Where is commons logging.jar

You should add an exclusion for it like you have for spring-framework and spring-security. Stack Overflow for Teams — Collaborate and share knowledge with a private group. Create a free Team What is Teams? Collectives on Stack Overflow. Learn more. Cannot find commons logging class Ask Question. Asked 9 years, 3 months ago. Active 9 years, 3 months ago. Viewed 16k times. I'm getting this exception when trying to run my webapp: Exception sending context initialized event to listener instance of class org.

ContextLoaderListener java. ClassNotFoundException: org. LogFactory at org. If some more code is needed just tell and I'll provide.

ExceptionInInitializerError at org. IllegalStateException: org. LoggerFactory could not be successfully initialized. Improve this question. Add a comment. Active Oldest Votes. Improve this answer. Facing same issue. Where were tmp0 and tmp1? And how exactly do you recreate a workspace in eclipse? Do you mean create a new workspace?

Hm thats long ago. I can find a tmp0 folder here:. Ok, no prob. I had done some clean-up using mvn command line commands on an eclipse project which was using m2eclipse. Seems like m2eclipse and mvn commands do not work well together. Community Bot 1 1 1 silver badge. Duncan Jones Duncan Jones I can't find any dependency which has commons-logging as dependency.

So where does this commons-logging dependency come from? There's a good chance that it'll guess discover your preferred logging system and you won't need to do any configuration of JCL at all! Note, however, that if you have a particular preference then providing a simple commons-logging.

When no particular logging library is specified then JCL will silently ignore any logging library that it finds but cannot initialise and continue to look for other alternatives. This is a deliberate design decision; no application should fail to run because a "guessed" logging library cannot be used. To ensure an exception is reported when a particular logging library cannot be used, use one of the available JCL configuration mechanisms to force that library to be selected ie disable JCL's discovery process.

Specifying a particular Log implementation is very useful whether that is one provided by commons-logging or a user-defined one. Specifying a LogFactory implementation other than the default is a subject for advanced users only, so will not be addressed here.

The default LogFactory implementation uses the following discovery process to determine what type of Log implementation it should use the process terminates when the first positive match - in order - is found :. Configuration attributes can be set explicitly by java code, but they are more commonly set by placing a file named commons-logging.

When such a file exists, every entry in the properties file becomes an "attribute" of the LogFactory. When there is more than one such file in the classpath, releases of commons-logging prior to 1. From release 1. When multiple files have the same priority, the first one found is used. Defining this property in a commons-logging. Consult the JCL javadocs for details of the various Log implementations that ship with the component. The discovery process is also covered in more detail there.

JCL provides only a bridge for writing log messages. It does not and will not support any sort of configuration API for the underlying logging system. Configuration of the behavior of the JCL ultimately depends upon the logging toolkit being used.

Please consult the documentation for the chosen logging system. JCL is NOT responsible for initialisation, configuration or shutdown of the underlying logging library.

In these situations an application can simply use JCL and not depend directly on the API of the underlying logging system in any way. However if the logging library being used requires special initialisation, configuration or shutdown then some logging-library-specific code will be required in the application. JCL simply forwards logging method calls to the correct underlying implementation. When writing library code this issue is of course not relevant as the calling application is responsible for handling such issues.

Review the component documentation for guidelines on how commons-logging should be used in such components. Note that for application code, declaring the log member as "static" is more efficient as one Log object is created per class, and is recommended. However this is not safe to do for a class which may be deployed via a "shared" classloader in a servlet or j2ee container or similar environment. If the class may end up invoked with different thread-context-classloader values set then the member must not be declared static.

The use of "static" should therefore be avoided in code within any "library" type project. Messages are logged to a logger , such as log by invoking a method corresponding to priority. The org. Semantics for these methods are such that it is expected that the severity, from highest to lowest, of messages is ordered as above. Prior to release 1. If you are using such a release and have a Serializable class with a member that is of type Log then it is necessary to declare that member to be transient and to ensure that the value is restored on deserialization.

The recommended approach is to define a custom readObject method on the class which reinitializes that member. In release 1. This means that class members of type Log do not need to be declared transient; on deserialization the Log object will "rebind" to the same category for the same logging library.

Note that the same underlying logging library will be used on deserialization as was used in the original object, even if the application the object was deserialized into is using a different logging library.

Custom Log implementations not distributed with commons-logging may or may not be Serializable. If you wish your code to be compatible with any arbitrary log adapter then you should follow the advice given above for pre The commons-logging.

In most cases, including commons-logging. The commons-logging-api. However it does not include the wrapper Log implementations that require additional libraries such as Log4j , Avalon and Lumberjack.

This jar is intended for use by projects that recompile the commons-logging source using alternate java environments, and cannot compile against all of the optional libraries that the Apache release of commons-logging supports.

Because of the reduced dependencies of this jarfile, such projects should be able to create an equivalent of this library with fewer difficulties. This jar is also useful for build environments that automatically track dependencies, and thus have difficulty with the concept that the main commons-logging.

The commons-logging-adapters. As such, it cannot be used alone; either commons-logging. This library will not often be used; it is only intended for situations where a container has deployed commons-logging-api. In this situation, deploying the commons-logging. Deploying only the adapters avoids this problem. The general principles are fairly clear.

Enterprise practices are a bit more involved and it is not always as clear as to why they are important. Enterprise best-practice principles apply to middleware components and tooling that is expected to execute in an "Enterprise" level environment. These issues relate to Logging as Internationalization, and fault detection.

Enterprise requires more effort and planning, but are strongly encouraged if not required in production level systems. Code guards are typically used to guard code that only needs to execute in support of logging, that otherwise introduces undesirable runtime overhead in the general case logging disabled.

Examples are multiple parameters, or expressions e. Use the guard methods of the form log. Yes, the logging methods will perform the same check, but only after resolving parameters. It is important to ensure that log message are appropriate in content and severity. The following guidelines are suggested:. By default the message priority should be no lower than info. That is, by default debug message should not be seen in the logs.

Since any problems that result are going to be assigned to you, it's in your best interest to be prepared with the proactive tools necessary to demonstrate that your component works correctly, or at worst that the problem can be analyzed from your logs.

For this discussion, we must make a distinction between different types of exceptions based on what kind of boundaries they cross:. There is simply too much information in debug to be appropriate for day-to-day operations. If more control is desired for the level of detail of these 'enterprise' exceptions, then consider creating a special logger just for these exceptions:.

NLS internationalization involves looking up messages from a message file by a message key, and using that message for logging. There are various tools in Java, and provided by other components, for working with NLS messages. NLS enabled components are particularly appreciated that's an open-source-correct term for 'required by corporate end-users' :- for tooling and middleware components.

It is generally considered optional for debug and trace messages. Perhaps more direct support for internationalizing log messages can be introduced in a future or alternate version of the Log interface. The LogFactory discovery process see Configuration above is a fairly expensive operation, so JCL certainly should not perform it each time user code invokes:. Instead JCL caches the LogFactory implementation created as a result of the discovery process and uses the cached factory to return Log objects.

Since in J2EE and similar multi-classloader environments, the result of the discovery process can vary depending on the thread context classloader e. While this approach is efficient, it can lead to memory leaks if container implementors are not careful to call. If release is not called, a reference to the undeployed classloader and thus to all the classes loaded by it will be held in LogFactory 's static hashtable.

Beginning with JCL 1. This class is similar to java. WeakHashMap in that it holds a WeakReference to each key but a strong reference to each value , thus allowing classloaders to be GC'd even if LogFactory.