在链接绑定中,Guice将类型映射到其实现.在下面的示例中,我们已经将SpellChecker接口与其实现SpellCheckerImpl映射.
bind(SpellChecker.class).to(SpellCheckerImpl.class);
我们还可以将具体类映射到其子类.请参阅下面的示例 :
bind(SpellCheckerImpl.class).to(WinWordSpellCheckerImpl.class);
这里我们链接了绑定.让我们看一下完整示例中的结果.
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; 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(SpellChecker.class).to(SpellCheckerImpl.class); bind(SpellCheckerImpl.class).to(WinWordSpellCheckerImpl.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 WinWordSpellCheckerImpl extends SpellCheckerImpl { @Override public void checkSpelling() { System.out.println("Inside WinWordSpellCheckerImpl.checkSpelling." ); } }
编译并运行文件,你会看到以下输出.
Inside WinWordSpellCheckerImpl.checkSpelling.