Polish

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/ConditionalOnSingleCandidate.java

@@ -30,15 +30,14 @@ import org.springframework.context.annotation.Conditional;
  * {@link Conditional} that only matches when the specified bean class is already
  * contained in the {@link BeanFactory} and a single candidate can be determined.
  * <p>
- * The conditional will also match if multiple matching bean instances are already
+ * The condition will also match if multiple matching bean instances are already contained
- * contained in the {@link BeanFactory} but a primary candidate has been defined;
+ * in the {@link BeanFactory} but a primary candidate has been defined; essentially, the
- * essentially, the condition match if auto-wiring a bean with the defined type
+ * condition match if auto-wiring a bean with the defined type will succeed.
- * will succeed.
  *
  * @author Stephane Nicoll
  * @since 1.3.0
  */
-@Target({ElementType.TYPE, ElementType.METHOD})
+@Target({ ElementType.TYPE, ElementType.METHOD })
 @Retention(RetentionPolicy.RUNTIME)
 @Documented
 @Conditional(OnBeanCondition.class)
@@ -48,8 +47,9 @@ public @interface ConditionalOnSingleCandidate {
 	 * The class type of bean that should be checked. The condition match if the class
 	 * specified is contained in the {@link ApplicationContext} and a primary candidate
 	 * exists in case of multiple instances.
-	 * <p>This attribute may <strong>not</strong> be used in conjunction with
+	 * <p>
-	 * {@link #type()}, but it may be used instead of {@link #type()}.
+	 * This attribute may <strong>not</strong> be used in conjunction with {@link #type()}
+	 * , but it may be used instead of {@link #type()}.
 	 * @return the class type of the bean to check
 	 */
 	Class<?> value() default Object.class;
@@ -58,7 +58,8 @@ public @interface ConditionalOnSingleCandidate {
 	 * The class type name of bean that should be checked. The condition matches if the
 	 * class specified is contained in the {@link ApplicationContext} and a primary
 	 * candidate exists in case of multiple instances.
-	 * <p>This attribute may <strong>not</strong> be used in conjunction with
+	 * <p>
+	 * This attribute may <strong>not</strong> be used in conjunction with
 	 * {@link #value()}, but it may be used instead of {@link #value()}.
 	 * @return the class type name of the bean to check
 	 */

spring-boot-autoconfigure/src/main/java/org/springframework/boot/autoconfigure/condition/OnBeanCondition.java

@@ -24,12 +24,10 @@ import java.util.Collection;
 import java.util.Collections;
 import java.util.LinkedHashSet;
 import java.util.List;
-import java.util.ListIterator;
 import java.util.Set;
 
 import org.apache.commons.logging.Log;
 import org.apache.commons.logging.LogFactory;
-
 import org.springframework.beans.factory.BeanFactory;
 import org.springframework.beans.factory.HierarchicalBeanFactory;
 import org.springframework.beans.factory.ListableBeanFactory;
@@ -100,15 +98,13 @@ public class OnBeanCondition extends SpringBootCondition implements
 				return ConditionOutcome.noMatch("@ConditionalOnSingleCandidate " + spec
 						+ " found no beans");
 			}
-			else if (hasSingleAutowireCandidate(context.getBeanFactory(), matching)) {
+			else if (!hasSingleAutowireCandidate(context.getBeanFactory(), matching)) {
-				matchMessage.append("@ConditionalOnSingleCandidate " + spec + " found a primary " +
-						"candidate amongst the following " + matching);
-			}
-			else {
 				return ConditionOutcome.noMatch("@ConditionalOnSingleCandidate " + spec
-						+ " found no primary candidate amongst the"
+						+ " found no primary candidate amongst the" + " following "
-						+ " following " + matching);
+						+ matching);
 			}
+			matchMessage.append("@ConditionalOnSingleCandidate " + spec + " found "
+					+ "a primary candidate amongst the following " + matching);
 		}
 		if (metadata.isAnnotated(ConditionalOnMissingBean.class.getName())) {
 			BeanSearchSpec spec = new BeanSearchSpec(context, metadata,
@@ -221,23 +217,21 @@ public class OnBeanCondition extends SpringBootCondition implements
 		}
 	}
 
-	private boolean hasSingleAutowireCandidate(ConfigurableListableBeanFactory beanFactory,
+	private boolean hasSingleAutowireCandidate(
-			List<String> beans) {
+			ConfigurableListableBeanFactory beanFactory, List<String> beanNames) {
+		return (beanNames.size() == 1 || getPrimaryBeans(beanFactory, beanNames).size() == 1);
+	}
 
-		if (beans.size() == 1) {
+	private List<String> getPrimaryBeans(ConfigurableListableBeanFactory beanFactory,
-			return true;
+			List<String> beanNames) {
-		}
+		List<String> primaryBeans = new ArrayList<String>();
-		boolean primaryFound = false;
+		for (String beanName : beanNames) {
-		for (String bean : beans) {
+			BeanDefinition beanDefinition = beanFactory.getBeanDefinition(beanName);
-			BeanDefinition beanDefinition = beanFactory.getBeanDefinition(bean);
 			if (beanDefinition != null && beanDefinition.isPrimary()) {
-				if (primaryFound) {
+				primaryBeans.add(beanName);
-					return false;
-				}
-				primaryFound = true;
 			}
 		}
-		return primaryFound;
+		return primaryBeans;
 	}
 
 	private static class BeanSearchSpec {
@@ -288,8 +282,7 @@ public class OnBeanCondition extends SpringBootCondition implements
 			return "@" + ClassUtils.getShortName(this.annotationType);
 		}
 
-		@SuppressWarnings({ "unchecked", "rawtypes" })
+		protected void collect(MultiValueMap<String, Object> attributes, String key,
-		private void collect(MultiValueMap<String, Object> attributes, String key,
 				List<String> destination) {
 			List<?> values = attributes.get(key);
 			if (values != null) {
@@ -388,18 +381,17 @@ public class OnBeanCondition extends SpringBootCondition implements
 			super(context, metadata, annotationType);
 		}
 
+		@Override
+		protected void collect(MultiValueMap<String, Object> attributes, String key,
+				List<String> destination) {
+			super.collect(attributes, key, destination);
+			destination.removeAll(Arrays.asList("", Object.class.getName()));
+		}
+
 		@Override
 		protected void validate() {
-			List<String> types = getTypes();
+			Assert.isTrue(getTypes().size() == 1, annotationName() + " annotations must "
-			ListIterator<String> it = types.listIterator();
+					+ "specify only one type (got " + getTypes() + ")");
-			while (it.hasNext()) {
-				String value = it.next();
-				if (!StringUtils.hasText(value) || Object.class.getName().equals(value)) {
-					it.remove();
-				}
-			}
-			Assert.isTrue(types.size() == 1, annotationName() + " annotations must "
-					+ "specify only one type (got " + types + ")");
 
 		}
 	}

spring-boot-autoconfigure/src/test/java/org/springframework/boot/autoconfigure/condition/ConditionalOnSingleCandidateTests.java

@@ -20,7 +20,6 @@ import org.junit.After;
 import org.junit.Rule;
 import org.junit.Test;
 import org.junit.rules.ExpectedException;
-
 import org.springframework.context.annotation.AnnotationConfigApplicationContext;
 import org.springframework.context.annotation.Bean;
 import org.springframework.context.annotation.Configuration;
@@ -58,8 +57,7 @@ public class ConditionalOnSingleCandidateTests {
 
 	@Test
 	public void singleCandidateOneCandidate() {
-		load(FooConfiguration.class,
+		load(FooConfiguration.class, OnBeanSingleCandidateConfiguration.class);
-				OnBeanSingleCandidateConfiguration.class);
 		assertTrue(this.context.containsBean("baz"));
 		assertEquals("foo", this.context.getBean("baz"));
 	}
@@ -88,17 +86,19 @@ public class ConditionalOnSingleCandidateTests {
 
 	@Test
 	public void invalidAnnotationTwoTypes() {
-		thrown.expect(IllegalStateException.class);
+		this.thrown.expect(IllegalStateException.class);
-		thrown.expectCause(isA(IllegalArgumentException.class));
+		this.thrown.expectCause(isA(IllegalArgumentException.class));
-		thrown.expectMessage(OnBeanSingleCandidateTwoTypesConfiguration.class.getName());
+		this.thrown.expectMessage(OnBeanSingleCandidateTwoTypesConfiguration.class
+				.getName());
 		load(OnBeanSingleCandidateTwoTypesConfiguration.class);
 	}
 
 	@Test
 	public void invalidAnnotationNoType() {
-		thrown.expect(IllegalStateException.class);
+		this.thrown.expect(IllegalStateException.class);
-		thrown.expectCause(isA(IllegalArgumentException.class));
+		this.thrown.expectCause(isA(IllegalArgumentException.class));
-		thrown.expectMessage(OnBeanSingleCandidateNoTypeConfiguration.class.getName());
+		this.thrown.expectMessage(OnBeanSingleCandidateNoTypeConfiguration.class
+				.getName());
 		load(OnBeanSingleCandidateNoTypeConfiguration.class);
 	}
 
@@ -110,10 +110,12 @@ public class ConditionalOnSingleCandidateTests {
 	@Configuration
 	@ConditionalOnSingleCandidate(value = String.class)
 	protected static class OnBeanSingleCandidateConfiguration {
+
 		@Bean
 		public String baz(String s) {
 			return s;
 		}
+
 	}
 
 	@Configuration
@@ -130,35 +132,43 @@ public class ConditionalOnSingleCandidateTests {
 
 	@Configuration
 	protected static class FooConfiguration {
+
 		@Bean
 		public String foo() {
 			return "foo";
 		}
+
 	}
 
 	@Configuration
 	protected static class FooPrimaryConfiguration {
+
 		@Bean
 		@Primary
 		public String foo() {
 			return "foo";
 		}
+
 	}
 
 	@Configuration
 	protected static class BarConfiguration {
+
 		@Bean
 		public String bar() {
 			return "bar";
 		}
+
 	}
 
 	@Configuration
 	protected static class BarPrimaryConfiguration {
+
 		@Bean
 		@Primary
 		public String bar() {
 			return "bar";
 		}
+
 	}
 }