看https://github.com/jboss-logging/jboss-logging/blob/master/src/main/java/org/jboss/logging/LoggerProviders.java:
static final String LOGGING_PROVIDER_KEY = "org.jboss.logging.provider";
private static LoggerProvider findProvider() {
// Since the impl classes refer to the back-end frameworks directly, if this classloader can't find the target
// log classes, then it doesn't really matter if they're possibly available from the TCCL because we won't be
// able to find it anyway
final ClassLoader cl = LoggerProviders.class.getClassLoader();
try {
// Check the system property
final String loggerProvider = AccessController.doPrivileged(new PrivilegedAction<String>() {
public String run() {
return System.getProperty(LOGGING_PROVIDER_KEY);
}
});
if (loggerProvider != null) {
if ("jboss".equalsIgnoreCase(loggerProvider)) {
return tryJBossLogManager(cl);
} else if ("jdk".equalsIgnoreCase(loggerProvider)) {
return tryJDK();
} else if ("log4j".equalsIgnoreCase(loggerProvider)) {
return tryLog4j(cl);
} else if ("slf4j".equalsIgnoreCase(loggerProvider)) {
return trySlf4j();
}
}
} catch (Throwable t) {
}
try {
return tryJBossLogManager(cl);
} catch (Throwable t) {
// nope...
}
try {
return tryLog4j(cl);
} catch (Throwable t) {
// nope...
}
try {
// only use slf4j if Logback is in use
Class.forName("ch.qos.logback.classic.Logger", false, cl);
return trySlf4j();
} catch (Throwable t) {
// nope...
}
return tryJDK();
}
所以org.jboss.logging.provider 的可能值为：jboss、jdk、log4j、slf4j。
如果你没有设置org.jboss.logging.provider，它会尝试 jboss，然后是 log4j，然后是 slf4j（仅当使用 logback 时）并回退到 jdk。
我将slf4j 与logback-classic 一起使用：
<dependency>
<groupId>ch.qos.logback</groupId>
<artifactId>logback-classic</artifactId>
<version>1.0.13</version>
<scope>${logging.scope}</scope>
</dependency>
一切正常！
UPDATE一些用户在非常主要的App.java中使用：
static { //runs when the main class is loaded.
System.setProperty("org.jboss.logging.provider", "slf4j");
}
但对于基于容器的解决方案，这是行不通的。
更新 2 那些认为他们使用 SLF4J 为 jboss-logging 管理 Log4j 的人并非完全如此。 jboss-logging 直接用Log4j，不用SLF4J！