java.lang.ClassNotFoundException: org.apache.log4j

问题:

I'm trying to use hibernate 3.5.1 final in a swing application and here are the jars I'm using:

• hibernate-core-3.5.1-Final
• hibernate-entitymanager-3.5.1-Final
• hibernate-jpa-2.0-api-1.0.0.Final
• hibernate-annotations-3.5.1-Final
• hibernate-commons-annotations-3.2.0.Final
• dom4j-1.6.1
• slf4j-api-1.6.4
• slf4j-log4j12-1.6.4

When I try to run the application, I get the following error:

Failed to instantiate SLF4J LoggerFactory
Reported exception:
java.lang.NoClassDefFoundError: org/apache/log4j/Level
    at org.slf4j.LoggerFactory.bind(LoggerFactory.java:128)
    at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:108)
    at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:279)
    at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:252)
    at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:265)
    at org.hibernate.cfg.Configuration.<clinit>(Configuration.java:165)
    at org.hibernate.ejb.Ejb3Configuration.<clinit>(Ejb3Configuration.java:127)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:54)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:48)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:32)
    at com.xeno.xecamp.desktopManagement.Main.main(Main.java:16)
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Level
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:248)
    ... 11 more
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/log4j/Level
    at org.slf4j.LoggerFactory.bind(LoggerFactory.java:128)
    at org.slf4j.LoggerFactory.performInitialization(LoggerFactory.java:108)
    at org.slf4j.LoggerFactory.getILoggerFactory(LoggerFactory.java:279)
    at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:252)
    at org.slf4j.LoggerFactory.getLogger(LoggerFactory.java:265)
    at org.hibernate.cfg.Configuration.<clinit>(Configuration.java:165)
    at org.hibernate.ejb.Ejb3Configuration.<clinit>(Ejb3Configuration.java:127)
    at org.hibernate.ejb.HibernatePersistence.createEntityManagerFactory(HibernatePersistence.java:54)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:48)
    at javax.persistence.Persistence.createEntityManagerFactory(Persistence.java:32)
    at com.xeno.xecamp.desktopManagement.Main.main(Main.java:16)
Caused by: java.lang.ClassNotFoundException: org.apache.log4j.Level
    at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:307)
    at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
    at java.lang.ClassLoader.loadClass(ClassLoader.java:248)

回答1:

You also need to include the Log4J JAR file in the classpath.

Note that slf4j-log4j12-1.6.4.jar is only an adapter to make it possible to use Log4J via the SLF4J API. It does not contain the actual implementation of Log4J.

回答2:

You need to download log4j and add in your classpath.

回答3:

In my environment, I just added the two files to class path. And is work fine.

slf4j-jdk14-1.7.25.jar
slf4j-api-1.7.25.jar