beanshell-死锁问题

Question

Has anyone got any experience of having deadlocks with beanshell? This is something we have been encountering recently in our production system where script execution is blocking other threads, due to it's lock on classloading via tomcat. The following is the stacktrace for the lock owner in thread dump:

"Thread-64" : 150 : BLOCKED : cpu=37812500000 : cpuLoad= 0.0
BlockedCount:93354 BlockedTime:-1 LockName:java.lang.Object@219d66b6 LockOwnerID:151 LockOwnerName:Thread-65
WaitedCount:13 WaitedTime:-1 InNative:false IsSuspended:false   at org.apache.catalina.webresources.AbstractSingleArchiveResourceSet.getArchiveEntries(AbstractSingleArchiveResourceSet.java:66)
    at org.apache.catalina.webresources.AbstractArchiveResourceSet.getResource(AbstractArchiveResourceSet.java:262)
    at org.apache.catalina.webresources.StandardRoot.getResourceInternal(StandardRoot.java:281)
    at org.apache.catalina.webresources.Cache.getResource(Cache.java:62)
    at org.apache.catalina.webresources.StandardRoot.getResource(StandardRoot.java:216)
    at org.apache.catalina.webresources.StandardRoot.getClassLoaderResource(StandardRoot.java:225)
    at org.apache.catalina.loader.WebappClassLoaderBase.findClassInternal(WebappClassLoaderBase.java:2173)
    at org.apache.catalina.loader.WebappClassLoaderBase.findClass(WebappClassLoaderBase.java:811)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1260)
    at org.apache.catalina.loader.WebappClassLoaderBase.loadClass(WebappClassLoaderBase.java:1119)
    at java.lang.Class.forName0(Class.java:-2)
    at java.lang.Class.forName(Class.java:348)
    at bsh.classpath.ClassManagerImpl.classForName(null:-1)
    at bsh.NameSpace.classForName(null:-1)
    at bsh.NameSpace.getImportedClassImpl(null:-1)
    at bsh.NameSpace.getClassImpl(null:-1)
    at bsh.NameSpace.getClass(null:-1)
    at bsh.Name.consumeNextObjectField(null:-1)
    at bsh.Name.toObject(null:-1)
    at bsh.BSHAmbiguousName.toObject(null:-1)
    at bsh.BSHAmbiguousName.toObject(null:-1)
    at bsh.BSHPrimaryExpression.eval(null:-1)
    at bsh.BSHPrimaryExpression.eval(null:-1)
    at bsh.BSHVariableDeclarator.eval(null:-1)
    at bsh.BSHTypedVariableDeclaration.eval(null:-1)
    at bsh.Interpreter.eval(null:-1)
    at bsh.Interpreter.eval(null:-1)
    at bsh.Interpreter.eval(null:-1)
    at my.package.MyClassFile(MyClassFile:2332)

I see that Groovy is a more popular choice for Java scripting, but I haven't seen many posts where it says that bsh can cause deadlocks.

It would be good to get some ideas from SO users.

Regards,

Answer 1

There's a fix for one dead lock in GUI does not start in Java 8 found in Beanshell (almost latest) version 2.0b5.

You can open a new issue in Beanshell project.

It may be connected to ClassManagerImpl :

Bsh has a multi-tiered class loading architecture. No class loader is created unless/until a class is generated, the classpath is modified, or a class is reloaded.

Note: we may need some synchronization in here