log4j not printing the stacktrace for exceptions

Question

I am using log4j with tomcat. When I log exceptions in my JSPs, servlets:

private Logger _log = Logger.getLogger(this.getClass());
...
try{...} catch (Except         


        

Answer 1

There are two overloaded methods for error method.

1. logger.error(ex);
2. logger.error("some oops string ", ex);

if you use 1st method , which will only print the name of the Exception. if you use 2nd method, some message along with exception which will print complete stack trace similar to e.printStackTrace() method.

Answer 2

I haven't used the fillStackTrace call, so I cannot comment if that will work. Another approach is to use a little method that returns the formatted text from an Exception.

public static String getStackTrace(Exception e)
{
    StringWriter sWriter = new StringWriter();
    PrintWriter pWriter = new PrintWriter(sWriter);
    e.printStackTrace(pWriter);
    return sWriter.toString();
}

In your logging code, you could write:

logger.error("An exception occurred: " + Utils.getStackTrace(e));