用Guice的方法createInjector找不到符号

Question

我的项目得到一个奇怪的错误，我在POM.xml中添加了Guice到我的依赖项，一切看起来都很好IDE给出了一个全部的建议，即使我在编写代码来启动Injector时它也提示我方法I想要使用，但后来它标记为红色，说它无法找到，我从来没有经历过这样的事情。也许我忘了什么。谁能帮我？

我的项目是maven JavaFX桌面应用程序。

这是错误的输出

/Library/Java/JavaVirtualMachines/jdk1.8.0_162.jdk/Contents/Home/bin/java -Dmaven.multiModuleProjectDirectory=/Users/ochamo/Documents/Proyectos/apde-alumnus/APDEAlumnus "-Dmaven.home=/Applications/IntelliJ IDEA.app/Contents/plugins/maven/lib/maven3" "-Dclassworlds.conf=/Applications/IntelliJ IDEA.app/Contents/plugins/maven/lib/maven3/bin/m2.conf" "-javaagent:/Applications/IntelliJ IDEA.app/Contents/lib/idea_rt.jar=52291:/Applications/IntelliJ IDEA.app/Contents/bin" -Dfile.encoding=UTF-8 -classpath "/Applications/IntelliJ IDEA.app/Contents/plugins/maven/lib/maven3/boot/plexus-classworlds-2.5.2.jar" org.codehaus.classworlds.Launcher -Didea.version2019.1 com.zenjava:javafx-maven-plugin:8.8.3:jar
[INFO] Scanning for projects...
[INFO]                                                                         
[INFO] ------------------------------------------------------------------------
[INFO] Building APDE-Alumnus 1.0
[INFO] ------------------------------------------------------------------------
[INFO] 
[INFO] >>> javafx-maven-plugin:8.8.3:jar (default-cli) > [jfxjar]package @ APDE-Alumnus >>>
[INFO] 
[INFO] --- maven-resources-plugin:2.6:resources (default-resources) @ APDE-Alumnus ---
[INFO] Using 'UTF-8' encoding to copy filtered resources.
[INFO] Copying 10 resources
[INFO] 
[INFO] --- maven-compiler-plugin:3.1:compile (default-compile) @ APDE-Alumnus ---
[INFO] Changes detected - recompiling the module!
[INFO] Compiling 13 source files to /Users/ochamo/Documents/Proyectos/apde-alumnus/APDEAlumnus/target/classes
[INFO] -------------------------------------------------------------
[ERROR] COMPILATION ERROR : 
[INFO] -------------------------------------------------------------
[ERROR] /Users/ochamo/Documents/Proyectos/apde-alumnus/APDEAlumnus/src/main/java/edu/apde/alumnus/main/Main.java:[22,47] cannot find symbol
  symbol:   class createInjector
  location: class com.google.inject.Guice
[INFO] 1 error
[INFO] -------------------------------------------------------------
[INFO] ------------------------------------------------------------------------
[INFO] BUILD FAILURE
[INFO] ------------------------------------------------------------------------
[INFO] Total time: 1.584 s
[INFO] Finished at: 2019-04-03T12:10:32-06:00
[INFO] Final Memory: 21M/309M
[INFO] ------------------------------------------------------------------------

这是pom.xml中的Guice依赖项

<dependency>
   <groupId>com.google.inject</groupId>
   <artifactId>guice</artifactId>
   <version>4.2.1</version>
</dependency>

我用来引导我的主类的代码

public class Main extends Application {
    public static void main(String[] args) {
        launch(args);
    }
    @Override
    public void start(Stage primaryStage) throws Exception {

       try {
           final Injector injector = new Guice.createInjector(new MainModule()); // this is the source of the error It cannot find createInjector.

           FXMLLoader fxmlLoader = new FXMLLoader();
           fxmlLoader.setLocation(Main.class.getResource("/fxml/main/main-view.fxml"));
           System.out.printf("location: " + fxmlLoader.getLocation());
           GridPane root = fxmlLoader.load();
           Scene scene = new Scene(root);

           primaryStage.setScene(scene);
           primaryStage.setTitle("Login");
           primaryStage.show();
       } catch (IllegalStateException ex) {
           ex.printStackTrace();
       }
    }
}

Answer 1

createInjector方法是一种静态方法（参见Javadocs）......

public static Injector createInjector(Module... modules) {
    return createInjector((Iterable)Arrays.asList(modules));
}    

当你试图像这样调用它时......

new Guice().createInjector(...)

...您正在尝试调用实例方法，但由于createInjector类中没有名为Guice的实例方法，因此无法编译。

相反，你应该像这样调用它：

Guice.createInjector(...)

要清楚;而不是调用new Guice()你只需要在Guice上调用。

背景：

• 必须在其类的实例上调用实例方法;要调用实例方法，必须创建定义方法的类的实例。例如：new Foo().doIt()
• 调用静态方法而不创建其类的实例;要调用静态方法，只需通过其类名引用它。例如：Foo.doIt()