Java Stack Trace Frame Regex for Python

What this pattern does

This page provides a comprehensive, battle-tested regular expression for matching java stack trace frame, ported and verified for Python. A rigorously tested regex reduces debugging time and protects your application from edge-case failures. The snippet below is ready to drop into your Python project — whether you're validating in a Django view, a FastAPI endpoint, or a standalone data processing script.

Python Implementation

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

import re

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

def validate_java_stack_trace_frame(value: str) -> bool:
    return bool(java_stack_trace_frame_pattern.fullmatch(value))

# Example
print(validate_java_stack_trace_frame("	at com.example.MyClass.myMethod(MyClass.java:42)"))  # True

Test Cases

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 Python developers because particularly important in Python web servers where CPU-bound regex operations can stall concurrent request handling. 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

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.