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Architecture Sample via Java Stacktrace Analysis

Once I went to my friend's website and tried to open a page... and see what I got:

org.firebirdsql.jdbc.FBSQLException: Resource Exception. Unable to complete network request to host "".
Reason: Unable to complete network request to host "".
	at org.firebirdsql.jdbc.AbstractConnection.ensureInTransaction(AbstractConnection.java:842)
	at org.firebirdsql.jdbc.AbstractStatement.executeQuery(AbstractStatement.java:155)
	at helpers.ExtFunc.GetObjectId(ExtFunc.java:53)
	at BaseImpl.Init(BaseImpl.java:51)
	at Catalog$Impl.process(Catalog.java:325)
	at Catalog.service(Catalog.java:389)
	at sasta.ServletBase.service(ServletBase.java:136)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:588)
	at org.apache.jserv.JServConnection.processRequest(JServConnection.java:317)
	at org.apache.jserv.JServConnection.run(JServConnection.java:188)
	at java.lang.Thread.run(Thread.java:534)
at org.firebirdsql.gds.GDSException: Unable to complete network request to host "".
	at org.firebirdsql.jgds.GDS_Impl.isc_start_transaction(GDS_Impl.java:555)
	at org.firebirdsql.jca.FBManagedConnectionFactory.getCurrentIscTrHandle(FBManagedConnectionFactory.java:507)
	at org.firebirdsql.jca.FBManagedConnection.findIscTrHandle(FBManagedConnection.java:1125)
	at org.firebirdsql.jca.FBManagedConnection.internalStart(FBManagedConnection.java:675)
	at org.firebirdsql.jca.FBLocalTransaction.internalBegin(FBLocalTransaction.java:111)
	at org.firebirdsql.jca.FBLocalTransaction.begin(FBLocalTransaction.java:94)
	at org.firebirdsql.jdbc.AbstractConnection.ensureInTransaction(AbstractConnection.java:838)
	at org.firebirdsql.jdbc.AbstractStatement.executeQuery(AbstractStatement.java:155)
	at helpers.ExtFunc.GetObjectId(ExtFunc.java:53)
	at BaseImpl.Init(BaseImpl.java:51)
	at Catalog$Impl.process(Catalog.java:325)
	at Catalog.service(Catalog.java:389)
	at sasta.ServletBase.service(ServletBase.java:136)
	at javax.servlet.http.HttpServlet.service(HttpServlet.java:588)
	at org.apache.jserv.JServConnection.processRequest(JServConnection.java:317)
	at org.apache.jserv.JServConnection.run(JServConnection.java:188)
	at java.lang.Thread.run(Thread.java:534)

So, What happened here:

  • Apache web server gets a request, and calls a service
  • The service calls someone named sasta
  • Sasta starts looking up for a service in a catalog
  • the catalog has a class which name ends with Impl, which means this is a Working Class, and he tells the worker: work!
  • this poor Impl, he won't work until his Base Class, BaseImpl (a Base Worker) is initiated
  • now our Base Worker has no choice but to start doing something; here what he does:
    • it has Helpers, and it calls its helpers, which are not simple guys, they have functions, ExtFunc
    • Base Worker asks his Helpers Functions to tell him Object Identifier
    • the Functions, judging by their naming style, were written by a runaway c# programmer
    • to learn the Object Identifier Helpers had to go to the Database
    • to talk to the Database, they had to concoct a spell in the database language (which is SQL)
    • Helpers now say this spell and they want a Firebird to do some magic
      • now the Firebird starts thinking...
      • even with the magic sql spell it cannot tell the Object Identifier except in a Transaction
      • so the Firebird tries to open a Transaction
      • where's a Transaction, there's a Security, NSA, Java Cryptography Architecture; yes, a Firbird can talk to NSA
        • NSA Cryptographers allow to start a Transaction, actually they start it themselves
        • to do that, Cryptographers first have to start an Internal Transaction
        • but since they cannot start an Internal Transaction without notifying their management,
        • Cryptographers dare to bother their Management
          • Cryptographers Manager is actually a nice guy, and he starts an internal operation, internalStart
          • but he is a Manager! He cannot just do the job without checking whether maybe somebody else already did it
          • so the Manager starts looking around for someone who already did it before
          • he wants to start an operation called findIscTrHandle
          • being a Manager, he cannot do two action items in one day (or else he would have been an Engineer)
          • so the Manager wants to know what are his Cryptographers doing right now
          • and he starts the operation called getCurrentIscTrHandle
          • the Manager does not do this operation himself, but sends the request to the people responsible for this kind of job
            • the Responsible Ones, they get an action item to do
            • so they start a Transaction, via isc_start_transaction
            • they do it in a separate Thread, because they are some kind of independent contractors
            • in this new Thread, they are trying to figure out, what exactly should they do?
            • and while discussing this, they figure out that the name of the Request Owner is empty. An empty string. Just imagine if your name were "". That would have caused a lot of fun in an "Information System". Our system, in our company, until recently, did not even accept two-letter names, like, say "He", "Mo", "Li", or even worse, "Ng".
            • so the Contractors just laugh at the Manager, telling him to buzz off
          • the Manager, having got this refusal, tells his Cryptographers to buzz off
        • Cryptographers tell the Helpers to buzz off
      • Helpers tell the Base Worker to buzz off
    • Base Worker does not bother the SubWorker, and tells the Service to buzz off
  • and the Server publishes all this bureaucracy, because *your name string is empty"

Wha?

That's Java architecture in its typical implementation.