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When instrumenting different package, if it happens that they contains a
class with the same short name, all those class will be represented by a
single node.
This is due to the fact that the class javashot.graph.Graph only uses
classShortName to keep track of the nodes.
Solution: Provide a mechanism to detect this situation and add a prefix id
to the class short name for another class than the one already handled.

What steps will reproduce the problem?
 following the tutorial


What is the expected output? What do you see instead?
Caused by: java.lang.VerifyError: (class: XXX$$EnhancerByCGLIB$$b6bb4cb0, 
method: XXX signature: ()[XXX;) Inconsistent stack height 2 != 1


What version of the product are you using? On what operating system?
1.2 , Windows

Please provide any additional information below.

The instrumentation of multi-threaded application may produce a graph which
do not reflect the real execution.
This is due to the fact that the class javashot.graph.Graph uses static
attributes to keep track of the nodes.
Solution: Use ThreadLocal instead

Add the execution time of the method over the return arrow, the generated
graph will contains also some profiling data which can help in detecting
application's bottlenecks.

What steps will reproduce the problem?
1. Add a folder containing upper case letters in javassitExtraClassPath : 
myFolderPath
2. Start javashot

You should get a stack trace like this:
javassist.NotFoundException: myfolderpath/myjar.jar
    at javassist.JarClassPath.<init>(ClassPoolTail.java:134)
    at javassist.ClassPoolTail.makePathObject(ClassPoolTail.java:258)
    at javassist.ClassPoolTail.insertClassPath(ClassPoolTail.java:244)
    at javassist.ClassPool.insertClassPath(ClassPool.java:867)
    at javashot.instrumentation.GraphAgent.<clinit>(GraphAgent.java:38)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.
java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAcces
sorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at sun.instrument.InstrumentationImpl.loadClassAndStartAgent(Instrumenta
tionImpl.java:323)
    at sun.instrument.InstrumentationImpl.loadClassAndCallPremain(Instrument
ationImpl.java:338)
javassist.NotFoundException: myfolderpath/myjar.jar

Please notice that the path is all lower case!


I use version 1.2 on ubuntu 11.10. Unix systems are case sensitive!

The faulty code is in the javashot.util.Properties class:
public static ArrayList<String> getJavassitExtraClassPath() {
        String instrumentationClassPattern = (String) properties.get("javassitExtraClassPath");
        if (instrumentationClassPattern == null || instrumentationClassPattern.isEmpty()) {
            return null;
        }
        ArrayList<String> result = new ArrayList<String>();
        StringTokenizer tokens = new StringTokenizer(instrumentationClassPattern, ",");
        while (tokens.hasMoreElements()) {
            result.add(tokens.nextToken().trim().toLowerCase()); <---- HERE!
        }
        return result;
    }

If a program is running on a web application server such as JBoss and
Tomcat, the javassit's ClassPool object may not be able to find user
classes since such a web application server uses multiple class loaders as
well as the system class loader.
Solution: Add an entry in "javashot.properties" where we can specify the
location of those classes or jars