Guice还提供了另一种在不创建自定义注释的情况下映射绑定的方法.它允许使用@Named注释.
bind(SpellChecker.class).annotatedWith(Names.named("OpenOffice")).to(OpenOfficeWordSpellCheckerImpl.class);
@Inject public TextEditor(@Named("OpenOffice") SpellChecker spellChecker) { this.spellChecker = spellChecker; }
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.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(@Named("OpenOffice") SpellChecker spellChecker) { this.spellChecker = spellChecker; } public void makeSpellCheck() { spellChecker.checkSpelling(); } } //Binding Module class TextEditorModule extends AbstractModule { @Override protected void configure() { bind(SpellChecker.class).annotatedWith(Names.named("OpenOffice")) .to(OpenOfficeWordSpellCheckerImpl.class); } } //spell checker interface interface SpellChecker { public void checkSpelling(); } //spell checker implementation class SpellCheckerImpl implements SpellChecker { @Override public void checkSpelling() { System.out.println("Inside checkSpelling." ); } } //subclass of SpellCheckerImpl class OpenOfficeWordSpellCheckerImpl extends SpellCheckerImpl { @Override public void checkSpelling() { System.out.println("Inside OpenOfficeWordSpellCheckerImpl.checkSpelling." ); } }
编译并运行文件,你会看到以下输出.
Inside OpenOfficeWordSpellCheckerImpl.checkSpelling..