Polish some Map operations

Closes gh-15153

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/cloudfoundry/servlet/TokenValidator.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -84,12 +84,7 @@ class TokenValidator {
 	}
 
 	private boolean hasValidKeyId(String tokenKey) {
-		for (String candidate : this.tokenKeys.keySet()) {
-			if (tokenKey.equals(candidate)) {
-				return true;
-			}
-		}
-		return false;
+		return this.tokenKeys.containsKey(tokenKey);
 	}
 
 	private boolean hasValidSignature(Token token, String key) {

spring-boot-project/spring-boot-test-autoconfigure/src/test/java/org/springframework/boot/test/autoconfigure/AutoConfigurationImportedCondition.java

@@ -1,5 +1,5 @@
 /*
- * Copyright 2012-2017 the original author or authors.
+ * Copyright 2012-2018 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.
@@ -43,8 +43,8 @@ public final class AutoConfigurationImportedCondition
 		ConditionEvaluationReport report = ConditionEvaluationReport
 				.get((ConfigurableListableBeanFactory) context
 						.getAutowireCapableBeanFactory());
-		return report.getConditionAndOutcomesBySource().keySet()
-				.contains(this.autoConfigurationClass.getName());
+		return report.getConditionAndOutcomesBySource()
+				.containsKey(this.autoConfigurationClass.getName());
 	}
 
 	/**