Ensure that logging system tests do not leave log files open

See gh-17107

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/context/config/ConfigFileApplicationListenerTests.java

@@ -28,10 +28,10 @@ import java.util.Properties;
 import java.util.stream.Collectors;
 import java.util.stream.StreamSupport;
 
+import org.apache.commons.logging.Log;
+import org.apache.commons.logging.LogFactory;
 import org.apache.logging.log4j.Level;
-import org.apache.logging.log4j.LogManager;
-import org.apache.logging.log4j.core.LoggerContext;
-import org.apache.logging.log4j.core.config.LoggerConfig;
+import org.apache.logging.log4j.core.Logger;
 import org.assertj.core.api.Condition;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.Test;
@@ -61,6 +61,7 @@ import org.springframework.core.io.ByteArrayResource;
 import org.springframework.core.io.Resource;
 import org.springframework.core.io.ResourceLoader;
 import org.springframework.test.context.support.TestPropertySourceUtils;
+import org.springframework.test.util.ReflectionTestUtils;
 import org.springframework.util.StringUtils;
 
 import static org.assertj.core.api.Assertions.assertThat;
@@ -495,17 +496,15 @@ class ConfigFileApplicationListenerTests {
 	}
 
 	private void withDebugLogging(Runnable runnable) {
-		LoggerContext loggingContext = (LoggerContext) LogManager.getContext(false);
-		org.apache.logging.log4j.core.config.Configuration configuration = loggingContext.getConfiguration();
-		configuration.addLogger(ConfigFileApplicationListener.class.getName(),
-				new LoggerConfig(ConfigFileApplicationListener.class.getName(), Level.DEBUG, true));
-		loggingContext.updateLoggers();
+		Log log = LogFactory.getLog(ConfigFileApplicationListener.class);
+		Logger logger = (Logger) ReflectionTestUtils.getField(log, "logger");
+		Level previousLevel = logger.getLevel();
+		logger.setLevel(Level.DEBUG);
 		try {
 			runnable.run();
 		}
 		finally {
-			configuration.removeLogger(ConfigFileApplicationListener.class.getName());
-			loggingContext.updateLoggers();
+			logger.setLevel(previousLevel);
 		}
 	}
 

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/java/JavaLoggingSystemTests.java

@@ -70,6 +70,7 @@ class JavaLoggingSystemTests extends AbstractLoggingSystemTests {
 	@AfterEach
 	void resetLogger() {
 		this.logger.setLevel(Level.OFF);
+		this.loggingSystem.getShutdownHandler().run();
 	}
 
 	@AfterEach

spring-boot-project/spring-boot/src/test/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystemTests.java

@@ -29,6 +29,7 @@ import org.apache.logging.log4j.LogManager;
 import org.apache.logging.log4j.Logger;
 import org.apache.logging.log4j.core.LoggerContext;
 import org.apache.logging.log4j.core.config.Configuration;
+import org.apache.logging.log4j.core.config.Reconfigurable;
 import org.junit.jupiter.api.AfterEach;
 import org.junit.jupiter.api.BeforeEach;
 import org.junit.jupiter.api.Test;
@@ -66,8 +67,12 @@ class Log4J2LoggingSystemTests extends AbstractLoggingSystemTests {
 
 	private Logger logger;
 
+	private Configuration configuration;
+
 	@BeforeEach
 	void setup() {
+		LoggerContext loggerContext = (LoggerContext) LogManager.getContext(false);
+		this.configuration = loggerContext.getConfiguration();
 		this.loggingSystem.cleanUp();
 		this.logger = LogManager.getLogger(getClass());
 	}
@@ -75,6 +80,9 @@ class Log4J2LoggingSystemTests extends AbstractLoggingSystemTests {
 	@AfterEach
 	void cleanUp() {
 		this.loggingSystem.cleanUp();
+		LoggerContext loggerContext = (LoggerContext) LogManager.getContext(false);
+		loggerContext.stop();
+		loggerContext.start(((Reconfigurable) this.configuration).reconfigure());
 	}
 
 	@Test