@ImplementatedBy annotation

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2023-12-01

@ImplementatedBy注释告诉guice有关实现类。在这种情况下，绑定模块不需要绑定。看看例子 -

例子 (Example)

创建一个名为GuiceTester的java类。

GuiceTester.java

import com.google.inject.AbstractModule;
import com.google.inject.Guice;
import com.google.inject.ImplementedBy;
import com.google.inject.Inject;
import com.google.inject.Injector;
import com.google.inject.name.Named;
import com.google.inject.name.Names;
public class GuiceTester {
   public static void main(String[] args) {
      Injector injector = Guice.createInjector(new TextEditorModule());
      TextEditor editor = injector.getInstance(TextEditor.class);
      editor.makeSpellCheck();
   } 
}
class TextEditor {
   private SpellChecker spellChecker;
   @Inject
   public TextEditor( SpellChecker spellChecker) {
      this.spellChecker = spellChecker;
   }
   public void makeSpellCheck() {
      spellChecker.checkSpelling();
   } 
}
//Binding Module
class TextEditorModule extends AbstractModule {
   @Override
   protected void configure() { 
      bind(String.class)
         .annotatedWith(Names.named("JDBC"))
         .toInstance("jdbc:mysql://localhost:5326/emp");
   } 
}
@ImplementedBy(SpellCheckerImpl.class)
interface SpellChecker {
   public void checkSpelling();
}
//spell checker implementation
class SpellCheckerImpl implements SpellChecker {
   @Inject @Named("JDBC")
   private String dbUrl;
   public SpellCheckerImpl(){}
   @Override
   public void checkSpelling() { 
      System.out.println("Inside checkSpelling." );
      System.out.println(dbUrl); 
   }
}

输出 (Output)

编译并运行该文件，您将看到以下输出。

Inside checkSpelling.
jdbc:mysql://localhost:5326/emp