Extract LOGGER_CONTEXT_CLASS_NAME constant and unify log messages

- Moved the repeated string "org.apache.logging.log4j.core.LoggerContext" to a private static final constant
- Used the constant in Class.forName() and ConditionOutcome messages
- Unified inconsistent messages: changed "Logger context" to "LoggerContext" for consistency with the class name

Signed-off-by: wonyongg <[email protected]>

Author: wonyongg

spring-boot-project/spring-boot-actuator-autoconfigure/src/main/java/org/springframework/boot/actuate/autoconfigure/metrics/Log4J2MetricsAutoConfiguration.java

@@ -54,20 +54,22 @@ public Log4j2Metrics log4j2Metrics() {
 
 	static class Log4JCoreLoggerContextCondition extends SpringBootCondition {
 
+		private static final String LOGGER_CONTEXT_CLASS_NAME = "org.apache.logging.log4j.core.LoggerContext";
+
 		@Override
 		public ConditionOutcome getMatchOutcome(ConditionContext context, AnnotatedTypeMetadata metadata) {
 			LoggerContext loggerContext = LogManager.getContext(false);
 			try {
-				if (Class.forName("org.apache.logging.log4j.core.LoggerContext").isInstance(loggerContext)) {
+				if (Class.forName(LOGGER_CONTEXT_CLASS_NAME).isInstance(loggerContext)) {
 					return ConditionOutcome
-						.match("LoggerContext was an instance of org.apache.logging.log4j.core.LoggerContext");
+						.match("LoggerContext was an instance of " + LOGGER_CONTEXT_CLASS_NAME);
 				}
 			}
 			catch (Throwable ex) {
 				// Continue with no match
 			}
 			return ConditionOutcome
-				.noMatch("Logger context was not an instance of org.apache.logging.log4j.core.LoggerContext");
+				.noMatch("LoggerContext was not an instance of " + LOGGER_CONTEXT_CLASS_NAME);
 		}
 
 	}