Cleaning noise out of Java stack traces

Question

My Java stack traces have a lot of entries that I don\'t care about, showing method invocation going through proxies and Spring reflection methods and stuff like that. It ca

Answer 1

For log4j:

package package1;

public class FilteringThrowableRenderer implements ThrowableRenderer {
    private static final String PACKAGES_SEPARATOR = "\\s*,\\s*";

    private final static String TRACE_PREFIX = "\tat ";

    private static final String FILTERED_WARNING = " [Stacktrace is filtered]";

    ThrowableRenderer defaultRenderer = new EnhancedThrowableRenderer();

    List skippedLinePrefixes;

    public FilteringThrowableRenderer() {
        String skippedPackagesString = "java,org"; // TODO: move it to config
        String[] skippedPackages =
            skippedPackagesString.trim().split(PACKAGES_SEPARATOR);
        skippedLinePrefixes = new ArrayList(skippedPackages.length);
        for (String packageName : skippedPackages) {
            skippedLinePrefixes.add(TRACE_PREFIX + packageName);
        }
    }

    @Override
    public String[] doRender(Throwable throwable) {
        String[] initialTrace = defaultRenderer.doRender(throwable);
        if (!skippedLinePrefixes.isEmpty()) {
            List result = new ArrayList(initialTrace.length);

            boolean filtered = false;
            trace: for (String element : initialTrace) {
                for (String skippedLinePrefix : skippedLinePrefixes) {
                    if (element.startsWith(skippedLinePrefix)) {
                        filtered = true;
                        continue trace;
                    }
                }
                result.add(element);
            }
            if (filtered && result.size() > 0) {
                result.set(0, result.get(0) + FILTERED_WARNING);
            }
            return result.toArray(new String[result.size()]);
        } else {
            return initialTrace;
        }
    }
}

to enable it with code:

ThrowableRendererSupport loggerRepository =
    (ThrowableRendererSupport) LogManager.getLoggerRepository();
loggerRepository.setThrowableRenderer(new FilteringThrowableRenderer());

or with log4j.properties:

log4j.throwableRenderer=package1.FilteringThrowableRenderer