Stack traces when the start of a GBean fails

[John Sisson <jr...@gmail.com>]

Currently if the start of a GBean fails, an error with a stack trace is 
written to the log.

Sometimes the cause of the GBean failure is a common user error that 
does not require a stack trace for the user to rectify the problem.  An 
example of this is where a port is already in use and we get a 
BindException.  All the user really needs to be told is that Jetty or 
Tomcat was attempting to use port x and it was already in use.

Since BindExceptions are a common problem that new users may run into 
the first time they start Geronimo on their system, seeing a stack trace 
IMHO is not a good impression.  I have heard many people comment that 
they like Geronimo's startup because it doesn't output heaps of 
unncessary messages.  It would be nice if it still operated that way 
when users make a common mistake.

Could we introduce a new exception class e.g. GBeanLifecycleException 
that can be optionally used by GBeans (such the JettyConnector shown 
below) and change the code in the catch block of  
GBeanInstanceState.attemptFullStart(..) to check if the exception is an 
instance of GBeanLifecycleException and if so, call the method on the 
exception that returns whether the stack trace should be logged.

Comments or other ideas on how we could we improve the current code 
GBean code so that the start of a GBean can "optionally" result in a 
message being logged without a stack trace being logged.

An example of one of the stack traces the user would currently see:

09:08:35,375 ERROR [GBeanInstanceState] Error while starting; GBean is 
now in the FAILED state: objectName="geronimo.server:J2EEAppl
ication=null,J2EEModule=org/apache/geronimo/Jetty,J2EEServer=geronimo,j2eeType=GBean,name=JettyWebConnector"
java.net.BindException: Address already in use: JVM_Bind
        at java.net.PlainSocketImpl.socketBind(Native Method)
        at java.net.PlainSocketImpl.bind(PlainSocketImpl.java:331)
        at java.net.ServerSocket.bind(ServerSocket.java:318)
        at java.net.ServerSocket.<init>(ServerSocket.java:185)
        at 
org.mortbay.util.ThreadedServer.newServerSocket(ThreadedServer.java:391)
        at org.mortbay.util.ThreadedServer.open(ThreadedServer.java:477)
        at 
org.apache.geronimo.jetty.connector.JettyConnector.doStart(JettyConnector.java:203)
        at 
org.apache.geronimo.gbean.runtime.GBeanInstance.createInstance(GBeanInstance.java:936)
        at 
org.apache.geronimo.gbean.runtime.GBeanInstanceState.attemptFullStart(GBeanInstanceState.java:325)
        <SNIP>

Thanks,

John

Re: Stack traces when the start of a GBean fails

[Dain Sundstrom <da...@iq80.com>]

I used a similar trick in XBean and it worked well.  The problem I  
was having was, as you are starting the server different problems can  
occur, some are fatal and some are not.  In my original code I had  
system exits spread thought the boot code, which made it competely  
untestable.  As soon as I introduced an FatalStartupException, I  
could test the code.  My main method simply call the boot code,  
catches a fatal exception, prints the message, and exits with the  
exit code within the exception class.  IIRC, I set it up so the user  
needs to pass a flag to get the exception stack trace to print.

Anyway,  I suggest we introduce a logical exception hierarchy for  
startup errors, which capture the most common problems such as a bind  
error.  Then the boot code can decide (based on user flags maybe) if  
the error should be treated as fatal.

-dain

On Nov 30, 2005, at 3:52 PM, John Sisson wrote:

> Currently if the start of a GBean fails, an error with a stack  
> trace is written to the log.
>
> Sometimes the cause of the GBean failure is a common user error  
> that does not require a stack trace for the user to rectify the  
> problem.  An example of this is where a port is already in use and  
> we get a BindException.  All the user really needs to be told is  
> that Jetty or Tomcat was attempting to use port x and it was  
> already in use.
>
> Since BindExceptions are a common problem that new users may run  
> into the first time they start Geronimo on their system, seeing a  
> stack trace IMHO is not a good impression.  I have heard many  
> people comment that they like Geronimo's startup because it doesn't  
> output heaps of unncessary messages.  It would be nice if it still  
> operated that way when users make a common mistake.
>
> Could we introduce a new exception class e.g.  
> GBeanLifecycleException that can be optionally used by GBeans (such  
> the JettyConnector shown below) and change the code in the catch  
> block of  GBeanInstanceState.attemptFullStart(..) to check if the  
> exception is an instance of GBeanLifecycleException and if so, call  
> the method on the exception that returns whether the stack trace  
> should be logged.
>
> Comments or other ideas on how we could we improve the current code  
> GBean code so that the start of a GBean can "optionally" result in  
> a message being logged without a stack trace being logged.
>
> An example of one of the stack traces the user would currently see:
>
> 09:08:35,375 ERROR [GBeanInstanceState] Error while starting; GBean  
> is now in the FAILED state: objectName="geronimo.server:J2EEAppl
> ication=null,J2EEModule=org/apache/geronimo/ 
> Jetty,J2EEServer=geronimo,j2eeType=GBean,name=JettyWebConnector"
> java.net.BindException: Address already in use: JVM_Bind
>        at java.net.PlainSocketImpl.socketBind(Native Method)
>        at java.net.PlainSocketImpl.bind(PlainSocketImpl.java:331)
>        at java.net.ServerSocket.bind(ServerSocket.java:318)
>        at java.net.ServerSocket.<init>(ServerSocket.java:185)
>        at org.mortbay.util.ThreadedServer.newServerSocket 
> (ThreadedServer.java:391)
>        at org.mortbay.util.ThreadedServer.open(ThreadedServer.java: 
> 477)
>        at org.apache.geronimo.jetty.connector.JettyConnector.doStart 
> (JettyConnector.java:203)
>        at  
> org.apache.geronimo.gbean.runtime.GBeanInstance.createInstance 
> (GBeanInstance.java:936)
>        at  
> org.apache.geronimo.gbean.runtime.GBeanInstanceState.attemptFullStart( 
> GBeanInstanceState.java:325)
>        <SNIP>
>
> Thanks,
>
> John