Package org.apache.logging.log4j

Class LogManager

java.lang.Object
org.apache.logging.log4j.LogManager
public class LogManager extends Object
The anchor point for the Log4j logging system. The most common usage of this class is to obtain a named Logger. The method getLogger() is provided as the most convenient way to obtain a named Logger based on the calling class name. This class also provides method for obtaining named Loggers that use String.format(String, Object...) style messages instead of the default type of parameterized messages. These are obtained through the getFormatterLogger(Class) family of methods. Other service provider methods are given through the getContext() and getFactory() family of methods; these methods are not normally useful for typical usage of Log4j.

  • Field Details

  • Constructor Details

    • LogManager

      protected LogManager()
      Prevents instantiation

  • Method Details

    • exists

      public static boolean exists(String name)
      Detects if a Logger with the specified name exists. This is a convenience method for porting from version 1.
      Parameters:
      name - The Logger name to search for.
      Returns:
      true if the Logger exists, false otherwise.
      See Also:

    • getContext

      public static LoggerContext getContext()
      Returns the current LoggerContext.

      WARNING - The LoggerContext returned by this method may not be the LoggerContext used to create a Logger for the calling class.

      Returns:
      The current LoggerContext.

    • getContext

      public static LoggerContext getContext(boolean currentContext)
      Returns a LoggerContext.
      Parameters:
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      Returns:
      a LoggerContext.

    • getContext

      public static LoggerContext getContext(ClassLoader loader, boolean currentContext)
      Returns a LoggerContext.
      Parameters:
      loader - The ClassLoader for the context. If null the context will attempt to determine the appropriate ClassLoader.
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      Returns:
      a LoggerContext.

    • getContext

      public static LoggerContext getContext(ClassLoader loader, boolean currentContext, Object externalContext)
      Returns a LoggerContext.
      Parameters:
      loader - The ClassLoader for the context. If null the context will attempt to determine the appropriate ClassLoader.
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      externalContext - An external context (such as a ServletContext) to be associated with the LoggerContext.
      Returns:
      a LoggerContext.

    • getContext

      public static LoggerContext getContext(ClassLoader loader, boolean currentContext, URI configLocation)
      Returns a LoggerContext.
      Parameters:
      loader - The ClassLoader for the context. If null the context will attempt to determine the appropriate ClassLoader.
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      configLocation - The URI for the configuration to use.
      Returns:
      a LoggerContext.

    • getContext

      public static LoggerContext getContext(ClassLoader loader, boolean currentContext, Object externalContext, URI configLocation)
      Returns a LoggerContext.
      Parameters:
      loader - The ClassLoader for the context. If null the context will attempt to determine the appropriate ClassLoader.
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      externalContext - An external context (such as a ServletContext) to be associated with the LoggerContext.
      configLocation - The URI for the configuration to use.
      Returns:
      a LoggerContext.

    • getContext

      public static LoggerContext getContext(ClassLoader loader, boolean currentContext, Object externalContext, URI configLocation, String name)
      Returns a LoggerContext.
      Parameters:
      loader - The ClassLoader for the context. If null the context will attempt to determine the appropriate ClassLoader.
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      externalContext - An external context (such as a ServletContext) to be associated with the LoggerContext.
      configLocation - The URI for the configuration to use.
      name - The LoggerContext name.
      Returns:
      a LoggerContext.

    • getContext

      protected static LoggerContext getContext(String fqcn, boolean currentContext)
      Returns a LoggerContext
      Parameters:
      fqcn - The fully qualified class name of the Class that this method is a member of.
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      Returns:
      a LoggerContext.

    • getContext

      protected static LoggerContext getContext(String fqcn, ClassLoader loader, boolean currentContext)
      Returns a LoggerContext
      Parameters:
      fqcn - The fully qualified class name of the Class that this method is a member of.
      loader - The ClassLoader for the context. If null the context will attempt to determine the appropriate ClassLoader.
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      Returns:
      a LoggerContext.

    • getContext

      protected static LoggerContext getContext(String fqcn, ClassLoader loader, boolean currentContext, URI configLocation, String name)
      Returns a LoggerContext
      Parameters:
      fqcn - The fully qualified class name of the Class that this method is a member of.
      loader - The ClassLoader for the context. If null the context will attempt to determine the appropriate ClassLoader.
      currentContext - if false the LoggerContext appropriate for the caller of this method is returned. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be returned and if the caller is a class in the container's classpath then a different LoggerContext may be returned. If true then only a single LoggerContext will be returned.
      configLocation - The URI for the configuration to use.
      name - The LoggerContext name.
      Returns:
      a LoggerContext.
      Since:
      2.9.1

    • shutdown

      public static void shutdown()
      Shutdown using the LoggerContext appropriate for the caller of this method. This is equivalent to calling LogManager.shutdown(false).

      This call is synchronous and will block until shut down is complete. This may include flushing pending log events over network connections.

      Since:
      2.6

    • shutdown

      public static void shutdown(boolean currentContext)
      Shutdown the logging system if the logging system supports it. This is equivalent to calling LogManager.shutdown(LogManager.getContext(currentContext)).

      This call is synchronous and will block until shut down is complete. This may include flushing pending log events over network connections.

      Parameters:
      currentContext - if true a default LoggerContext (may not be the LoggerContext used to create a Logger for the calling class) will be used. If false the LoggerContext appropriate for the caller of this method is used. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be used and if the caller is a class in the container's classpath then a different LoggerContext may be used.
      Since:
      2.6

    • shutdown

      public static void shutdown(boolean currentContext, boolean allContexts)
      Shutdown the logging system if the logging system supports it. This is equivalent to calling LogManager.shutdown(LogManager.getContext(currentContext)).

      This call is synchronous and will block until shut down is complete. This may include flushing pending log events over network connections.

      Parameters:
      currentContext - if true a default LoggerContext (may not be the LoggerContext used to create a Logger for the calling class) will be used. If false the LoggerContext appropriate for the caller of this method is used. For example, in a web application if the caller is a class in WEB-INF/lib then one LoggerContext may be used and if the caller is a class in the container's classpath then a different LoggerContext may be used.
      allContexts - if true all LoggerContexts that can be located will be shutdown.
      Since:
      2.13.0

    • shutdown

      public static void shutdown(LoggerContext context)
      Shutdown the logging system if the logging system supports it.

      This call is synchronous and will block until shut down is complete. This may include flushing pending log events over network connections.

      Parameters:
      context - the LoggerContext.
      Since:
      2.6

    • getFactory

      public static LoggerContextFactory getFactory()
      Returns the current LoggerContextFactory.
      Returns:
      The LoggerContextFactory.

    • setFactory

      public static void setFactory(LoggerContextFactory factory)
      Sets the current LoggerContextFactory to use. Normally, the appropriate LoggerContextFactory is created at startup, but in certain environments, a LoggerContextFactory implementation may not be available at this point. Thus, an alternative LoggerContextFactory can be set at runtime.

      Note that any Logger or LoggerContext objects already created will still be valid, but they will no longer be accessible through LogManager. Thus, it is a bad idea to use this method without a good reason! Generally, this method should be used only during startup before any code starts caching Logger objects.

      Parameters:
      factory - the LoggerContextFactory to use.

    • getFormatterLogger

      public static Logger getFormatterLogger()
      Returns a formatter Logger using the fully qualified name of the calling Class as the Logger name.

      This logger lets you use a Formatter string in the message to format parameters.

      Returns:
      The Logger for the calling class.
      Throws:
      UnsupportedOperationException - if the calling class cannot be determined.
      Since:
      2.4

    • getFormatterLogger

      public static Logger getFormatterLogger(Class<?> clazz)
      Returns a formatter Logger using the fully qualified name of the Class as the Logger name.

      This logger let you use a Formatter string in the message to format parameters.

      Short-hand for getLogger(clazz, StringFormatterMessageFactory.INSTANCE)

      Parameters:
      clazz - The Class whose name should be used as the Logger name.
      Returns:
      The Logger, created with a StringFormatterMessageFactory
      Throws:
      UnsupportedOperationException - if clazz is null and the calling class cannot be determined.
      See Also:

    • getFormatterLogger

      public static Logger getFormatterLogger(Object value)
      Returns a formatter Logger using the fully qualified name of the value's Class as the Logger name.

      This logger let you use a Formatter string in the message to format parameters.

      Short-hand for getLogger(value, StringFormatterMessageFactory.INSTANCE)

      Parameters:
      value - The value whose class name should be used as the Logger name.
      Returns:
      The Logger, created with a StringFormatterMessageFactory
      Throws:
      UnsupportedOperationException - if value is null and the calling class cannot be determined.
      See Also:

    • getFormatterLogger

      public static Logger getFormatterLogger(String name)
      Returns a formatter Logger with the specified name.

      This logger let you use a Formatter string in the message to format parameters.

      Short-hand for getLogger(name, StringFormatterMessageFactory.INSTANCE)

      Parameters:
      name - The logger name. If null it will default to the name of the calling class.
      Returns:
      The Logger, created with a StringFormatterMessageFactory
      Throws:
      UnsupportedOperationException - if name is null and the calling class cannot be determined.
      See Also:

    • getLogger

      public static Logger getLogger()
      Returns a Logger with the name of the calling class.
      Returns:
      The Logger for the calling class.
      Throws:
      UnsupportedOperationException - if the calling class cannot be determined.

    • getLogger

      public static Logger getLogger(Class<?> clazz)
      Returns a Logger using the fully qualified name of the Class as the Logger name.
      Parameters:
      clazz - The Class whose name should be used as the Logger name. If null it will default to the calling class.
      Returns:
      The Logger.
      Throws:
      UnsupportedOperationException - if clazz is null and the calling class cannot be determined.

    • getLogger

      public static Logger getLogger(Class<?> clazz, MessageFactory messageFactory)
      Returns a Logger using the fully qualified name of the Class as the Logger name.
      Parameters:
      clazz - The Class whose name should be used as the Logger name. If null it will default to the calling class.
      messageFactory - The message factory is used only when creating a logger, subsequent use does not change the logger but will log a warning if mismatched.
      Returns:
      The Logger.
      Throws:
      UnsupportedOperationException - if clazz is null and the calling class cannot be determined.

    • getLogger

      public static Logger getLogger(MessageFactory messageFactory)
      Returns a Logger with the name of the calling class.
      Parameters:
      messageFactory - The message factory is used only when creating a logger, subsequent use does not change the logger but will log a warning if mismatched.
      Returns:
      The Logger for the calling class.
      Throws:
      UnsupportedOperationException - if the calling class cannot be determined.

    • getLogger

      public static Logger getLogger(Object value)
      Returns a Logger using the fully qualified class name of the value as the Logger name.
      Parameters:
      value - The value whose class name should be used as the Logger name. If null the name of the calling class will be used as the logger name.
      Returns:
      The Logger.
      Throws:
      UnsupportedOperationException - if value is null and the calling class cannot be determined.

    • getLogger

      public static Logger getLogger(Object value, MessageFactory messageFactory)
      Returns a Logger using the fully qualified class name of the value as the Logger name.
      Parameters:
      value - The value whose class name should be used as the Logger name. If null the name of the calling class will be used as the logger name.
      messageFactory - The message factory is used only when creating a logger, subsequent use does not change the logger but will log a warning if mismatched.
      Returns:
      The Logger.
      Throws:
      UnsupportedOperationException - if value is null and the calling class cannot be determined.

    • getLogger

      public static Logger getLogger(String name)
      Returns a Logger with the specified name.
      Parameters:
      name - The logger name. If null the name of the calling class will be used.
      Returns:
      The Logger.
      Throws:
      UnsupportedOperationException - if name is null and the calling class cannot be determined.

    • getLogger

      public static Logger getLogger(String name, MessageFactory messageFactory)
      Returns a Logger with the specified name.
      Parameters:
      name - The logger name. If null the name of the calling class will be used.
      messageFactory - The message factory is used only when creating a logger, subsequent use does not change the logger but will log a warning if mismatched.
      Returns:
      The Logger.
      Throws:
      UnsupportedOperationException - if name is null and the calling class cannot be determined.

    • getLogger

      protected static Logger getLogger(String fqcn, String name)
      Returns a Logger with the specified name.
      Parameters:
      fqcn - The fully qualified class name of the class that this method is a member of.
      name - The logger name.
      Returns:
      The Logger.

    • getRootLogger

      public static Logger getRootLogger()
      Returns the root logger.
      Returns:
      the root logger, named ROOT_LOGGER_NAME.