groups: 1=FQCN, 2=method name, 3=source file or 'Native Method'/'Unknown Source', 4=line number. Leading whitespace is required. <init> and <clinit> are valid method names.

Have a pattern that belongs in the vault?

Submit it for review — community-verified patterns get credited to your GitHub handle. Free submissions join the queue. Priority review available for $15.

Submit a Pattern