Support Gradle-style Kotlin bean API

val context = GenericApplicationContext {
    registerBean<Foo>()
    registerBean { Bar(it.getBean<Foo>()) }
}

Issue: SPR-15126

spring-beans/src/main/kotlin/org/springframework/beans/factory/BeanFactoryExtension.kt

@@ -15,16 +15,33 @@ object BeanFactoryExtension {
 	 */
 	fun <T : Any> BeanFactory.getBean(requiredType: KClass<T>) = getBean(requiredType.java)
 
+	/**
+	 * @see BeanFactory.getBean(Class<T>)
+	 */
+	inline fun <reified T : Any> BeanFactory.getBean() = getBean(T::class.java)
+
 	/**
 	 * @see BeanFactory.getBean(String, Class<T>)
 	 */
 	fun <T : Any> BeanFactory.getBean(name: String, requiredType: KClass<T>) =
 			getBean(name, requiredType.java)
 
+	/**
+	 * @see BeanFactory.getBean(String, Class<T>)
+	 */
+	inline fun <reified T : Any> BeanFactory.getBean(name: String) =
+			getBean(name, T::class.java)
+
 	/**
 	 * @see BeanFactory.getBean(Class<T>, Object...)
 	 */
 	fun <T : Any> BeanFactory.getBean(requiredType: KClass<T>, vararg args:Any) =
 			getBean(requiredType.java, *args)
 
+	/**
+	 * @see BeanFactory.getBean(Class<T>, Object...)
+	 */
+	inline fun <reified T : Any> BeanFactory.getBean(vararg args:Any) =
+			getBean(T::class.java, *args)
+
 }

spring-beans/src/main/kotlin/org/springframework/beans/factory/ListableBeanFactoryExtension.kt

@@ -16,6 +16,12 @@ object ListableBeanFactoryExtension {
 	fun <T : Any> ListableBeanFactory.getBeanNamesForType(type: KClass<T>) =
 			getBeanNamesForType(type.java)
 
+	/**
+	 * @see ListableBeanFactory.getBeanNamesForType(Class<?>)
+	 */
+	inline fun <reified T : Any> ListableBeanFactory.getBeanNamesForType() =
+			getBeanNamesForType(T::class.java)
+
 	/**
 	 * @see ListableBeanFactory.getBeanNamesForType(Class<?>, boolean, boolean)
 	 */
@@ -23,12 +29,24 @@ object ListableBeanFactoryExtension {
 			includeNonSingletons: Boolean, allowEagerInit: Boolean) =
 					getBeanNamesForType(type.java, includeNonSingletons, allowEagerInit)
 
+	/**
+	 * @see ListableBeanFactory.getBeanNamesForType(Class<?>, boolean, boolean)
+	 */
+	inline fun <reified T : Any> ListableBeanFactory.getBeanNamesForType(includeNonSingletons: Boolean, allowEagerInit: Boolean) =
+					getBeanNamesForType(T::class.java, includeNonSingletons, allowEagerInit)
+
 	/**
 	 * @see ListableBeanFactory.getBeansOfType(Class<T>)
 	 */
 	fun <T : Any> ListableBeanFactory.getBeansOfType(type: KClass<T>) =
 			getBeansOfType(type.java)
 
+	/**
+	 * @see ListableBeanFactory.getBeansOfType(Class<T>)
+	 */
+	inline fun <reified T : Any> ListableBeanFactory.getBeansOfType() =
+			getBeansOfType(T::class.java)
+
 	/**
 	 * @see ListableBeanFactory.getBeansOfType(Class<T>, boolean, boolean)
 	 */
@@ -36,22 +54,46 @@ object ListableBeanFactoryExtension {
 			includeNonSingletons: Boolean, allowEagerInit: Boolean) =
 					getBeansOfType(type.java, includeNonSingletons, allowEagerInit)
 
+	/**
+	 * @see ListableBeanFactory.getBeansOfType(Class<T>, boolean, boolean)
+	 */
+	inline fun <reified T : Any> ListableBeanFactory.getBeansOfType(includeNonSingletons: Boolean, allowEagerInit: Boolean) =
+					getBeansOfType(T::class.java, includeNonSingletons, allowEagerInit)
+
 	/**
 	 * @see ListableBeanFactory.getBeanNamesForAnnotation
 	 */
 	fun <T : Annotation> ListableBeanFactory.getBeanNamesForAnnotation(type: KClass<T>) =
 			getBeanNamesForAnnotation(type.java)
 
+	/**
+	 * @see ListableBeanFactory.getBeanNamesForAnnotation
+	 */
+	inline fun <reified T : Annotation> ListableBeanFactory.getBeanNamesForAnnotation() =
+			getBeanNamesForAnnotation(T::class.java)
+
 	/**
 	 * @see ListableBeanFactory.getBeansWithAnnotation
 	 */
 	fun <T : Annotation> ListableBeanFactory.getBeansWithAnnotation(type: KClass<T>) =
 			getBeansWithAnnotation(type.java)
 
+	/**
+	 * @see ListableBeanFactory.getBeansWithAnnotation
+	 */
+	inline fun <reified T : Annotation> ListableBeanFactory.getBeansWithAnnotation() =
+			getBeansWithAnnotation(T::class.java)
+
 	/**
 	 * @see ListableBeanFactoryExtension.findAnnotationOnBean
 	 */
 	fun <T : Annotation> ListableBeanFactory.findAnnotationOnBean(beanName:String, type: KClass<T>) =
 			findAnnotationOnBean(beanName, type.java)
 
+	/**
+	 * @see ListableBeanFactoryExtension.findAnnotationOnBean
+	 */
+	inline fun <reified T : Annotation> ListableBeanFactory.findAnnotationOnBean(beanName:String) =
+			findAnnotationOnBean(beanName, T::class.java)
+
 }

spring-context/src/main/kotlin/org/springframework/context/support/GenericApplicationContextExtension.kt

@@ -23,6 +23,13 @@ object GenericApplicationContextExtension {
 					registerBean(beanClass.java, *customizers)
 	}
 
+	/**
+	 * @see GenericApplicationContext.registerBean(Class<T>, BeanDefinitionCustomizer...)
+	 */
+	inline fun <reified T : Any> GenericApplicationContext.registerBean(vararg customizers: BeanDefinitionCustomizer) {
+					registerBean(T::class.java, *customizers)
+	}
+
 	/**
 	 * @see GenericApplicationContext.registerBean(String, Class<T>, BeanDefinitionCustomizer...)
 	 */
@@ -31,6 +38,13 @@ object GenericApplicationContextExtension {
 					registerBean(beanName, beanClass.java, *customizers)
 	}
 
+	/**
+	 * @see GenericApplicationContext.registerBean(String, Class<T>, BeanDefinitionCustomizer...)
+	 */
+	inline fun <reified T : Any> GenericApplicationContext.registerBean(beanName: String, vararg customizers: BeanDefinitionCustomizer) {
+					registerBean(beanName, T::class.java, *customizers)
+	}
+
 	/**
 	 * @see GenericApplicationContext.registerBean(Class<T>, Supplier<T>, BeanDefinitionCustomizer...)
 	 */
@@ -46,4 +60,6 @@ object GenericApplicationContextExtension {
 			vararg customizers: BeanDefinitionCustomizer, crossinline function: (ApplicationContext) -> T) {
 					registerBean(name, T::class.java, Supplier { function.invoke(this) }, *customizers)
 	}
+
+	fun GenericApplicationContext(configure: GenericApplicationContext.()->Unit) = GenericApplicationContext().apply(configure)
 }

spring-context/src/test/kotlin/org/springframework/context/support/GenericApplicationContextExtensionTests.kt

@@ -4,6 +4,7 @@ import org.junit.Assert.assertNotNull
 import org.junit.Test
 import org.springframework.context.support.GenericApplicationContextExtension.registerBean
 import org.springframework.beans.factory.BeanFactoryExtension.getBean
+import org.springframework.context.support.GenericApplicationContextExtension.GenericApplicationContext
 
 class GenericApplicationContextExtensionTests {
 
@@ -59,6 +60,17 @@ class GenericApplicationContextExtensionTests {
 		assertNotNull(context.getBean("b"))
 	}
 
+	@Test
+	fun registerBeanWithGradleStyleApi() {
+		val context = GenericApplicationContext {
+			registerBean<BeanA>()
+			registerBean { BeanB(it.getBean<BeanA>()) }
+		}
+		context.refresh()
+		assertNotNull(context.getBean<BeanA>())
+		assertNotNull(context.getBean<BeanB>())
+	}
+
 	internal class BeanA
 
 	internal class BeanB(val a: BeanA)