Apache commons logging where is the log file

Improve this question. I'm trying to write the output to a file that I can specify. So, that message inside log. When you say specify, do you mean specify dynamically from within the program? At this point all I am concerned about is hard-coding it into the above example. Add a comment. Active Oldest Votes. Improve this answer. Evgeniy Dorofeev Evgeniy Dorofeev k 27 27 gold badges silver badges bronze badges.

ConsoleAppender log4j. PatternLayout log4j. How would I do that inside the code? 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.

An exception that is thrown only if a suitable LogFactory or Log instance cannot be created by the corresponding factory methods. Overview This package provides an API for logging in server-based applications that can be used around a variety of different logging implementations, including prebuilt support for the following: Log4J version 1.

Each named Log instance is connected to a corresponding Log4J Logger. Each named Log instance is connected to a corresponding java. Logger instance. LogKit from Apache's Avalon project. Each named Log instance is connected to a corresponding LogKit Logger.

NoOpLog implementation that simply swallows all log output, for all named Log instances. SimpleLog implementation that writes all log output, for all named Log instances, to System. Quick Start Guide For those impatient to just get on with it, the following example illustrates the typical declaration and use of a logger that is named by convention after the calling class: import org. Configuring the Commons Logging Package Choosing a LogFactory Implementation From an application perspective, the first requirement is to retrieve an object reference to the LogFactory instance that will be used to create Log instances for this application.

This method implements the following discovery algorithm to select the name of the LogFactory implementation class this application wants to use: Check for a system property named org. Use the JDK 1. LogFactory whose first line is assumed to contain the desired class name. Look for a properties file named commons-logging. Home Documentation Development.

This document is for the new November 4. Refer to Logging 3. Sets the initial logging level of the root logger. Sets the log file to which log messages are written. If this property is empty or missing, log messages are written to System. Defines how the log file is rotated by schedule or by size and when to rotate. See the section Log File Rotation below for full details on log file rotation. The MessageFormat pattern to use for formatting log messages with the root logger.

Path for the Logback config file which would be used to configure logging. If the path is not absolute then it would be resolved against Sling Home. Boolean property to control packaging data support of Logback. See Packaging Data section of Logback for more details.

Number of lines from each log files to include while generating the dump in 'txt' mode. If set to -1 then whole file would be included. Maximum number of old rolled over files for each active file to be included while generating the dump as part of Status zip support. The directory, which is used to resolve relative path names against. If not specified it would map to sling.

Since 4. Sets the logging level of the loggers. This property should refer to the file name of a configured Log Writer see below. If no Log Writer is configured with the same file name an implicit Log Writer configuration with default configuration is created.

The java. MessageFormat pattern to use for formatting log messages with the root logger. This is a java. If the log call includes a Throwable, the stacktrace is just appended to the message regardless of the pattern. If set to false then logs from these loggers would not be sent to any appender attached higher in the hierarchy. At approximately