Merge pull request #43931 from nosan

* pr/43931:
  Polish Logback StatusListener code
  Register Logback StatusListener when using custom Logback file

Closes gh-43931

Author: philwebb

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/logback/FilteringStatusListener.java

@@ -35,11 +35,8 @@
 import ch.qos.logback.classic.turbo.TurboFilter;
 import ch.qos.logback.core.joran.spi.JoranException;
 import ch.qos.logback.core.spi.FilterReply;
-import ch.qos.logback.core.status.OnConsoleStatusListener;
-import ch.qos.logback.core.status.OnErrorConsoleStatusListener;
 import ch.qos.logback.core.status.Status;
 import ch.qos.logback.core.status.StatusUtil;
-import ch.qos.logback.core.util.StatusListenerConfigHelper;
 import ch.qos.logback.core.util.StatusPrinter2;
 import org.slf4j.ILoggerFactory;
 import org.slf4j.Logger;
@@ -216,6 +213,7 @@ private boolean initializeFromAotGeneratedArtifactsIfPossible(LoggingInitializat
 		LoggerContext loggerContext = getLoggerContext();
 		stopAndReset(loggerContext);
 		withLoggingSuppressed(() -> putInitializationContextObjects(loggerContext, initializationContext));
+		SystemStatusListener.addTo(loggerContext);
 		SpringBootJoranConfigurator configurator = new SpringBootJoranConfigurator(initializationContext);
 		configurator.setContext(loggerContext);
 		boolean configuredUsingAotGeneratedArtifacts = configurator.configureUsingAotGeneratedArtifacts();
@@ -230,21 +228,16 @@ protected void loadDefaults(LoggingInitializationContext initializationContext,
 		LoggerContext loggerContext = getLoggerContext();
 		stopAndReset(loggerContext);
 		withLoggingSuppressed(() -> {
-			putInitializationContextObjects(loggerContext, initializationContext);
 			boolean debug = Boolean.getBoolean("logback.debug");
-			if (debug) {
-				StatusListenerConfigHelper.addOnConsoleListenerInstance(loggerContext, new OnConsoleStatusListener());
-			}
-			else {
-				addOnErrorConsoleStatusListener(loggerContext);
-			}
+			putInitializationContextObjects(loggerContext, initializationContext);
+			SystemStatusListener.addTo(loggerContext, debug);
 			Environment environment = initializationContext.getEnvironment();
 			// Apply system properties directly in case the same JVM runs multiple apps
 			new LogbackLoggingSystemProperties(environment, getDefaultValueResolver(environment),
 					loggerContext::putProperty)
 				.apply(logFile);
-			LogbackConfigurator configurator = debug ? new DebugLogbackConfigurator(loggerContext)
-					: new LogbackConfigurator(loggerContext);
+			LogbackConfigurator configurator = (!debug) ? new LogbackConfigurator(loggerContext)
+					: new DebugLogbackConfigurator(loggerContext);
 			new DefaultLogbackConfiguration(logFile).apply(configurator);
 			loggerContext.setPackagingDataEnabled(true);
 			loggerContext.start();
@@ -261,6 +254,7 @@ protected void loadConfiguration(LoggingInitializationContext initializationCont
 			if (initializationContext != null) {
 				applySystemProperties(initializationContext.getEnvironment(), logFile);
 			}
+			SystemStatusListener.addTo(loggerContext);
 			try {
 				Resource resource = ApplicationResourceLoader.get().getResource(location);
 				configureByResourceUrl(initializationContext, loggerContext, resource.getURL());
@@ -491,15 +485,6 @@ private void withLoggingSuppressed(Runnable action) {
 		}
 	}
 
-	private void addOnErrorConsoleStatusListener(LoggerContext context) {
-		FilteringStatusListener listener = new FilteringStatusListener(new OnErrorConsoleStatusListener(),
-				Status.ERROR);
-		listener.setContext(context);
-		if (context.getStatusManager().add(listener)) {
-			listener.start();
-		}
-	}
-
 	void setStatusPrinterStream(PrintStream stream) {
 		this.statusPrinter.setPrintStream(stream);
 	}

spring-boot-project/spring-boot/src/main/java/org/springframework/boot/logging/logback/LogbackLoggingSystem.java

@@ -0,0 +1,65 @@
+/*
+ * Copyright 2012-2025 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.
+ * You may obtain a copy of the License at
+ *
+ *      https://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package org.springframework.boot.logging.logback;
+
+import java.io.PrintStream;
+
+import ch.qos.logback.classic.LoggerContext;
+import ch.qos.logback.core.status.OnPrintStreamStatusListenerBase;
+import ch.qos.logback.core.status.Status;
+import ch.qos.logback.core.status.StatusListener;
+
+/**
+ * {@link StatusListener} used to print appropriate status messages to {@link System#out}
+ * or {@link System#err}.
+ *
+ * @author Dmytro Nosan
+ * @author Phillip Webb
+ */
+final class SystemStatusListener extends OnPrintStreamStatusListenerBase {
+
+	private final boolean debug;
+
+	private SystemStatusListener(boolean debug) {
+		this.debug = debug;
+	}
+
+	@Override
+	public void addStatusEvent(Status status) {
+		if (this.debug || status.getLevel() >= Status.WARN) {
+			super.addStatusEvent(status);
+		}
+	}
+
+	@Override
+	protected PrintStream getPrintStream() {
+		return (!this.debug) ? System.err : System.out;
+	}
+
+	static void addTo(LoggerContext loggerContext) {
+		addTo(loggerContext, false);
+	}
+
+	static void addTo(LoggerContext loggerContext, boolean debug) {
+		SystemStatusListener listener = new SystemStatusListener(debug);
+		listener.setContext(loggerContext);
+		if (loggerContext.getStatusManager().add(listener)) {
+			listener.start();
+		}
+	}
+
+}