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/*
 * Copyright (C) 2007 Google Inc.
 *
 * Licensed under the Apache License, Version 2.0 (the "License");
 * you may not use this file except in compliance with the License.
 * You may obtain a copy of the License at
 *
 * http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */

package shaded.shaded.com.google.inject;

import shaded.shaded.com.google.inject.binder.AnnotatedBindingBuilder;
import shaded.shaded.com.google.inject.binder.AnnotatedConstantBindingBuilder;
import shaded.shaded.com.google.inject.binder.LinkedBindingBuilder;
import shaded.shaded.com.google.inject.matcher.Matcher;
import shaded.shaded.com.google.inject.spi.Dependency;
import shaded.shaded.com.google.inject.spi.Message;
import shaded.shaded.com.google.inject.spi.ModuleAnnotatedMethodScanner;
import shaded.shaded.com.google.inject.spi.ProvisionListener;
import shaded.shaded.com.google.inject.spi.TypeConverter;
import shaded.shaded.com.google.inject.spi.TypeListener;
import java.lang.annotation.Annotation;
import java.lang.reflect.Method;

/**
 * Collects configuration information (primarily bindings) which will be used to create an
 * {@link Injector}. Guice provides this object to your application's {@link Module} implementors so
 * they may each contribute their own bindings and other registrations.
 *
 * 

The Guice Binding EDSL

* * Guice uses an embedded domain-specific language, or EDSL, to help you create bindings * simply and readably. This approach is great for overall usability, but it does come with a small * cost: it is difficult to learn how to use the Binding EDSL by reading method-level * javadocs. Instead, you should consult the series of examples below. To save space, these * examples omit the opening {@code binder}, just as you will if your module extends {@link * AbstractModule}. * *
 *     bind(ServiceImpl.class);
* * This statement does essentially nothing; it "binds the {@code ServiceImpl} class to itself" and * does not change Guice's default behavior. You may still want to use this if you prefer your * {@link Module} class to serve as an explicit manifest for the services it provides. Also, * in rare cases, Guice may be unable to validate a binding at injector creation time unless it is * given explicitly. * *
 *     bind(Service.class).to(ServiceImpl.class);
* * Specifies that a request for a {@code Service} instance with no binding annotations should be * treated as if it were a request for a {@code ServiceImpl} instance. This overrides the * function of any {@link ImplementedBy @ImplementedBy} or {@link ProvidedBy @ProvidedBy} * annotations found on {@code Service}, since Guice will have already "moved on" to {@code * ServiceImpl} before it reaches the point when it starts looking for these annotations. * *
 *     bind(Service.class).toProvider(ServiceProvider.class);
* * In this example, {@code ServiceProvider} must extend or implement {@code Provider}. This * binding specifies that Guice should resolve an unannotated injection request for {@code Service} * by first resolving an instance of {@code ServiceProvider} in the regular way, then calling {@link * Provider#get get()} on the resulting Provider instance to obtain the {@code Service} instance. * *

The {@link Provider} you use here does not have to be a "factory"; that is, a provider which * always creates each instance it provides. However, this is generally a good practice to * follow. You can then use Guice's concept of {@link Scope scopes} to guide when creation should * happen -- "letting Guice work for you". * *

 *     bind(Service.class).annotatedWith(Red.class).to(ServiceImpl.class);
* * Like the previous example, but only applies to injection requests that use the binding annotation * {@code @Red}. If your module also includes bindings for particular values of the * {@code @Red} annotation (see below), then this binding will serve as a "catch-all" for any values * of {@code @Red} that have no exact match in the bindings. * *
 *     bind(ServiceImpl.class).in(Singleton.class);
 *     // or, alternatively
 *     bind(ServiceImpl.class).in(Scopes.SINGLETON);
* * Either of these statements places the {@code ServiceImpl} class into singleton scope. Guice will * create only one instance of {@code ServiceImpl} and will reuse it for all injection requests of * this type. Note that it is still possible to bind another instance of {@code ServiceImpl} if the * second binding is qualified by an annotation as in the previous example. Guice is not overly * concerned with preventing you from creating multiple instances of your "singletons", only * with enabling your application to share only one instance if that's all you tell Guice you * need. * *

Note: a scope specified in this way overrides any scope that was specified with * an annotation on the {@code ServiceImpl} class. * *

Besides {@link Singleton}/{@link Scopes#SINGLETON}, there are servlet-specific scopes * available in {@code shaded.shaded.com.google.inject.servlet.ServletScopes}, and your Modules can contribute * their own custom scopes for use here as well. * *

 *     bind(new TypeLiteral<PaymentService<CreditCard>>() {})
 *         .to(CreditCardPaymentService.class);
* * This admittedly odd construct is the way to bind a parameterized type. It tells Guice how to * honor an injection request for an element of type {@code PaymentService}. The class * {@code CreditCardPaymentService} must implement the {@code PaymentService} interface. * Guice cannot currently bind or inject a generic type, such as {@code Set}; all type parameters * must be fully specified. * *
 *     bind(Service.class).toInstance(new ServiceImpl());
 *     // or, alternatively
 *     bind(Service.class).toInstance(SomeLegacyRegistry.getService());
* * In this example, your module itself, not Guice, takes responsibility for obtaining a * {@code ServiceImpl} instance, then asks Guice to always use this single instance to fulfill all * {@code Service} injection requests. When the {@link Injector} is created, it will automatically * perform field and method injection for this instance, but any injectable constructor on {@code * ServiceImpl} is simply ignored. Note that using this approach results in "eager loading" behavior * that you can't control. * *
 *     bindConstant().annotatedWith(ServerHost.class).to(args[0]);
* * Sets up a constant binding. Constant injections must always be annotated. When a constant * binding's value is a string, it is eligile for conversion to all primitive types, to {@link * Enum#valueOf(Class, String) all enums}, and to {@link Class#forName class literals}. Conversions * for other types can be configured using {@link #convertToTypes(Matcher, TypeConverter) * convertToTypes()}. * *
 *   {@literal @}Color("red") Color red; // A member variable (field)
 *    . . .
 *     red = MyModule.class.getDeclaredField("red").getAnnotation(Color.class);
 *     bind(Service.class).annotatedWith(red).to(RedService.class);
* * If your binding annotation has parameters you can apply different bindings to different specific * values of your annotation. Getting your hands on the right instance of the annotation is a bit of * a pain -- one approach, shown above, is to apply a prototype annotation to a field in your module * class, so that you can read this annotation instance and give it to Guice. * *
 *     bind(Service.class)
 *         .annotatedWith(Names.named("blue"))
 *         .to(BlueService.class);
* * Differentiating by names is a common enough use case that we provided a standard annotation, * {@link shaded.shaded.com.google.inject.name.Named @Named}. Because of Guice's library support, binding by name * is quite easier than in the arbitrary binding annotation case we just saw. However, remember that * these names will live in a single flat namespace with all the other names used in your * application. * *
 *     Constructor loneCtor = getLoneCtorFromServiceImplViaReflection();
 *     bind(ServiceImpl.class)
 *         .toConstructor(loneCtor);
* * In this example, we directly tell Guice which constructor to use in a concrete class * implementation. It means that we do not need to place {@literal @}Inject on any of the * constructors and that Guice treats the provided constructor as though it were annotated so. It is * useful for cases where you cannot modify existing classes and is a bit simpler than using a * {@link Provider}. * *

The above list of examples is far from exhaustive. If you can think of how the concepts of one * example might coexist with the concepts from another, you can most likely weave the two together. * If the two concepts make no sense with each other, you most likely won't be able to do it. In a * few cases Guice will let something bogus slip by, and will then inform you of the problems at * runtime, as soon as you try to create your Injector. * *

The other methods of Binder such as {@link #bindScope}, {@link #bindInterceptor}, {@link * #install}, {@link #requestStaticInjection}, {@link #addError} and {@link #currentStage} are not * part of the Binding EDSL; you can learn how to use these in the usual way, from the method * documentation. * * @author [email protected] (Bob Lee) * @author [email protected] (Jesse Wilson) * @author [email protected] (Kevin Bourrillion) */ public interface Binder { /*if[AOP]*/ /** * Binds method interceptor[s] to methods matched by class and method matchers. A method is * eligible for interception if: * *

    *
  • Guice created the instance the method is on *
  • Neither the enclosing type nor the method is final *
  • And the method is package-private, protected, or public *
* * @param classMatcher matches classes the interceptor should apply to. For example: {@code * only(Runnable.class)}. * @param methodMatcher matches methods the interceptor should apply to. For example: {@code * annotatedWith(Transactional.class)}. * @param interceptors to bind. The interceptors are called in the order they are given. */ void bindInterceptor( Matcher> classMatcher, Matcher methodMatcher, org.aopalliance.intercept.MethodInterceptor... interceptors); /*end[AOP]*/ /** Binds a scope to an annotation. */ void bindScope(Class annotationType, Scope scope); /** See the EDSL examples at {@link Binder}. */ LinkedBindingBuilder bind(Key key); /** See the EDSL examples at {@link Binder}. */ AnnotatedBindingBuilder bind(TypeLiteral typeLiteral); /** See the EDSL examples at {@link Binder}. */ AnnotatedBindingBuilder bind(Class type); /** See the EDSL examples at {@link Binder}. */ AnnotatedConstantBindingBuilder bindConstant(); /** * Upon successful creation, the {@link Injector} will inject instance fields and methods of the * given object. * * @param type of instance * @param instance for which members will be injected * @since 2.0 */ void requestInjection(TypeLiteral type, T instance); /** * Upon successful creation, the {@link Injector} will inject instance fields and methods of the * given object. * * @param instance for which members will be injected * @since 2.0 */ void requestInjection(Object instance); /** * Upon successful creation, the {@link Injector} will inject static fields and methods in the * given classes. * * @param types for which static members will be injected */ void requestStaticInjection(Class... types); /** Uses the given module to configure more bindings. */ void install(Module module); /** Gets the current stage. */ Stage currentStage(); /** * Records an error message which will be presented to the user at a later time. Unlike throwing * an exception, this enable us to continue configuring the Injector and discover more errors. * Uses {@link String#format(String, Object[])} to insert the arguments into the message. */ void addError(String message, Object... arguments); /** * Records an exception, the full details of which will be logged, and the message of which will * be presented to the user at a later time. If your Module calls something that you worry may * fail, you should catch the exception and pass it into this. */ void addError(Throwable t); /** * Records an error message to be presented to the user at a later time. * * @since 2.0 */ void addError(Message message); /** * Returns the provider used to obtain instances for the given injection key. The returned * provider will not be valid until the {@link Injector} has been created. The provider will throw * an {@code IllegalStateException} if you try to use it beforehand. * * @since 2.0 */ Provider getProvider(Key key); /** * Returns the provider used to obtain instances for the given injection key. The returned * provider will be attached to the injection point and will follow the nullability specified in * the dependency. Additionally, the returned provider will not be valid until the {@link * Injector} has been created. The provider will throw an {@code IllegalStateException} if you try * to use it beforehand. * * @since 4.0 */ Provider getProvider(Dependency dependency); /** * Returns the provider used to obtain instances for the given injection type. The returned * provider will not be valid until the {@link Injector} has been created. The provider will throw * an {@code IllegalStateException} if you try to use it beforehand. * * @since 2.0 */ Provider getProvider(Class type); /** * Returns the members injector used to inject dependencies into methods and fields on instances * of the given type {@code T}. The returned members injector will not be valid until the main * {@link Injector} has been created. The members injector will throw an {@code * IllegalStateException} if you try to use it beforehand. * * @param typeLiteral type to get members injector for * @since 2.0 */ MembersInjector getMembersInjector(TypeLiteral typeLiteral); /** * Returns the members injector used to inject dependencies into methods and fields on instances * of the given type {@code T}. The returned members injector will not be valid until the main * {@link Injector} has been created. The members injector will throw an {@code * IllegalStateException} if you try to use it beforehand. * * @param type type to get members injector for * @since 2.0 */ MembersInjector getMembersInjector(Class type); /** * Binds a type converter. The injector will use the given converter to convert string constants * to matching types as needed. * * @param typeMatcher matches types the converter can handle * @param converter converts values * @since 2.0 */ void convertToTypes(Matcher> typeMatcher, TypeConverter converter); /** * Registers a listener for injectable types. Guice will notify the listener when it encounters * injectable types matched by the given type matcher. * * @param typeMatcher that matches injectable types the listener should be notified of * @param listener for injectable types matched by typeMatcher * @since 2.0 */ void bindListener(Matcher> typeMatcher, TypeListener listener); /** * Registers listeners for provisioned objects. Guice will notify the listeners just before and * after the object is provisioned. Provisioned objects that are also injectable (everything * except objects provided through Providers) can also be notified through TypeListeners * registered in {@link #bindListener}. * * @param bindingMatcher that matches bindings of provisioned objects the listener should be * notified of * @param listeners for provisioned objects matched by bindingMatcher * @since 4.0 */ void bindListener(Matcher> bindingMatcher, ProvisionListener... listeners); /** * Returns a binder that uses {@code source} as the reference location for configuration errors. * This is typically a {@link StackTraceElement} for {@code .java} source but it could any binding * source, such as the path to a {@code .properties} file. * * @param source any object representing the source location and has a concise {@link * Object#toString() toString()} value * @return a binder that shares its configuration with this binder * @since 2.0 */ Binder withSource(Object source); /** * Returns a binder that skips {@code classesToSkip} when identify the calling code. The caller's * {@link StackTraceElement} is used to locate the source of configuration errors. * * @param classesToSkip library classes that create bindings on behalf of their clients. * @return a binder that shares its configuration with this binder. * @since 2.0 */ Binder skipSources(Class... classesToSkip); /** * Creates a new private child environment for bindings and other configuration. The returned * binder can be used to add and configuration information in this environment. See {@link * PrivateModule} for details. * * @return a binder that inherits configuration from this binder. Only exposed configuration on * the returned binder will be visible to this binder. * @since 2.0 */ PrivateBinder newPrivateBinder(); /** * Instructs the Injector that bindings must be listed in a Module in order to be injected. * Classes that are not explicitly bound in a module cannot be injected. Bindings created through * a linked binding (bind(Foo.class).to(FooImpl.class)) are allowed, but the implicit * binding (FooImpl) cannot be directly injected unless it is also explicitly bound ( * bind(FooImpl.class)). * *

Tools can still retrieve bindings for implicit bindings (bindings created through a linked * binding) if explicit bindings are required, however {@link Binding#getProvider} will fail. * *

By default, explicit bindings are not required. * *

If a parent injector requires explicit bindings, then all child injectors (and private * modules within that injector) also require explicit bindings. If a parent does not require * explicit bindings, a child injector or private module may optionally declare itself as * requiring explicit bindings. If it does, the behavior is limited only to that child or any * grandchildren. No siblings of the child will require explicit bindings. * *

In the absence of an explicit binding for the target, linked bindings in child injectors * create a binding for the target in the parent. Since this behavior can be surprising, it causes * an error instead if explicit bindings are required. To avoid this error, add an explicit * binding for the target, either in the child or the parent. * * @since 3.0 */ void requireExplicitBindings(); /** * Prevents Guice from injecting dependencies that form a cycle, unless broken by a {@link * Provider}. By default, circular dependencies are not disabled. * *

If a parent injector disables circular dependencies, then all child injectors (and private * modules within that injector) also disable circular dependencies. If a parent does not disable * circular dependencies, a child injector or private module may optionally declare itself as * disabling circular dependencies. If it does, the behavior is limited only to that child or any * grandchildren. No siblings of the child will disable circular dependencies. * * @since 3.0 */ void disableCircularProxies(); /** * Requires that a {@literal @}{@link Inject} annotation exists on a constructor in order for * Guice to consider it an eligible injectable class. By default, Guice will inject classes that * have a no-args constructor if no {@literal @}{@link Inject} annotation exists on any * constructor. * *

If the class is bound using {@link LinkedBindingBuilder#toConstructor}, Guice will still * inject that constructor regardless of annotations. * * @since 4.0 */ void requireAtInjectOnConstructors(); /** * Requires that Guice finds an exactly matching binding annotation. This disables the error-prone * feature in Guice where it can substitute a binding for {@literal @}Named Foo when * attempting to inject {@literal @}Named("foo") Foo. * * @since 4.0 */ void requireExactBindingAnnotations(); /** * Adds a scanner that will look in all installed modules for annotations the scanner can parse, * and binds them like {@literal @}Provides methods. Scanners apply to all modules installed in * the injector. Scanners installed in child injectors or private modules do not impact modules in * siblings or parents, however scanners installed in parents do apply to all child injectors and * private modules. * * @since 4.0 */ void scanModulesForAnnotatedMethods(ModuleAnnotatedMethodScanner scanner); }





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