From 65b6d8f4f7b695afecc484ac04544b44107a9984 Mon Sep 17 00:00:00 2001
From: Stephane Nicoll <snicoll@pivotal.io>
Date: Thu, 24 Nov 2016 09:58:32 +0100
Subject: [PATCH] Handle `NoClassDefFoundError` in `OnBeanCondition`

If `OnBeanCondition` is used with a `String` literal representing the
fully qualified name of a bean and such type does not exist, it
gracefully manages it as if it was not found. Prior to this commit, an
exception would be thrown if any related class such as the parent
class does not exist.

This commit handles this additional case, catching `NoClassDefFoundError`
the same way it did handle `ClassNotFoundException`. That way, a
missing type will now be considered as absent if it's not on the
classpath.

Closes gh-7459
---
 .../condition/OnBeanCondition.java            |  3 +
 ...MissingBeanWithFilteredClasspathTests.java | 71 +++++++++++++++++++
 2 files changed, 74 insertions(+)
 create mode 100644 spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingBeanWithFilteredClasspathTests.java

diff --git a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java
index 95680f74e6..5ec455115b 100644
--- a/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java
+++ b/spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java
@@ -177,6 +177,9 @@ class OnBeanCondition extends SpringBootCondition implements ConfigurationCondit
 		catch (ClassNotFoundException ex) {
 			return Collections.emptySet();
 		}
+		catch (NoClassDefFoundError ex) {
+			return Collections.emptySet();
+		}
 	}
 
 	private void collectBeanNamesForType(Set<String> result,
diff --git a/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingBeanWithFilteredClasspathTests.java b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingBeanWithFilteredClasspathTests.java
new file mode 100644
index 0000000000..e19f41e09a
--- /dev/null
+++ b/spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnMissingBeanWithFilteredClasspathTests.java
@@ -0,0 +1,71 @@
+/*
+ * Copyright 2012-2016 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
+ *
+ *      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 org.springframework.boot.autoconfigure.condition;
+
+import org.junit.After;
+import org.junit.Test;
+import org.junit.runner.RunWith;
+
+import org.springframework.boot.testutil.ClassPathExclusions;
+import org.springframework.boot.testutil.FilteredClassPathRunner;
+import org.springframework.cache.caffeine.CaffeineCacheManager;
+import org.springframework.context.annotation.AnnotationConfigApplicationContext;
+import org.springframework.context.annotation.Bean;
+import org.springframework.context.annotation.Configuration;
+
+import static org.assertj.core.api.Assertions.assertThat;
+
+/**
+ * Tests {@link ConditionalOnMissingBean} with filtered classpath.
+ *
+ * @author Stephane Nicoll
+ * @author Andy Wilkinson
+ */
+@RunWith(FilteredClassPathRunner.class)
+@ClassPathExclusions("spring-context-support-*.jar")
+public class ConditionalOnMissingBeanWithFilteredClasspathTests {
+
+	private final AnnotationConfigApplicationContext context = new AnnotationConfigApplicationContext();
+
+	@After
+	public void closeContext() {
+		this.context.close();
+	}
+
+	@Test
+	public void testNameOnMissingBeanTypeWithMissingImport() {
+		this.context.register(OnBeanTypeConfiguration.class);
+		this.context.refresh();
+		assertThat(this.context.containsBean("foo")).isTrue();
+	}
+
+
+	@Configuration
+	static class OnBeanTypeConfiguration {
+
+		@Bean
+		@ConditionalOnMissingBean(type = "org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBeanWithFilteredClasspathTests.TestCacheManager")
+		public String foo() {
+			return "foo";
+		}
+
+	}
+
+	static class TestCacheManager extends CaffeineCacheManager {
+	}
+
+}