title: Findbugs with Gradle plugin doesn't work in Java 9
body: <p>I am migrating my project (multi project in <code>Gradle</code>) from Java 8 to Java 9 (without using modules so far). I use Gradle 4.3 and Findbugs Gradle plugin - I have <code>apply plugin: 'findbugs'</code> in my <code>gradle.build</code> file. In dependencies I have</p>
  
  <pre><code>compile group: 'com.google.code.findbugs', name: 'jsr305', version: '3.0.2'
  compile group: 'com.google.code.findbugs', name: 'annotations', version: '3.0.1'
  </code></pre>
  
  <p>Previously, with <code>java 8</code> (<code>open-jdk</code>) everything worked normally, but when I used <code>java 9</code> (<code>oracle - build 9.0.1+11</code>), I got the following exception after executing <code>gradle check</code> (<code>com.example.custom.MyClass</code> is a class from my codebase):
      The following errors occurred during analysis:</p>
  
  <pre><code>Error scanning com/example/custom/MyClass for referenced classes
  java.lang.IllegalArgumentException
    At org.objectweb.asm.ClassReader.&lt;init&gt;(ClassReader.java:170)
    At org.objectweb.asm.ClassReader.&lt;init&gt;(ClassReader.java:153)
    At edu.umd.cs.findbugs.asm.FBClassReader.&lt;init&gt;(FBClassReader.java:35)
    At edu.umd.cs.findbugs.classfile.engine.asm.ClassReaderAnalysisEngine.analyze(ClassReaderAnalysisEngine.java:48)
    At edu.umd.cs.findbugs.classfile.engine.asm.ClassReaderAnalysisEngine.analyze(ClassReaderAnalysisEngine.java:34)
    At edu.umd.cs.findbugs.classfile.impl.AnalysisCache.getClassAnalysis(AnalysisCache.java:262)
    At edu.umd.cs.findbugs.classfile.engine.ClassInfoAnalysisEngine.analyze(ClassInfoAnalysisEngine.java:75)
    At edu.umd.cs.findbugs.classfile.engine.ClassInfoAnalysisEngine.analyze(ClassInfoAnalysisEngine.java:38)
    At edu.umd.cs.findbugs.classfile.impl.AnalysisCache.getClassAnalysis(AnalysisCache.java:262)
    At edu.umd.cs.findbugs.FindBugs2.buildReferencedClassSet(FindBugs2.java:774)
    At edu.umd.cs.findbugs.FindBugs2.execute(FindBugs2.java:222)
    At org.gradle.api.plugins.quality.internal.findbugs.FindBugsExecuter.runFindbugs(FindBugsExecuter.java:39)
    At java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    At java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    At java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    At java.base/java.lang.reflect.Method.invoke(Method.java:564)
    At org.gradle.process.internal.worker.request.WorkerAction.run(WorkerAction.java:100)
    At org.gradle.process.internal.worker.request.WorkerAction.runThenStop(WorkerAction.java:83)
    At java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    At java.base/jdk.internal.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    At java.base/jdk.internal.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    At java.base/java.lang.reflect.Method.invoke(Method.java:564)
    At org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:35)
    At org.gradle.internal.dispatch.ReflectionDispatch.dispatch(ReflectionDispatch.java:24)
    At org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:146)
    At org.gradle.internal.remote.internal.hub.MessageHubBackedObjectConnection$DispatchWrapper.dispatch(MessageHubBackedObjectConnection.java:128)
    At org.gradle.internal.remote.internal.hub.MessageHub$Handler.run(MessageHub.java:404)
    At org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
    At org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
    At java.base/java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1167)
    At java.base/java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:641)
    At org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
    At java.base/java.lang.Thread.run(Thread.java:844)
  </code></pre>
  
  <p>This appears for every class from my gradle project (and also for every class which Hibernate JPA 2 Metamodel generator generated).
  I guess this will be related to jigsaw modules. However I don't declare any <code>module-info.java</code>, so I guess an automatic module is created for the whole codebase and everything is accessible from anywhere.</p>