Guice 学习（五）多接口的实现（ Many Interface Implementation）

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1、接口

/* * Creation : 2015年6月30日 */package com.guice.InterfaceManyImpl;public interface Service {    public void execute();}

2、两个实现类

package com.guice.InterfaceManyImpl;public class OneService implements Service {    @Override    public void execute() {        System.out.println("Hello!  I'M Service 1!");    }}

package com.guice.InterfaceManyImpl;public class TwoService implements Service {    @Override    public void execute() {        System.out.println("Hello!  I'M Service 2!");    }}

3、两个注解类

package com.guice.InterfaceManyImpl;import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;import com.google.inject.BindingAnnotation;@Retention(RetentionPolicy.RUNTIME)@Target({ ElementType.FIELD, ElementType.PARAMETER })@BindingAnnotationpublic @interface One { }

package com.guice.InterfaceManyImpl;import java.lang.annotation.ElementType;import java.lang.annotation.Retention;import java.lang.annotation.RetentionPolicy;import java.lang.annotation.Target;import com.google.inject.BindingAnnotation;@Retention(RetentionPolicy.RUNTIME)@Target({ ElementType.FIELD, ElementType.PARAMETER })@BindingAnnotationpublic @interface Two {}

4、多接口实现测试类

package com.guice.InterfaceManyImpl;import com.google.inject.Binder;import com.google.inject.Guice;import com.google.inject.Inject;import com.google.inject.Module;/* * 接口的多实现： * 此类的结构是注入了两个service服务，注解One和OneService关联，第二个和它一样 */public class InterfaceManyImpl {    @Inject    @One    private Service oneService;    @Inject    @Two    private Service twoService;    public static void main(String[] args) {        InterfaceManyImpl instance = Guice.createInjector(new Module() {            @Override            public void configure(Binder binder) {                //让注解类和实现类绑定                binder.bind(Service.class).annotatedWith(One.class).to(OneService.class);                binder.bind(Service.class).annotatedWith(Two.class).to(TwoService.class);            }        }).getInstance(InterfaceManyImpl.class);        instance.oneService.execute();        instance.twoService.execute();    }}

5、无注解的多接口实现测试类

package com.guice.InterfaceManyImpl;import com.google.inject.Binder;import com.google.inject.Guice;import com.google.inject.Inject;import com.google.inject.Module;import com.google.inject.name.Named;import com.google.inject.name.Names;/** * TODO : 程序员比较懒，不想写注解来区分多个服务则可以使用Google提供的一个叫Names的模板来生成注解 * @author E468380 */public class NoAnnotationMultiInterfaceServiceDemo {    @Inject    @Named("One")    private static Service oneService;    @Inject    @Named("Two")    private static Service twoService;    public static void main(String[] args) {        Guice.createInjector(new Module() {            @Override            public void configure(Binder binder) {                // 这里不同                binder.bind(Service.class).annotatedWith(Names.named("One")).to(OneService.class);                binder.bind(Service.class).annotatedWith(Names.named("Two")).to(TwoService.class);                binder.requestStaticInjection(NoAnnotationMultiInterfaceServiceDemo.class);            }        });        NoAnnotationMultiInterfaceServiceDemo.oneService.execute();        NoAnnotationMultiInterfaceServiceDemo.twoService.execute();    }}

6、静态的多接口实现测试类

问题（1）静态注入多个服务怎么写？

package com.guice.InterfaceManyImpl;import com.google.inject.Binder;import com.google.inject.Guice;import com.google.inject.Inject;import com.google.inject.Module;/** * TODO :也可以静态注入多个服务 *  * @author E468380 */public class StaticMultiInterfaceServiceDemo {    @Inject    @One    private static Service oneService;    @Inject    @One    private static Service twoService;    public static void main(String[] args) {        Guice.createInjector(new Module() {            @Override            public void configure(Binder binder) {                binder.bind(Service.class).annotatedWith(One.class).to(OneService.class);                binder.bind(Service.class).annotatedWith(Two.class).to(TwoService.class);                binder.requestStaticInjection(StaticMultiInterfaceServiceDemo.class);            }        });        StaticMultiInterfaceServiceDemo.oneService.execute();        StaticMultiInterfaceServiceDemo.twoService.execute();    }}// 如果不小心一个属性绑定了多个接口怎么办？ --》不可以绑定多个服务。

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