test/com/google/inject/ScopesTest.java - platform/external/guice - Git at Google

 /**
  * Copyright (C) 2006 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 com.google.inject;

 import static com.google.inject.Asserts.assertContains;
 import com.google.inject.internal.Maps;
 import java.io.IOException;
 import java.lang.annotation.ElementType;
 import java.lang.annotation.Retention;
 import static java.lang.annotation.RetentionPolicy.RUNTIME;
 import java.lang.annotation.Target;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import junit.framework.TestCase;

 /**
  * @author crazybob@google.com (Bob Lee)
  */
 public class ScopesTest extends TestCase {

   private final AbstractModule singletonsModule = new AbstractModule() {
     protected void configure() {
       bind(BoundAsSingleton.class).in(Scopes.SINGLETON);
       bind(AnnotatedSingleton.class);
       bind(EagerSingleton.class).asEagerSingleton();
       bind(LinkedSingleton.class).to(RealLinkedSingleton.class);
       bind(DependsOnJustInTimeSingleton.class);
       bind(NotASingleton.class);
       bind(ImplementedBySingleton.class).in(Scopes.SINGLETON);
       bind(ProvidedBySingleton.class).in(Scopes.SINGLETON);
     }
   };

   @Override protected void setUp() throws Exception {
     AnnotatedSingleton.nextInstanceId = 0;
     BoundAsSingleton.nextInstanceId = 0;
     EagerSingleton.nextInstanceId = 0;
     RealLinkedSingleton.nextInstanceId = 0;
     JustInTimeSingleton.nextInstanceId = 0;
     NotASingleton.nextInstanceId = 0;
     Implementation.nextInstanceId = 0;
     ProvidedBySingleton.nextInstanceId = 0;
   }

   public void testSingletons() {
     Injector injector = Guice.createInjector(singletonsModule);

     assertSame(
         injector.getInstance(BoundAsSingleton.class),
         injector.getInstance(BoundAsSingleton.class));

     assertSame(
         injector.getInstance(AnnotatedSingleton.class),
         injector.getInstance(AnnotatedSingleton.class));

     assertSame(
         injector.getInstance(EagerSingleton.class),
         injector.getInstance(EagerSingleton.class));

     assertSame(
         injector.getInstance(LinkedSingleton.class),
         injector.getInstance(LinkedSingleton.class));

     assertSame(
         injector.getInstance(JustInTimeSingleton.class),
         injector.getInstance(JustInTimeSingleton.class));

     assertNotSame(
         injector.getInstance(NotASingleton.class),
         injector.getInstance(NotASingleton.class));

     assertSame(
         injector.getInstance(ImplementedBySingleton.class),
         injector.getInstance(ImplementedBySingleton.class));

     assertSame(
         injector.getInstance(ProvidedBySingleton.class),
         injector.getInstance(ProvidedBySingleton.class));
   }

   public void testJustInTimeAnnotatedSingleton() {
     Injector injector = Guice.createInjector();

     assertSame(
         injector.getInstance(AnnotatedSingleton.class),
         injector.getInstance(AnnotatedSingleton.class));
   }

   public void testSingletonIsPerInjector() {
     assertNotSame(
         Guice.createInjector().getInstance(AnnotatedSingleton.class),
         Guice.createInjector().getInstance(AnnotatedSingleton.class));
   }

   public void testOverriddingAnnotation() {
     Injector injector = Guice.createInjector(new AbstractModule() {
       protected void configure() {
         bind(AnnotatedSingleton.class).in(Scopes.NO_SCOPE);
       }
     });

     assertNotSame(
         injector.getInstance(AnnotatedSingleton.class),
         injector.getInstance(AnnotatedSingleton.class));
   }

   public void testScopingAnnotationsOnAbstractTypeViaBind() {
     try {
       Guice.createInjector(new AbstractModule() {
         protected void configure() {
           bind(A.class).to(AImpl.class);
         }
       });
       fail();
     } catch (CreationException expected) {
       assertContains(expected.getMessage(),
           A.class.getName() + " is annotated with " + Singleton.class.getName(),
           "but scope annotations are not supported for abstract types.",
           "at " + A.class.getName() + ".class(ScopesTest.java:");
     }
   }

   @Singleton
   interface A {}
   static class AImpl implements A {}

   public void testScopingAnnotationsOnAbstractTypeViaImplementedBy() {
     try {
       Guice.createInjector().getInstance(D.class);
       fail();
     } catch (ConfigurationException expected) {
       assertContains(expected.getMessage(),
           D.class.getName() + " is annotated with " + Singleton.class.getName(),
           "but scope annotations are not supported for abstract types.",
           "at " + D.class.getName() + ".class(ScopesTest.java:");
     }
   }

   @Singleton @ImplementedBy(DImpl.class)
   interface D {}
   static class DImpl implements D {}

   public void testScopingAnnotationsOnAbstractTypeViaProvidedBy() {
     try {
       Guice.createInjector().getInstance(E.class);
       fail();
     } catch (ConfigurationException expected) {
       assertContains(expected.getMessage(),
           E.class.getName() + " is annotated with " + Singleton.class.getName(),
           "but scope annotations are not supported for abstract types.",
           "at " + E.class.getName() + ".class(ScopesTest.java:");
     }
   }

   @Singleton @ProvidedBy(EProvider.class)
   interface E {}
   static class EProvider implements Provider<E> {
     public E get() {
       return null;
     }
   }

   public void testScopeUsedButNotBound() {
     try {
       Guice.createInjector(new AbstractModule() {
         protected void configure() {
           bind(B.class).in(CustomScoped.class);
           bind(C.class);
         }
       });
       fail();
     } catch (CreationException expected) {
       assertContains(expected.getMessage(),
           "1) No scope is bound to " + CustomScoped.class.getName(),
           "at " + getClass().getName(), ".configure(ScopesTest.java:",
           "2) No scope is bound to " + CustomScoped.class.getName(),
           "at " + C.class.getName() + ".class");
     }
   }

   static class B {}

   @CustomScoped
   static class C {}

   public void testSingletonsInProductionStage() {
     Guice.createInjector(Stage.PRODUCTION, singletonsModule);

     assertEquals(1, AnnotatedSingleton.nextInstanceId);
     assertEquals(1, BoundAsSingleton.nextInstanceId);
     assertEquals(1, EagerSingleton.nextInstanceId);
     assertEquals(1, RealLinkedSingleton.nextInstanceId);
     assertEquals(1, JustInTimeSingleton.nextInstanceId);
     assertEquals(0, NotASingleton.nextInstanceId);
   }

   public void testSingletonsInDevelopmentStage() {
     Guice.createInjector(Stage.DEVELOPMENT, singletonsModule);

     assertEquals(0, AnnotatedSingleton.nextInstanceId);
     assertEquals(0, BoundAsSingleton.nextInstanceId);
     assertEquals(1, EagerSingleton.nextInstanceId);
     assertEquals(0, RealLinkedSingleton.nextInstanceId);
     assertEquals(0, JustInTimeSingleton.nextInstanceId);
     assertEquals(0, NotASingleton.nextInstanceId);
   }

   public void testSingletonScopeIsNotSerializable() throws IOException {
     Asserts.assertNotSerializable(Scopes.SINGLETON);
   }

   public void testNoScopeIsNotSerializable() throws IOException {
     Asserts.assertNotSerializable(Scopes.NO_SCOPE);
   }

   public void testUnscopedProviderWorksOutsideOfRequestedScope() {
     final RememberProviderScope scope = new RememberProviderScope();

     Injector injector = Guice.createInjector(new AbstractModule() {
       protected void configure() {
         bindScope(CustomScoped.class, scope);
         bind(List.class).to(ArrayList.class).in(CustomScoped.class);
       }
     });

     injector.getInstance(List.class);
     Provider<?> listProvider = scope.providers.get(Key.get(List.class));

     // this line fails with a NullPointerException because the Providers
     // passed to Scope.scope() don't work outside of the scope() method.
     assertTrue(listProvider.get() instanceof ArrayList);
   }

   public void testScopeAnnotationWithoutRuntimeRetention() {
     try {
       Guice.createInjector(new AbstractModule() {
         protected void configure() {
           bindScope(NotRuntimeRetainedScoped.class, Scopes.NO_SCOPE);
         }
       });
       fail();
     } catch (CreationException expected) {
       assertContains(expected.getMessage(),
           "1) Please annotate with @Retention(RUNTIME).",
           "at " + NotRuntimeRetainedScoped.class.getName() + ".class(ScopesTest.java:");
     }
   }

   public void testBindScopeToAnnotationWithoutScopeAnnotation() {
     try {
       Guice.createInjector(new AbstractModule() {
         protected void configure() {
           bindScope(Deprecated.class, Scopes.NO_SCOPE);
         }
       });
       fail();
     } catch (CreationException expected) {
       assertContains(expected.getMessage(),
           "1) Please annotate with @ScopeAnnotation.",
           "at " + Deprecated.class.getName() + ".class(");
     }
   }

   public void testBindScopeTooManyTimes() {
     try {
       Guice.createInjector(new AbstractModule() {
         protected void configure() {
           bindScope(CustomScoped.class, Scopes.NO_SCOPE);
           bindScope(CustomScoped.class, Scopes.SINGLETON);
         }
       });
       fail();
     } catch (CreationException expected) {
       assertContains(expected.getMessage(),
           "1) Scope Scopes.NO_SCOPE is already bound to " + CustomScoped.class.getName(),
           "Cannot bind Scopes.SINGLETON.",
           "at " + ScopesTest.class.getName(), ".configure(ScopesTest.java:");
     }
   }

   public void testDuplicateScopeAnnotations() {
     Injector injector = Guice.createInjector(new AbstractModule() {
       protected void configure() {
         bindScope(CustomScoped.class, Scopes.NO_SCOPE);
       }
     });

     try {
       injector.getInstance(SingletonAndCustomScoped.class);
       fail();
     } catch (ConfigurationException expected) {
       assertContains(expected.getMessage(),
           "1) More than one scope annotation was found: ",
           "while locating " + SingletonAndCustomScoped.class.getName());
     }
   }

   public void testNullScopedAsASingleton() {
     Provider<String> unscoped = new Provider<String>() {
       final Iterator<String> values = Arrays.asList(null, "A").iterator();
       public String get() {
         return values.next();
       }
     };

     Provider<String> scoped = Scopes.SINGLETON.scope(Key.get(String.class), unscoped);
     assertNull(scoped.get());
     assertNull(scoped.get());
     assertNull(scoped.get());
   }

   class RememberProviderScope implements Scope {
     final Map<Key<?>, Provider<?>> providers = Maps.newHashMap();
     public <T> Provider<T> scope(Key<T> key, Provider<T> unscoped) {
       providers.put(key, unscoped);
       return unscoped;
     }
   }

   public void testSingletonAnnotationOnParameterizedType() {
     Injector injector = Guice.createInjector();
     assertSame(injector.getInstance(new Key<Injected<String>>() {}),
         injector.getInstance(new Key<Injected<String>>() {}));
     assertSame(injector.getInstance(new Key<In<Integer>>() {}),
         injector.getInstance(new Key<In<Short>>() {}));
   }

   @ImplementedBy(Injected.class) public interface In<T> {}
   @Singleton public static class Injected<T>  implements In<T> {}

   @Target({ ElementType.TYPE, ElementType.METHOD })
   @Retention(RUNTIME)
   @ScopeAnnotation
   public @interface CustomScoped {}

   @Target({ ElementType.TYPE, ElementType.METHOD })
   @ScopeAnnotation
   public @interface NotRuntimeRetainedScoped {}

   @Singleton
   static class AnnotatedSingleton {
     static int nextInstanceId;
     final int instanceId = nextInstanceId++;
   }

   static class BoundAsSingleton {
     static int nextInstanceId;
     final int instanceId = nextInstanceId++;
   }

   static class EagerSingleton {
     static int nextInstanceId;
     final int instanceId = nextInstanceId++;
   }

   interface LinkedSingleton {}

   @Singleton
   static class RealLinkedSingleton implements LinkedSingleton {
     static int nextInstanceId;
     final int instanceId = nextInstanceId++;
   }

   static class DependsOnJustInTimeSingleton {
     @Inject JustInTimeSingleton justInTimeSingleton;
   }

   @Singleton
   static class JustInTimeSingleton {
     static int nextInstanceId;
     final int instanceId = nextInstanceId++;
   }

   static class NotASingleton {
     static int nextInstanceId;
     final int instanceId = nextInstanceId++;
   }

   @Singleton @CustomScoped
   static class SingletonAndCustomScoped {}

   @ImplementedBy(Implementation.class)
   static interface ImplementedBySingleton {}

   @ProvidedBy(ImplementationProvider.class)
   static class ProvidedBySingleton {
     static int nextInstanceId;
     final int instanceId = nextInstanceId++;
   }

   static class Implementation implements ImplementedBySingleton {
     static int nextInstanceId;
     final int instanceId = nextInstanceId++;
   }

   static class ImplementationProvider implements Provider<ProvidedBySingleton> {
     public ProvidedBySingleton get() {
       return new ProvidedBySingleton();
     }
   }

   public void testScopeThatGetsAnUnrelatedObject() {
     Injector injector = Guice.createInjector(new AbstractModule() {
       protected void configure() {
         bind(B.class);
         bind(C.class);
         ProviderGetScope providerGetScope = new ProviderGetScope();
         requestInjection(providerGetScope);
         bindScope(CustomScoped.class, providerGetScope);
       }
     });

     injector.getInstance(C.class);
   }

   class ProviderGetScope implements Scope {
     @Inject Provider<B> bProvider;

     public <T> Provider<T> scope(Key<T> key, final Provider<T> unscoped) {
       return new Provider<T>() {
         public T get() {
           bProvider.get();
           return unscoped.get();
         }
       };
     }
   }
 }
	/**
	* Copyright (C) 2006 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 com.google.inject;

	import static com.google.inject.Asserts.assertContains;
	import com.google.inject.internal.Maps;
	import java.io.IOException;
	import java.lang.annotation.ElementType;
	import java.lang.annotation.Retention;
	import static java.lang.annotation.RetentionPolicy.RUNTIME;
	import java.lang.annotation.Target;
	import java.util.ArrayList;
	import java.util.Arrays;
	import java.util.Iterator;
	import java.util.List;
	import java.util.Map;
	import junit.framework.TestCase;

	/**
	* @author crazybob@google.com (Bob Lee)
	*/
	public class ScopesTest extends TestCase {

	private final AbstractModule singletonsModule = new AbstractModule() {
	protected void configure() {
	bind(BoundAsSingleton.class).in(Scopes.SINGLETON);
	bind(AnnotatedSingleton.class);
	bind(EagerSingleton.class).asEagerSingleton();
	bind(LinkedSingleton.class).to(RealLinkedSingleton.class);
	bind(DependsOnJustInTimeSingleton.class);
	bind(NotASingleton.class);
	bind(ImplementedBySingleton.class).in(Scopes.SINGLETON);
	bind(ProvidedBySingleton.class).in(Scopes.SINGLETON);
	}
	};

	@Override protected void setUp() throws Exception {
	AnnotatedSingleton.nextInstanceId = 0;
	BoundAsSingleton.nextInstanceId = 0;
	EagerSingleton.nextInstanceId = 0;
	RealLinkedSingleton.nextInstanceId = 0;
	JustInTimeSingleton.nextInstanceId = 0;
	NotASingleton.nextInstanceId = 0;
	Implementation.nextInstanceId = 0;
	ProvidedBySingleton.nextInstanceId = 0;
	}

	public void testSingletons() {
	Injector injector = Guice.createInjector(singletonsModule);

	assertSame(
	injector.getInstance(BoundAsSingleton.class),
	injector.getInstance(BoundAsSingleton.class));

	assertSame(
	injector.getInstance(AnnotatedSingleton.class),
	injector.getInstance(AnnotatedSingleton.class));

	assertSame(
	injector.getInstance(EagerSingleton.class),
	injector.getInstance(EagerSingleton.class));

	assertSame(
	injector.getInstance(LinkedSingleton.class),
	injector.getInstance(LinkedSingleton.class));

	assertSame(
	injector.getInstance(JustInTimeSingleton.class),
	injector.getInstance(JustInTimeSingleton.class));

	assertNotSame(
	injector.getInstance(NotASingleton.class),
	injector.getInstance(NotASingleton.class));

	assertSame(
	injector.getInstance(ImplementedBySingleton.class),
	injector.getInstance(ImplementedBySingleton.class));

	assertSame(
	injector.getInstance(ProvidedBySingleton.class),
	injector.getInstance(ProvidedBySingleton.class));
	}

	public void testJustInTimeAnnotatedSingleton() {
	Injector injector = Guice.createInjector();

	assertSame(
	injector.getInstance(AnnotatedSingleton.class),
	injector.getInstance(AnnotatedSingleton.class));
	}

	public void testSingletonIsPerInjector() {
	assertNotSame(
	Guice.createInjector().getInstance(AnnotatedSingleton.class),
	Guice.createInjector().getInstance(AnnotatedSingleton.class));
	}

	public void testOverriddingAnnotation() {
	Injector injector = Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bind(AnnotatedSingleton.class).in(Scopes.NO_SCOPE);
	}
	});

	assertNotSame(
	injector.getInstance(AnnotatedSingleton.class),
	injector.getInstance(AnnotatedSingleton.class));
	}

	public void testScopingAnnotationsOnAbstractTypeViaBind() {
	try {
	Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bind(A.class).to(AImpl.class);
	}
	});
	fail();
	} catch (CreationException expected) {
	assertContains(expected.getMessage(),
	A.class.getName() + " is annotated with " + Singleton.class.getName(),
	"but scope annotations are not supported for abstract types.",
	"at " + A.class.getName() + ".class(ScopesTest.java:");
	}
	}

	@Singleton
	interface A {}
	static class AImpl implements A {}

	public void testScopingAnnotationsOnAbstractTypeViaImplementedBy() {
	try {
	Guice.createInjector().getInstance(D.class);
	fail();
	} catch (ConfigurationException expected) {
	assertContains(expected.getMessage(),
	D.class.getName() + " is annotated with " + Singleton.class.getName(),
	"but scope annotations are not supported for abstract types.",
	"at " + D.class.getName() + ".class(ScopesTest.java:");
	}
	}

	@Singleton @ImplementedBy(DImpl.class)
	interface D {}
	static class DImpl implements D {}

	public void testScopingAnnotationsOnAbstractTypeViaProvidedBy() {
	try {
	Guice.createInjector().getInstance(E.class);
	fail();
	} catch (ConfigurationException expected) {
	assertContains(expected.getMessage(),
	E.class.getName() + " is annotated with " + Singleton.class.getName(),
	"but scope annotations are not supported for abstract types.",
	"at " + E.class.getName() + ".class(ScopesTest.java:");
	}
	}

	@Singleton @ProvidedBy(EProvider.class)
	interface E {}
	static class EProvider implements Provider<E> {
	public E get() {
	return null;
	}
	}

	public void testScopeUsedButNotBound() {
	try {
	Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bind(B.class).in(CustomScoped.class);
	bind(C.class);
	}
	});
	fail();
	} catch (CreationException expected) {
	assertContains(expected.getMessage(),
	"1) No scope is bound to " + CustomScoped.class.getName(),
	"at " + getClass().getName(), ".configure(ScopesTest.java:",
	"2) No scope is bound to " + CustomScoped.class.getName(),
	"at " + C.class.getName() + ".class");
	}
	}

	static class B {}

	@CustomScoped
	static class C {}

	public void testSingletonsInProductionStage() {
	Guice.createInjector(Stage.PRODUCTION, singletonsModule);

	assertEquals(1, AnnotatedSingleton.nextInstanceId);
	assertEquals(1, BoundAsSingleton.nextInstanceId);
	assertEquals(1, EagerSingleton.nextInstanceId);
	assertEquals(1, RealLinkedSingleton.nextInstanceId);
	assertEquals(1, JustInTimeSingleton.nextInstanceId);
	assertEquals(0, NotASingleton.nextInstanceId);
	}

	public void testSingletonsInDevelopmentStage() {
	Guice.createInjector(Stage.DEVELOPMENT, singletonsModule);

	assertEquals(0, AnnotatedSingleton.nextInstanceId);
	assertEquals(0, BoundAsSingleton.nextInstanceId);
	assertEquals(1, EagerSingleton.nextInstanceId);
	assertEquals(0, RealLinkedSingleton.nextInstanceId);
	assertEquals(0, JustInTimeSingleton.nextInstanceId);
	assertEquals(0, NotASingleton.nextInstanceId);
	}

	public void testSingletonScopeIsNotSerializable() throws IOException {
	Asserts.assertNotSerializable(Scopes.SINGLETON);
	}

	public void testNoScopeIsNotSerializable() throws IOException {
	Asserts.assertNotSerializable(Scopes.NO_SCOPE);
	}

	public void testUnscopedProviderWorksOutsideOfRequestedScope() {
	final RememberProviderScope scope = new RememberProviderScope();

	Injector injector = Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bindScope(CustomScoped.class, scope);
	bind(List.class).to(ArrayList.class).in(CustomScoped.class);
	}
	});

	injector.getInstance(List.class);
	Provider<?> listProvider = scope.providers.get(Key.get(List.class));

	// this line fails with a NullPointerException because the Providers
	// passed to Scope.scope() don't work outside of the scope() method.
	assertTrue(listProvider.get() instanceof ArrayList);
	}

	public void testScopeAnnotationWithoutRuntimeRetention() {
	try {
	Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bindScope(NotRuntimeRetainedScoped.class, Scopes.NO_SCOPE);
	}
	});
	fail();
	} catch (CreationException expected) {
	assertContains(expected.getMessage(),
	"1) Please annotate with @Retention(RUNTIME).",
	"at " + NotRuntimeRetainedScoped.class.getName() + ".class(ScopesTest.java:");
	}
	}

	public void testBindScopeToAnnotationWithoutScopeAnnotation() {
	try {
	Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bindScope(Deprecated.class, Scopes.NO_SCOPE);
	}
	});
	fail();
	} catch (CreationException expected) {
	assertContains(expected.getMessage(),
	"1) Please annotate with @ScopeAnnotation.",
	"at " + Deprecated.class.getName() + ".class(");
	}
	}

	public void testBindScopeTooManyTimes() {
	try {
	Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bindScope(CustomScoped.class, Scopes.NO_SCOPE);
	bindScope(CustomScoped.class, Scopes.SINGLETON);
	}
	});
	fail();
	} catch (CreationException expected) {
	assertContains(expected.getMessage(),
	"1) Scope Scopes.NO_SCOPE is already bound to " + CustomScoped.class.getName(),
	"Cannot bind Scopes.SINGLETON.",
	"at " + ScopesTest.class.getName(), ".configure(ScopesTest.java:");
	}
	}

	public void testDuplicateScopeAnnotations() {
	Injector injector = Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bindScope(CustomScoped.class, Scopes.NO_SCOPE);
	}
	});

	try {
	injector.getInstance(SingletonAndCustomScoped.class);
	fail();
	} catch (ConfigurationException expected) {
	assertContains(expected.getMessage(),
	"1) More than one scope annotation was found: ",
	"while locating " + SingletonAndCustomScoped.class.getName());
	}
	}

	public void testNullScopedAsASingleton() {
	Provider<String> unscoped = new Provider<String>() {
	final Iterator<String> values = Arrays.asList(null, "A").iterator();
	public String get() {
	return values.next();
	}
	};

	Provider<String> scoped = Scopes.SINGLETON.scope(Key.get(String.class), unscoped);
	assertNull(scoped.get());
	assertNull(scoped.get());
	assertNull(scoped.get());
	}

	class RememberProviderScope implements Scope {
	final Map<Key<?>, Provider<?>> providers = Maps.newHashMap();
	public <T> Provider<T> scope(Key<T> key, Provider<T> unscoped) {
	providers.put(key, unscoped);
	return unscoped;
	}
	}

	public void testSingletonAnnotationOnParameterizedType() {
	Injector injector = Guice.createInjector();
	assertSame(injector.getInstance(new Key<Injected<String>>() {}),
	injector.getInstance(new Key<Injected<String>>() {}));
	assertSame(injector.getInstance(new Key<In<Integer>>() {}),
	injector.getInstance(new Key<In<Short>>() {}));
	}

	@ImplementedBy(Injected.class) public interface In<T> {}
	@Singleton public static class Injected<T> implements In<T> {}

	@Target({ ElementType.TYPE, ElementType.METHOD })
	@Retention(RUNTIME)
	@ScopeAnnotation
	public @interface CustomScoped {}

	@Target({ ElementType.TYPE, ElementType.METHOD })
	@ScopeAnnotation
	public @interface NotRuntimeRetainedScoped {}

	@Singleton
	static class AnnotatedSingleton {
	static int nextInstanceId;
	final int instanceId = nextInstanceId++;
	}

	static class BoundAsSingleton {
	static int nextInstanceId;
	final int instanceId = nextInstanceId++;
	}

	static class EagerSingleton {
	static int nextInstanceId;
	final int instanceId = nextInstanceId++;
	}

	interface LinkedSingleton {}

	@Singleton
	static class RealLinkedSingleton implements LinkedSingleton {
	static int nextInstanceId;
	final int instanceId = nextInstanceId++;
	}

	static class DependsOnJustInTimeSingleton {
	@Inject JustInTimeSingleton justInTimeSingleton;
	}

	@Singleton
	static class JustInTimeSingleton {
	static int nextInstanceId;
	final int instanceId = nextInstanceId++;
	}

	static class NotASingleton {
	static int nextInstanceId;
	final int instanceId = nextInstanceId++;
	}

	@Singleton @CustomScoped
	static class SingletonAndCustomScoped {}

	@ImplementedBy(Implementation.class)
	static interface ImplementedBySingleton {}

	@ProvidedBy(ImplementationProvider.class)
	static class ProvidedBySingleton {
	static int nextInstanceId;
	final int instanceId = nextInstanceId++;
	}

	static class Implementation implements ImplementedBySingleton {
	static int nextInstanceId;
	final int instanceId = nextInstanceId++;
	}

	static class ImplementationProvider implements Provider<ProvidedBySingleton> {
	public ProvidedBySingleton get() {
	return new ProvidedBySingleton();
	}
	}

	public void testScopeThatGetsAnUnrelatedObject() {
	Injector injector = Guice.createInjector(new AbstractModule() {
	protected void configure() {
	bind(B.class);
	bind(C.class);
	ProviderGetScope providerGetScope = new ProviderGetScope();
	requestInjection(providerGetScope);
	bindScope(CustomScoped.class, providerGetScope);
	}
	});

	injector.getInstance(C.class);
	}

	class ProviderGetScope implements Scope {
	@Inject Provider<B> bProvider;

	public <T> Provider<T> scope(Key<T> key, final Provider<T> unscoped) {
	return new Provider<T>() {
	public T get() {
	bProvider.get();
	return unscoped.get();
	}
	};
	}
	}
	}