How to get Java Call Stack of a running application

Question

I am working on very huge java web based application. As there is no proper logging done while development so its very difficult for me to put break point and debug the app as i dont know execution order. Is there any mechanism to get complete Call Stack of the the running java application after I perform some actions.

I searched it on net for long time but cannot came to concrete solution. Please suggest me if something is there for it. Thanks

Answer 1

Method 1: Use jstack utility from command line (part of the JDK distro).

Method 2: Send signal 3 to the java process, it will dump stack traces on stdout.

Method 3: Call Thread.getAllStackTraces () from within application:

public class StackTraceDumper
{
    public static dumpAllStackTraces ()
    {
        for (Map.Entry <Thread, StackTraceElement []> entry: 
            Thread.getAllStackTraces().entrySet ())
        {
            System.out.println (entry.getKey ().getName () + ":");
            for (StackTraceElement element: entry.getValue ())
                System.out.println ("\t" + element);
        }
    }
}

Then use StackTraceDumper.dumpAllStackTraces() where you need to dump stack traces.

Answer 2

Thread.dumpStack() Prints a stack trace of the current thread to the standard error stream. Thread.getAllStackTraces() Returns a map of stack traces for all live threads. Thread.getStackTrace() Returns an array of stack trace elements representing the stack dump of this thread.