Selenium：注释类型不适用于此类声明

Question

我没有正确使用@FindBy注释吗？

package dur.bounceme.net.SeleniumBase;

import java.util.logging.Logger;
import org.openqa.selenium.WebDriver;
import org.openqa.selenium.WebElement;
import org.openqa.selenium.support.FindBy;
import org.openqa.selenium.support.How;
import org.openqa.selenium.support.ui.Select;

class WelcomePage {

    private static final Logger LOG = Logger.getLogger(App.class.getName());
    private WebDriver webDriver = null;

    private WelcomePage() {
    }

    WelcomePage(WebDriver webDriver) {
        this.webDriver = webDriver;
        LOG.info(webDriver.getCurrentUrl());
    }

    static WelcomePage init(WebDriver webDriver) {
        return new WelcomePage(webDriver);
    }

    void populateCatalogue() {
        @FindBy(partialLinkText = "Books")
        WebElement books;
    }

}

编译错误：

thufir@dur:~/NetBeansProjects/com.toscrape.books.selenium$ 
thufir@dur:~/NetBeansProjects/com.toscrape.books.selenium$ gradle clean compileJava --stacktrace

> Task :compileJava FAILED
/home/thufir/NetBeansProjects/com.toscrape.books.selenium/src/main/java/dur/bounceme/net/SeleniumBase/WelcomePage.java:28: error: annotation type not applicable to this kind of declaration
        @FindBy(partialLinkText = "Books")
        ^
1 error

FAILURE: Build failed with an exception.

* What went wrong:
Execution failed for task ':compileJava'.
> Compilation failed; see the compiler error output for details.

* Try:
Run with --info or --debug option to get more log output. Run with --scan to get full insights.

* Exception is:
org.gradle.api.tasks.TaskExecutionException: Execution failed for task ':compileJava'.
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:96)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.execute(ExecuteActionsTaskExecuter.java:65)
        at org.gradle.api.internal.tasks.execution.ActionEventFiringTaskExecuter.execute(ActionEventFiringTaskExecuter.java:44)
        at org.gradle.api.internal.tasks.execution.TimeoutTaskExecuter.execute(TimeoutTaskExecuter.java:53)
        at org.gradle.api.internal.tasks.execution.SnapshotAfterExecutionTaskExecuter.execute(SnapshotAfterExecutionTaskExecuter.java:38)
        at org.gradle.api.internal.tasks.execution.OutputDirectoryCreatingTaskExecuter.execute(OutputDirectoryCreatingTaskExecuter.java:51)
        at org.gradle.api.internal.tasks.execution.SkipUpToDateTaskExecuter.execute(SkipUpToDateTaskExecuter.java:59)
        at org.gradle.api.internal.tasks.execution.ResolveTaskOutputCachingStateExecuter.execute(ResolveTaskOutputCachingStateExecuter.java:49)
        at org.gradle.api.internal.tasks.execution.ValidatingTaskExecuter.execute(ValidatingTaskExecuter.java:61)
        at org.gradle.api.internal.tasks.execution.SkipEmptySourceFilesTaskExecuter.execute(SkipEmptySourceFilesTaskExecuter.java:101)
        at org.gradle.api.internal.tasks.execution.CleanupStaleOutputsExecuter.execute(CleanupStaleOutputsExecuter.java:91)
        at org.gradle.api.internal.tasks.execution.FinalizePropertiesTaskExecuter.execute(FinalizePropertiesTaskExecuter.java:44)
        at org.gradle.api.internal.tasks.execution.ResolveTaskArtifactStateTaskExecuter.execute(ResolveTaskArtifactStateTaskExecuter.java:62)
        at org.gradle.api.internal.tasks.execution.SkipTaskWithNoActionsExecuter.execute(SkipTaskWithNoActionsExecuter.java:55)
        at org.gradle.api.internal.tasks.execution.SkipOnlyIfTaskExecuter.execute(SkipOnlyIfTaskExecuter.java:54)
        at org.gradle.api.internal.tasks.execution.CatchExceptionTaskExecuter.execute(CatchExceptionTaskExecuter.java:35)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter$1.run(EventFiringTaskExecuter.java:49)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:301)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:293)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:175)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:91)
        at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
        at org.gradle.api.internal.tasks.execution.EventFiringTaskExecuter.execute(EventFiringTaskExecuter.java:44)
        at org.gradle.execution.plan.LocalTaskNodeExecutor.execute(LocalTaskNodeExecutor.java:43)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:337)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$InvokeNodeExecutorsAction.execute(DefaultTaskExecutionGraph.java:325)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:318)
        at org.gradle.execution.taskgraph.DefaultTaskExecutionGraph$BuildOperationAwareExecutionAction.execute(DefaultTaskExecutionGraph.java:304)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:134)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker$1.execute(DefaultPlanExecutor.java:129)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.execute(DefaultPlanExecutor.java:202)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.executeNextNode(DefaultPlanExecutor.java:193)
        at org.gradle.execution.plan.DefaultPlanExecutor$ExecutorWorker.run(DefaultPlanExecutor.java:129)
        at org.gradle.internal.concurrent.ExecutorPolicy$CatchAndRecordFailures.onExecute(ExecutorPolicy.java:63)
        at org.gradle.internal.concurrent.ManagedExecutorImpl$1.run(ManagedExecutorImpl.java:46)
        at org.gradle.internal.concurrent.ThreadFactoryImpl$ManagedThreadRunnable.run(ThreadFactoryImpl.java:55)
Caused by: org.gradle.api.internal.tasks.compile.CompilationFailedException: Compilation failed; see the compiler error output for details.
        at org.gradle.api.internal.tasks.compile.JdkJavaCompiler.execute(JdkJavaCompiler.java:52)
        at org.gradle.api.internal.tasks.compile.JdkJavaCompiler.execute(JdkJavaCompiler.java:36)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.delegateAndHandleErrors(NormalizingJavaCompiler.java:100)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:52)
        at org.gradle.api.internal.tasks.compile.NormalizingJavaCompiler.execute(NormalizingJavaCompiler.java:38)
        at org.gradle.api.internal.tasks.compile.AnnotationProcessorDiscoveringCompiler.execute(AnnotationProcessorDiscoveringCompiler.java:51)
        at org.gradle.api.internal.tasks.compile.AnnotationProcessorDiscoveringCompiler.execute(AnnotationProcessorDiscoveringCompiler.java:37)
        at org.gradle.api.internal.tasks.compile.CleaningJavaCompilerSupport.execute(CleaningJavaCompilerSupport.java:39)
        at org.gradle.api.internal.tasks.compile.incremental.IncrementalCompilerFactory$2.execute(IncrementalCompilerFactory.java:110)
        at org.gradle.api.internal.tasks.compile.incremental.IncrementalCompilerFactory$2.execute(IncrementalCompilerFactory.java:106)
        at org.gradle.api.internal.tasks.compile.incremental.IncrementalResultStoringCompiler.execute(IncrementalResultStoringCompiler.java:59)
        at org.gradle.api.internal.tasks.compile.incremental.IncrementalResultStoringCompiler.execute(IncrementalResultStoringCompiler.java:43)
        at org.gradle.api.tasks.compile.JavaCompile.performCompilation(JavaCompile.java:152)
        at org.gradle.api.tasks.compile.JavaCompile.compile(JavaCompile.java:120)
        at org.gradle.internal.reflect.JavaMethod.invoke(JavaMethod.java:73)
        at org.gradle.api.internal.project.taskfactory.IncrementalTaskAction.doExecute(IncrementalTaskAction.java:46)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:41)
        at org.gradle.api.internal.project.taskfactory.StandardTaskAction.execute(StandardTaskAction.java:28)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter$1.run(ExecuteActionsTaskExecuter.java:117)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:301)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor$RunnableBuildOperationWorker.execute(DefaultBuildOperationExecutor.java:293)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.execute(DefaultBuildOperationExecutor.java:175)
        at org.gradle.internal.operations.DefaultBuildOperationExecutor.run(DefaultBuildOperationExecutor.java:91)
        at org.gradle.internal.operations.DelegatingBuildOperationExecutor.run(DelegatingBuildOperationExecutor.java:31)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeAction(ExecuteActionsTaskExecuter.java:106)
        at org.gradle.api.internal.tasks.execution.ExecuteActionsTaskExecuter.executeActions(ExecuteActionsTaskExecuter.java:85)
        ... 35 more


* Get more help at https://help.gradle.org

BUILD FAILED in 0s
2 actionable tasks: 2 executed
thufir@dur:~/NetBeansProjects/com.toscrape.books.selenium$ 

注释工作正常，Selenium可以毫无问题地访问该网页。

Answer 1

原因是注释不适用于局部变量。

此外，留档中注释的实际定义是：

@Retention(value=RUNTIME)
@Target(value={FIELD,TYPE})
public @interface FindBy

因此，注释似乎仍然适用于字段。您可以通过将变量移动到全局级别（类属性）来修复此问题，如下所示：

class WelcomePage {

    @FindBy(partialLinkText = "Books")
    private WebElement books;
    .... // everything else

    void populateCatalogue() {
        // use 'books' here
    }
}