Why is exception.printStackTrace() considered bad practice?

The trip hazards of printStackTrace()

Throwable.printStackTrace() writes directly to System.err, skipping past any logging architecture in place. It's a bit like trying to carry a bowl of soup across a room of trampolines — mess everywhere.

Why log rotation matters

PrintStackTrace() doesn't handle log rotation. Logging frameworks have the ability to manage file size, rotation, and backup, preventing log files from spiraling out of control.

Thread safety and log chaos

PrintStackTrace() is not thread-safe, meaning that in a multi-threaded environment, log messages can intertwine, resulting in a log which looks like Spaghetti Junction at rush hour. Logging frameworks, however, handle thread-safety with easy panache, ensuring clean, separate log entries.

Beware of performance costs

Generating stack traces can be expensive, like ordering the entire menu at a Michelin-starred restaurant. Not generally a good move in performance-sensitive zones of your code base. Use lazy-logging for less impact on performance.

if (logger.isDebugEnabled()) {
    // If a tree falls in a debug forest and no logger is around, does it make a sound?
    logger.debug("Uh oh, error in sector 7G: ", expensiveOperation());
}
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Balancing user experience and error handling

It’s not wise to splatter stack traces in front of users. It's like showing them the blueprint of your house when they just need to know where the bathroom is. Display user-friendly messages, but keep the gruesome details for the logs.

catch (Exception e) {
    logger.error("Something broke, not your fault. Developers summoned.", e);
    userFacingComponent.displayError("We hit a snag. Our best people are on it.");
}
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Don't just print, handle!

Printing stack trace but not properly handling exceptions is like putting a band-aid on a broken pipe — not effective. Practice graceful error recovery. Sometimes, allow exceptions to climb up the ladder and be managed at a higher level might be the best strategy.

Keep your logs tidy

Being consistent and coherent in your logs is like keeping your desk tidy — It simplifies things! Make sure all exceptions and messages pass through your chosen logging framework—uniformity is key.

Debugging and the comedic "God's Perfect Exception"

Part humor, part philosophy, part biting reality - the concept of the "God's Perfect Exception" is that given enough coffee and pressure, every developer dreams of an exception which practically fixes itself.

catch (Throwable unexpected) {
    logger.fatal("The unexpected happened. Deity not available. ", unexpected);
}
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While we're waiting for that dream to become reality, logging unexpected exceptions is the best we've got.