Skip to content

Console output may be lost when using Log4j2 with something that replaces System.out #44380

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Closed
wants to merge 1 commit into from
Closed

Console output may be lost when using Log4j2 with something that replaces System.out #44380

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
1 commit
Select commit
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
32 changes: 14 additions & 18 deletions ...pring-boot/src/main/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystem.java
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -47,6 +47,7 @@
import org.apache.logging.log4j.core.util.AuthorizationProvider;
import org.apache.logging.log4j.core.util.NameUtil;
import org.apache.logging.log4j.jul.Log4jBridgeHandler;
import org.apache.logging.log4j.status.StatusConsoleListener;
import org.apache.logging.log4j.status.StatusLogger;
import org.apache.logging.log4j.util.PropertiesUtil;

Expand Down Expand Up @@ -93,6 +94,9 @@ public class Log4J2LoggingSystem extends AbstractLoggingSystem {
static final String ENVIRONMENT_KEY = Conventions.getQualifiedAttributeName(Log4J2LoggingSystem.class,
"environment");

static final String STATUS_LISTENER_KEY = Conventions.getQualifiedAttributeName(Log4J2LoggingSystem.class,
"statusListener");

private static final LogLevels<Level> LEVELS = new LogLevels<>();

static {
Expand Down Expand Up @@ -214,10 +218,12 @@ public void initialize(LoggingInitializationContext initializationContext, Strin
if (isAlreadyInitialized(loggerContext)) {
return;
}
resetFallbackListenerStream(StatusLogger.getLogger());
StatusConsoleListener listener = new StatusConsoleListener(Level.WARN);
StatusLogger.getLogger().registerListener(listener);
loggerContext.putObject(STATUS_LISTENER_KEY, listener);
Environment environment = initializationContext.getEnvironment();
if (environment != null) {
getLoggerContext().putObject(ENVIRONMENT_KEY, environment);
loggerContext.putObject(ENVIRONMENT_KEY, environment);
Log4J2LoggingSystem.propertySource.setEnvironment(environment);
PropertiesUtil.getProperties().addPropertySource(Log4J2LoggingSystem.propertySource);
}
Expand All @@ -226,21 +232,6 @@ public void initialize(LoggingInitializationContext initializationContext, Strin
markAsInitialized(loggerContext);
}

/**
* Reset the stream used by the fallback listener to the current system out. This
* allows the fallback listener to work with any captured output streams in a similar
* way to the {@code follow} attribute of the {@code Console} appender.
* @param statusLogger the status logger to update
*/
private void resetFallbackListenerStream(StatusLogger statusLogger) {
try {
statusLogger.getFallbackListener().setStream(System.out);
}
catch (NoSuchMethodError ex) {
// Ignore for older versions of Log4J
}
}

@Override
protected void loadDefaults(LoggingInitializationContext initializationContext, LogFile logFile) {
String location = getPackagedConfigFile((logFile != null) ? "log4j2-file.xml" : "log4j2.xml");
Expand Down Expand Up @@ -454,9 +445,14 @@ public void cleanUp() {
super.cleanUp();
LoggerContext loggerContext = getLoggerContext();
markAsUninitialized(loggerContext);
StatusConsoleListener listener = (StatusConsoleListener) getLoggerContext().getObject(STATUS_LISTENER_KEY);
if (listener != null) {
StatusLogger.getLogger().removeListener(listener);
loggerContext.removeObject(STATUS_LISTENER_KEY);
}
loggerContext.getConfiguration().removeFilter(FILTER);
Log4J2LoggingSystem.propertySource.setEnvironment(null);
getLoggerContext().removeObject(ENVIRONMENT_KEY);
loggerContext.removeObject(ENVIRONMENT_KEY);
}

private LoggerConfig getLogger(String name) {
Expand Down
40 changes: 39 additions & 1 deletion ...-boot/src/test/java/org/springframework/boot/logging/log4j2/Log4J2LoggingSystemTests.java
View file
Open in desktop
Original file line number Diff line number Diff line change
@@ -1,5 +1,5 @@
/*
* Copyright 2012-2024 the original author or authors.
* 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.
Expand Down Expand Up @@ -41,6 +41,8 @@
import org.apache.logging.log4j.core.config.plugins.util.PluginRegistry;
import org.apache.logging.log4j.core.util.ShutdownCallbackRegistry;
import org.apache.logging.log4j.jul.Log4jBridgeHandler;
import org.apache.logging.log4j.status.StatusListener;
import org.apache.logging.log4j.status.StatusLogger;
import org.apache.logging.log4j.util.PropertiesUtil;
import org.junit.jupiter.api.AfterEach;
import org.junit.jupiter.api.BeforeEach;
Expand Down Expand Up @@ -469,6 +471,42 @@ void initializeAttachesEnvironmentToLoggerContext() {
assertThat(environment).isSameAs(this.environment);
}

@Test
void initializeRegisterStatusListenerAndAttachToLoggerContext() {
this.loggingSystem.beforeInitialize();
this.loggingSystem.initialize(this.initializationContext, null, null);
LoggerContext loggerContext = (LoggerContext) LogManager.getContext(false);
StatusListener statusListener = (StatusListener) loggerContext
.getObject(Log4J2LoggingSystem.STATUS_LISTENER_KEY);
assertThat(statusListener).isNotNull();
assertThat(StatusLogger.getLogger().getListeners()).contains(statusListener);
}

@Test
void statusListenerIsUpdatedUponReinitialization() {
this.loggingSystem.beforeInitialize();
this.loggingSystem.initialize(this.initializationContext, null, null);
// listener should be registered
LoggerContext loggerContext = (LoggerContext) LogManager.getContext(false);
StatusListener statusListener = (StatusListener) loggerContext
.getObject(Log4J2LoggingSystem.STATUS_LISTENER_KEY);
assertThat(statusListener).isNotNull();
assertThat(StatusLogger.getLogger().getListeners()).contains(statusListener);

this.loggingSystem.cleanUp();
// listener should be removed from context and StatusLogger
assertThat(StatusLogger.getLogger().getListeners()).doesNotContain(statusListener);
assertThat(loggerContext.getObject(Log4J2LoggingSystem.STATUS_LISTENER_KEY)).isNull();

// a new listener should be registered
this.loggingSystem.beforeInitialize();
this.loggingSystem.initialize(this.initializationContext, null, null);
StatusListener statusListener1 = (StatusListener) loggerContext
.getObject(Log4J2LoggingSystem.STATUS_LISTENER_KEY);
assertThat(statusListener1).isNotNull();
assertThat(StatusLogger.getLogger().getListeners()).contains(statusListener1);
}

@Test
void initializeAddsSpringEnvironmentPropertySource() {
this.environment.setProperty("spring", "boot");
Expand Down