Polish: do simple clean-up

spring-beans/src/main/java/org/springframework/beans/factory/config/YamlProcessor.java

@@ -156,8 +156,7 @@ public abstract class YamlProcessor {
 			if (logger.isDebugEnabled()) {
 				logger.debug("Loading from YAML: " + resource);
 			}
-			Reader reader = new UnicodeReader(resource.getInputStream());
-			try {
+			try (Reader reader = new UnicodeReader(resource.getInputStream())) {
 				for (Object object : yaml.loadAll(reader)) {
 					if (object != null && process(asMap(object), callback)) {
 						count++;
@@ -171,9 +170,6 @@ public abstract class YamlProcessor {
 							" from YAML resource: " + resource);
 				}
 			}
-			finally {
-				reader.close();
-			}
 		}
 		catch (IOException ex) {
 			handleProcessError(resource, ex);

spring-beans/src/main/java/org/springframework/beans/factory/support/AbstractBeanDefinition.java

@@ -663,7 +663,7 @@ public abstract class AbstractBeanDefinition extends BeanMetadataAttributeAccess
 	 * Return whether this bean has the specified qualifier.
 	 */
 	public boolean hasQualifier(String typeName) {
-		return this.qualifiers.keySet().contains(typeName);
+		return this.qualifiers.containsKey(typeName);
 	}
 
 	/**

spring-messaging/src/main/java/org/springframework/messaging/simp/stomp/StompDecoder.java

@@ -267,7 +267,7 @@ public class StompDecoder {
 			if (index + 1 >= inString.length()) {
 				throw new StompConversionException("Illegal escape sequence at index " + index + ": " + inString);
 			}
-			Character c = inString.charAt(index + 1);
+			char c = inString.charAt(index + 1);
 			if (c == 'r') {
 				sb.append('\r');
 			}