Failure when analyzing a module-info.java

[Chris Povirk]

We should be able to fix it with something like:

if (symbol.getKind().name().equals("MODULE")) {
  return false;
}

(I'm comparing strings, instead of the Kind values themselves, so that the code can work with javac8.)

The error, which I saw when experimenting with a module-info.java in jimfs:

 error-prone version: 2.3.3
 BugPattern: BetaApi
 Stack Trace:
 java.lang.NullPointerException
at jdk.compiler/com.sun.tools.javac.code.Symbol.packge(Symbol.java:500)
at com.google.common.annotations.checkers.AnnotatedApiUsageChecker.isInMatchingPackage(AnnotatedApiUsageChecker.java:106)
at com.google.common.annotations.checkers.AnnotatedApiUsageChecker.matchTree(AnnotatedApiUsageChecker.java:88)
at com.google.common.annotations.checkers.AnnotatedApiUsageChecker.matchMemberSelect(AnnotatedApiUsageChecker.java:71)
at com.google.errorprone.scanner.ErrorProneScanner.processMatchers(ErrorProneScanner.java:433)
at com.google.errorprone.scanner.ErrorProneScanner.visitMemberSelect(ErrorProneScanner.java:712)
at com.google.errorprone.scanner.ErrorProneScanner.visitMemberSelect(ErrorProneScanner.java:150)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCFieldAccess.accept(JCTree.java:2118)
at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:82)
at com.google.errorprone.scanner.Scanner.scan(Scanner.java:71)
at com.google.errorprone.scanner.Scanner.scan(Scanner.java:45)
at jdk.compiler/com.sun.source.util.TreeScanner.visitRequires(TreeScanner.java:880)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCRequires.accept(JCTree.java:2853)
at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:82)
at com.google.errorprone.scanner.Scanner.scan(Scanner.java:71)
at com.google.errorprone.scanner.Scanner.scan(Scanner.java:45)
at jdk.compiler/com.sun.source.util.TreeScanner.scan(TreeScanner.java:105)
at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:113)
at jdk.compiler/com.sun.source.util.TreeScanner.visitModule(TreeScanner.java:853)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCModuleDecl.accept(JCTree.java:2702)
at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:82)
at com.google.errorprone.scanner.Scanner.scan(Scanner.java:71)
at com.google.errorprone.scanner.Scanner.scan(Scanner.java:45)
at jdk.compiler/com.sun.source.util.TreeScanner.scan(TreeScanner.java:105)
at jdk.compiler/com.sun.source.util.TreeScanner.scanAndReduce(TreeScanner.java:113)
at jdk.compiler/com.sun.source.util.TreeScanner.visitCompilationUnit(TreeScanner.java:144)
at com.google.errorprone.scanner.ErrorProneScanner.visitCompilationUnit(ErrorProneScanner.java:546)
at com.google.errorprone.scanner.ErrorProneScanner.visitCompilationUnit(ErrorProneScanner.java:150)
at jdk.compiler/com.sun.tools.javac.tree.JCTree$JCCompilationUnit.accept(JCTree.java:591)
at jdk.compiler/com.sun.source.util.TreePathScanner.scan(TreePathScanner.java:56)
at com.google.errorprone.scanner.Scanner.scan(Scanner.java:55)
at com.google.errorprone.scanner.ErrorProneScannerTransformer.apply(ErrorProneScannerTransformer.java:43)
at com.google.errorprone.ErrorProneAnalyzer.finished(ErrorProneAnalyzer.java:147)
at jdk.compiler/com.sun.tools.javac.api.MultiTaskListener.finished(MultiTaskListener.java:120)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1391)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.flow(JavaCompiler.java:1338)
at jdk.compiler/com.sun.tools.javac.main.JavaCompiler.compile(JavaCompiler.java:931)
at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.lambda$doCall$0(JavacTaskImpl.java:100)
at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.handleExceptions(JavacTaskImpl.java:142)
at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.doCall(JavacTaskImpl.java:96)
at jdk.compiler/com.sun.tools.javac.api.JavacTaskImpl.call(JavacTaskImpl.java:90)
at org.codehaus.plexus.compiler.javac.JavaxToolsCompiler.compileInProcess(JavaxToolsCompiler.java:126)
at org.codehaus.plexus.compiler.javac.JavacCompiler.performCompile(JavacCompiler.java:174)
at org.apache.maven.plugin.compiler.AbstractCompilerMojo.execute(AbstractCompilerMojo.java:1129)
at org.apache.maven.plugin.compiler.CompilerMojo.execute(CompilerMojo.java:188)
at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:134)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:208)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:154)
at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:146)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:117)
at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:81)
at org.apache.maven.lifecycle.internal.builder.singlethreaded.SingleThreadedBuilder.build(SingleThreadedBuilder.java:51)
at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:128)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:309)
at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:194)
at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:107)
at org.apache.maven.cli.MavenCli.execute(MavenCli.java:993)
at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:345)
at org.apache.maven.cli.MavenCli.main(MavenCli.java:191)
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:566)
at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:289)
at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:229)
at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:415)
at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:356)

This is somewhat similar to the module-induced error reported in google/error-prone#1240