JMH AnnotationProcessor NullPointerException

Question

我按照JMH主页中的指定创建了maven原型项目。当我对生成的项目进行maven构建时，我得到了“注释生成器抛出了异常. java.lang.NullPointerException”。我的java文件是

    public class MyBenchMark
     //   extends Benchmark
{
    @GenerateMicroBenchmark
    public void timeMyOperation(int reps) {
        for (int i = 0; i < reps; i++) {
          //  ConcurrentHashMapTest.populateConcurrenctHashMap();
        }
    }

    public static void main(String args[]) throws RunnerException {
        MyBenchMark myBenchMark = new MyBenchMark();
     //   myBenchMark.timeMyOperation(50);


        Options opt = new OptionsBuilder()
                .include(".*" + MyBenchMark.class.getSimpleName() + ".*")
                .forks(1)
                .build();

        new Runner(opt).run();
    }

} 

`。我得到的例外是

    org.apache.maven.lifecycle.LifecycleExecutionException: Failed to execute goal org.apache.maven.plugins:maven-compiler-plugin:3.0:compile (default-compile) on project perftest: Compilation failure
error: Annotation generator had thrown the exception. java.lang.NullPointerException

    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:213)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:153)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:145)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:84)
    at org.apache.maven.lifecycle.internal.LifecycleModuleBuilder.buildProject(LifecycleModuleBuilder.java:59)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.singleThreadedBuild(LifecycleStarter.java:183)
    at org.apache.maven.lifecycle.internal.LifecycleStarter.execute(LifecycleStarter.java:161)
    at org.apache.maven.DefaultMaven.doExecute(DefaultMaven.java:320)
    at org.apache.maven.DefaultMaven.execute(DefaultMaven.java:156)
    at org.apache.maven.cli.MavenCli.execute(MavenCli.java:537)
    at org.apache.maven.cli.MavenCli.doMain(MavenCli.java:196)
    at org.apache.maven.cli.MavenCli.main(MavenCli.java:141)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launchEnhanced(Launcher.java:290)
    at org.codehaus.plexus.classworlds.launcher.Launcher.launch(Launcher.java:230)
    at org.codehaus.plexus.classworlds.launcher.Launcher.mainWithExitCode(Launcher.java:409)
    at org.codehaus.plexus.classworlds.launcher.Launcher.main(Launcher.java:352)
    at org.codehaus.classworlds.Launcher.main(Launcher.java:47)
    at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    at java.lang.reflect.Method.invoke(Method.java:597)
    at com.intellij.rt.execution.application.AppMain.main(AppMain.java:120)
Caused by: org.apache.maven.plugin.compiler.CompilationFailureException: Compilation failure
error: Annotation generator had thrown the exception. java.lang.NullPointerException

    at org.apache.maven.plugin.compiler.AbstractCompilerMojo.execute(AbstractCompilerMojo.java:745)
    at org.apache.maven.plugin.compiler.CompilerMojo.execute(CompilerMojo.java:118)
    at org.apache.maven.plugin.DefaultBuildPluginManager.executeMojo(DefaultBuildPluginManager.java:101)
    at org.apache.maven.lifecycle.internal.MojoExecutor.execute(MojoExecutor.java:209)
    ... 25 more

Answer 1

int reps是JMH旅行的对象。根据GenerateMicroBenchmark Javadoc：“参数应该是零或多个包含状态的类。有关确切的合同，请参阅状态文档。”从参数中删除int reps，应该会很好。顺便说一句，您对基准测试的操作是有问题的，请先阅读JMH样品。

在这方面，错误信息应该会更好。