FindBugs can't locate org.apache.bcel.classfile.ClassFormatException

ant, fedora, findbugs, java, linux

Solution

You need an `<Auxclasspath/>` subentity pointing to the classpath you used when you compiled. Findbugs uses the built `*.class` files, and needs the source to pinpoint in the source code where an error is, the classes you're analyzing, and the classpath to all of your third party jars to be able to understand the code:

 <findbugs
     home="${findbugs.home}" 
     output="xml" 
     outputFile="bcel-fb.xml">
     <auxClasspath refid="main.classpath"/>  <!-- Third party jars classpath   -->
     <class location="${main.destdir}"/>     <!-- Class files you're analyzing -->
     <sourcePath path="${main.srcdir}"/>     <!-- Source directory             -->
 </findbugs>

By the way, you should put the findbugs jar inside your project (My preference would be under `${basedir}/antlib/findbugs`) and use that in your `<taskdef/>`:

<taskdef name="findbugs" 
    classname="edu.umd.cs.findbugs.anttask.FindBugsTask">
    <classpath>
       <fileset dir="${basedir}/antlib/findbugs"/>
    </classpath>
</taskdef>

This way, Findbugs is part of your project. Anyone who checks out your project will automatically have the findbugs jar and will be able to run your findbugs task without having to download the jar and installing it in `$ANT_HOME/lib`.

I do this with any optional Ant task jars like PMD, Checkstyle, and Ant-Contrib. It makes it much easier for others to be able to run my builds, and I spend less time trying to explain to people where they can get that jar, and how to install it. Plus, if you use a Continuous Build system like Jenkins, you don't have to futz with the server anytime you add in a new optional jar.

Problem

I installed the Fedora 20 findbugs RPMs, and set up my Ant `build.xml` file thusly: ``` <property name="findbugs.home" location="/usr/share/findbugs"/> <target name="findbugs" description="static bytecode analysis"> <taskdef name="findbugs" classname="edu.umd.cs.findbugs.anttask.FindBugsTask"> </taskdef> <findbugs home="${findbugs.home}" output="xml" outputFile="bcel-fb.xml"> <sourcePath path="${src.dir}"/> <fileset dir="${build.dir}"> <include name="**/*.class"/> </fileset> </findbugs> </target> ``` This gives me the error: java.lang.IllegalArgumentException: Can't find findbugs.jar in /usr/share/findbugs/lib So I make `/usr/share/findbugs/lib` a symbolic link to `/usr/share/java`, where `findbugs.jar` lives. That gets me a bit further, but now it spits out: ``` findbugs: [findbugs] Executing findbugs from ant task [findbugs] Running FindBugs... [findbugs] Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/bcel/classfile/ClassFormatException ``` `strace` shows that it found and opened `/usr/share/java/findbugs-bcel.jar`, so I have no idea why it can't load the class. Explicitly adding `/usr/share/java/findbugs-bcel.jar` to the taskdef's classpath doesn't change anything. NOTE: I'm not trying to run FindBugs on BCEL. BCEL is used by FindBugs to do its analysis, and my own code doesn't use BCEL at all.

Original source