ClassLoaderIClassLoader 's ClassNotFoundException handle mechanism enhancement

[gr4ve]

Class<?> clazz;
        try {
             clazz = Class.forName(Descriptor.toClassName(descriptor),
                           false, this.classLoader);
        } catch (ClassNotFoundException e) {
            if (e.getException() == null) {
                return null;
            } else
            {
                throw e;
            }
        }

in some osgi environment, the e.getException() will return a ClassNotFoundException too.
can we add an additional condition to handle above case?

Class<?> clazz;
        try {
             clazz = Class.forName(Descriptor.toClassName(descriptor),
                           false, this.classLoader);
        } catch (ClassNotFoundException e) {
            if (e.getException() == null || e.getException() instanceof ClassNotFoundException) {
                return null;
            } else
            {
                throw e;
            }
        }

[oontvoo]

Are you able to share the reproducible case?

I'm not sure it's a good idea to hide multiple upstream exceptions like this ... It could make debugging issues harder in the future

[aunkrig]

The aim is to distinguish between „Class does not exist“ and „exception when loading the class“, when the JRE maps both cases to ClassNotFoundException.

I‘ll change the code as requested (it is a good pattern to wrap exception X in another exception X in order to augment the message).

[aunkrig]

I fixed it:

            // Determine whether the class DOES NOT EXIST, or whether there were problems loading it. That's easier
            // said than done... the following seems to work:
            // (See also https://github.com/janino-compiler/janino/issues/104).
            {
                Throwable t = e.getCause();
                while (t instanceof ClassNotFoundException) t = t.getCause();
                if (t == null) return null;
            }

Please test!

[agroh1]

Thanks very much for this fix. I ran into this issue on a Spark cluster when using the old version and thought I would leave a stack trace so that people could find this issue more easily.

Caused by: org.codehaus.commons.compiler.CompileException: Line 11, Column 21: FunctionUtils
at org.codehaus.janino.UnitCompiler.findTypeByName(UnitCompiler.java:8473)
at org.codehaus.janino.UnitCompiler.reclassifyName(UnitCompiler.java:8712)
at org.codehaus.janino.UnitCompiler.reclassifyName(UnitCompiler.java:8381)
at org.codehaus.janino.UnitCompiler.reclassifyName(UnitCompiler.java:8384)
at org.codehaus.janino.UnitCompiler.reclassify(UnitCompiler.java:8244)
at org.codehaus.janino.UnitCompiler.getType2(UnitCompiler.java:6768)
at org.codehaus.janino.UnitCompiler.access$14100(UnitCompiler.java:215)
at org.codehaus.janino.UnitCompiler$21$2$1.visitAmbiguousName(UnitCompiler.java:6410)
at org.codehaus.janino.UnitCompiler$21$2$1.visitAmbiguousName(UnitCompiler.java:6407)
at org.codehaus.janino.Java$AmbiguousName.accept(Java.java:4213)
at org.codehaus.janino.UnitCompiler$21$2.visitLvalue(UnitCompiler.java:6407)
at org.codehaus.janino.UnitCompiler$21$2.visitLvalue(UnitCompiler.java:6403)
at org.codehaus.janino.Java$Lvalue.accept(Java.java:4137)
at org.codehaus.janino.UnitCompiler$21.visitRvalue(UnitCompiler.java:6403)
at org.codehaus.janino.UnitCompiler$21.visitRvalue(UnitCompiler.java:6382)
at org.codehaus.janino.Java$Rvalue.accept(Java.java:4105)
at org.codehaus.janino.UnitCompiler.getType(UnitCompiler.java:6382)
at org.codehaus.janino.UnitCompiler.findIMethod(UnitCompiler.java:8939)
at org.codehaus.janino.UnitCompiler.compileGet2(UnitCompiler.java:5060)
at org.codehaus.janino.UnitCompiler.access$9100(UnitCompiler.java:215)
at org.codehaus.janino.UnitCompiler$16.visitMethodInvocation(UnitCompiler.java:4421)
at org.codehaus.janino.UnitCompiler$16.visitMethodInvocation(UnitCompiler.java:4394)

Caused by: java.lang.ClassNotFoundException: FunctionUtils
at org.apache.spark.repl.ExecutorClassLoader.findClass(ExecutorClassLoader.scala:84)
at java.lang.ClassLoader.loadClass(ClassLoader.java:419)
at java.lang.ClassLoader.loadClass(ClassLoader.java:352)
at java.lang.Class.forName0(Native Method)
at java.lang.Class.forName(Class.java:348)
at org.codehaus.janino.ClassLoaderIClassLoader.findIClass(ClassLoaderIClassLoader.java:89)
at org.codehaus.janino.IClassLoader.loadIClass(IClassLoader.java:312)
at org.codehaus.janino.UnitCompiler.findTypeByName(UnitCompiler.java:8469)
... 127 more
Caused by: java.lang.ClassNotFoundException: FunctionUtils
at java.lang.ClassLoader.findClass(ClassLoader.java:524)
at org.apache.spark.util.ParentClassLoader.findClass(ParentClassLoader.scala:26)
at java.lang.ClassLoader.loadClass(ClassLoader.java:419)
at org.apache.spark.util.ParentClassLoader.loadClass(ParentClassLoader.scala:34)
at java.lang.ClassLoader.loadClass(ClassLoader.java:352)
at org.apache.spark.util.ParentClassLoader.loadClass(ParentClassLoader.scala:30)
at org.apache.spark.repl.ExecutorClassLoader.findClass(ExecutorClassLoader.scala:79)
... 134 more