Scala. Eclipse. SBT crashes on pattern matching and say nothing. SBT bug? - scala

Question

Sorry for a long message - a hope, you'll read it.
I started to do my course work on Scala. It is FTP server. It is using patter-matching for command recognizing. I write my code in Eclipse. I think, SBT have a bug, but I don't know where to say about it.
Description:
Long compile time. After compilation there is no any error in IDE. But there is next line in "Problems" panel:
The SBT builder crashed while compiling your project. This is a bug in
the Scala compiler or SBT. Check the Erorr Log for details. The error
message is: ch.epfl.lamp.fjbg.JCode$OffsetTooBigException: offset too
big to fit in 16 bits: 38838 FTPDaemon Unknown Scala Problem
But program starts and works. Next error in run-time:
Exception in thread "main" java.lang.ClassFormatError: Truncated class
file at java.lang.ClassLoader.defineClass1(Native Method) at
java.lang.ClassLoader.defineClass(ClassLoader.java:787) at
java.security.SecureClassLoader.defineClass(SecureClassLoader.java:142)
at java.net.URLClassLoader.defineClass(URLClassLoader.java:447) at
java.net.URLClassLoader.access$100(URLClassLoader.java:71) at
java.net.URLClassLoader$1.run(URLClassLoader.java:361) at
java.net.URLClassLoader$1.run(URLClassLoader.java:355) at
java.security.AccessController.doPrivileged(Native Method) at
java.net.URLClassLoader.findClass(URLClassLoader.java:354) at
java.lang.ClassLoader.loadClass(ClassLoader.java:423) at
sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:308) at
java.lang.ClassLoader.loadClass(ClassLoader.java:356) at
org.egslava.ftp.ControlConnection.(ControlConnection.scala:14)
at org.egslava.ftp.Main$.main(Main.scala:38) at
org.egslava.ftp.Main.main(Main.scala)
This error is showed when I do
new ControlConnection().start();
ControlConnection use variable currentState (pointer to abstract class FtpState). Current state may be instance of DoLogin class or WaitForCommandsState class.
WaitForCommands contains next block of code:
message match{
case owner.Noop() => "200 NOOP ok\r\n";
case owner.User(_) => "530 Can't change from guest user\r\n";
case owner.Pass(_) => "230 Already logged in\r\n";
case owner.Pasv() => pasv() + "\r\n"; case owner.List() => list() + "\r\n";
case "condition" => "error";
case owner.Nlst() => nlst() + "\r\n";
case owner.TypeCMD() => ""//"200 Switching to binary mode\r\n";
case "PWD" => "257 \"" + currentDirectory + "\"\r\n";
case "SITE HELP" => "200-\r\n200\r\n";
case owner.Cwd(path) => "250 Directory successfuly changed\r\n";
case "condition2" => "error2"
case unrecognizedCommand => "500 Unrecognized command " + unrecognizedCommand + "\r\n";
}
If I comment string (any):
case "condition" => "error";
or
case "condition2" => "error2"
The error will disappear.
What is it?

Answer 1

There algorithm for compilation of pattern matching will fail on overly large case statements, by producing bytecode longer than the maximum allowed for a JVM class. As I understand it, this is to be fixed in Scala 2.10.