Introduce getOriginalBeanName(String) in ScopedProxyUtils

This commit introduces a utility method for retrieving the original
bean name for the target of a scoped proxy.

Closes gh-23514

spring-aop/src/main/java/org/springframework/aop/scope/ScopedProxyUtils.java

 /*
- * Copyright 2002-2017 the original author or authors.
+ * Copyright 2002-2019 the original author or authors.
  *
  * Licensed under the Apache License, Version 2.0 (the "License");
  * you may not use this file except in compliance with the License.
@@ -23,20 +23,25 @@ import org.springframework.beans.factory.support.AbstractBeanDefinition;
 import org.springframework.beans.factory.support.BeanDefinitionRegistry;
 import org.springframework.beans.factory.support.RootBeanDefinition;
 import org.springframework.lang.Nullable;
+import org.springframework.util.Assert;
 
 /**
  * Utility class for creating a scoped proxy.
- * Used by ScopedProxyBeanDefinitionDecorator and ClassPathBeanDefinitionScanner.
+ *
+ * <p>Used by ScopedProxyBeanDefinitionDecorator and ClassPathBeanDefinitionScanner.
  *
  * @author Mark Fisher
  * @author Juergen Hoeller
  * @author Rob Harrop
+ * @author Sam Brannen
  * @since 2.5
  */
 public abstract class ScopedProxyUtils {
 
 	private static final String TARGET_NAME_PREFIX = "scopedTarget.";
 
+	private static final int TARGET_NAME_PREFIX_LENGTH = TARGET_NAME_PREFIX.length();
+
 
 	/**
 	 * Generate a scoped proxy for the supplied target bean, registering the target
@@ -45,6 +50,8 @@ public abstract class ScopedProxyUtils {
 	 * @param registry the bean definition registry
 	 * @param proxyTargetClass whether to create a target class proxy
 	 * @return the scoped proxy definition
+	 * @see #getTargetBeanName(String)
+	 * @see #getOriginalBeanName(String)
 	 */
 	public static BeanDefinitionHolder createScopedProxy(BeanDefinitionHolder definition,
 			BeanDefinitionRegistry registry, boolean proxyTargetClass) {
@@ -93,11 +100,29 @@ public abstract class ScopedProxyUtils {
 	 * Generate the bean name that is used within the scoped proxy to reference the target bean.
 	 * @param originalBeanName the original name of bean
 	 * @return the generated bean to be used to reference the target bean
+	 * @see #getOriginalBeanName(String)
 	 */
 	public static String getTargetBeanName(String originalBeanName) {
 		return TARGET_NAME_PREFIX + originalBeanName;
 	}
 
+	/**
+	 * Get the original bean name for the provided {@linkplain #getTargetBeanName
+	 * target bean name}.
+	 * @param targetBeanName the target bean name for the scoped proxy
+	 * @return the original bean name
+	 * @throws IllegalArgumentException if the supplied bean name does not refer
+	 * to the target of a scoped proxy
+	 * @since 5.2
+	 * @see #getTargetBeanName(String)
+	 * @see #isScopedTarget(String)
+	 */
+	public static String getOriginalBeanName(String targetBeanName) {
+		Assert.isTrue(isScopedTarget(targetBeanName), () -> "bean name '" +
+				targetBeanName + "' does not refer to the target of a scoped proxy");
+		return targetBeanName.substring(TARGET_NAME_PREFIX_LENGTH);
+	}
+
 	/**
 	 * Specify if the {@code beanName} is the name of a bean that references the target
 	 * bean within a scoped proxy.

spring-aop/src/test/java/org/springframework/aop/scope/ScopedProxyUtilsTests.java

+/*
+ * Copyright 2002-2019 the original author or authors.
+ *
+ * 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
+ *
+ *      https://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 org.springframework.aop.scope;
+
+import org.junit.jupiter.api.Test;
+
+import static org.assertj.core.api.Assertions.assertThat;
+import static org.assertj.core.api.Assertions.assertThatIllegalArgumentException;
+
+/**
+ * Unit tests for {@link ScopedProxyUtils}.
+ *
+ * @author Sam Brannen
+ * @since 5.2
+ */
+class ScopedProxyUtilsTests {
+
+	@Test
+	void getTargetBeanNameAndIsScopedTarget() {
+		String originalBeanName = "myBean";
+		String targetBeanName = ScopedProxyUtils.getTargetBeanName(originalBeanName);
+
+		assertThat(targetBeanName).isNotEqualTo(originalBeanName).endsWith(originalBeanName);
+		assertThat(ScopedProxyUtils.isScopedTarget(targetBeanName)).isTrue();
+		assertThat(ScopedProxyUtils.isScopedTarget(originalBeanName)).isFalse();
+	}
+
+	@Test
+	void getOriginalBeanNameAndIsScopedTarget() {
+		String originalBeanName = "myBean";
+		String targetBeanName = ScopedProxyUtils.getTargetBeanName(originalBeanName);
+		String parsedOriginalBeanName = ScopedProxyUtils.getOriginalBeanName(targetBeanName);
+
+		assertThat(parsedOriginalBeanName).isNotEqualTo(targetBeanName).isEqualTo(originalBeanName);
+		assertThat(ScopedProxyUtils.isScopedTarget(targetBeanName)).isTrue();
+		assertThat(ScopedProxyUtils.isScopedTarget(parsedOriginalBeanName)).isFalse();
+	}
+
+	@Test
+	void getOriginalBeanNameForNullTargetBean() {
+		assertThatIllegalArgumentException()
+			.isThrownBy(() -> ScopedProxyUtils.getOriginalBeanName(null))
+			.withMessage("bean name 'null' does not refer to the target of a scoped proxy");
+	}
+
+	@Test
+	void getOriginalBeanNameForNonScopedTarget() {
+		assertThatIllegalArgumentException()
+			.isThrownBy(() -> ScopedProxyUtils.getOriginalBeanName("myBean"))
+			.withMessage("bean name 'myBean' does not refer to the target of a scoped proxy");
+	}
+
+}