Package org.apache.logging.log4j.core

Class LoggerContext

java.lang.Object
org.apache.logging.log4j.core.AbstractLifeCycle
org.apache.logging.log4j.core.LoggerContext
All Implemented Interfaces:
AutoCloseable, ConfigurationListener, LifeCycle, LifeCycle2, LoggerContext, LoggerContextShutdownEnabled, Terminable
Direct Known Subclasses:
AsyncLoggerContext
public class LoggerContext extends AbstractLifeCycle implements LoggerContext, AutoCloseable, Terminable, ConfigurationListener, LoggerContextShutdownEnabled
The LoggerContext is the anchor for the logging system. It maintains a list of all the loggers requested by applications and a reference to the Configuration. The Configuration will contain the configured loggers, appenders, filters, etc and will be atomically updated whenever a reconfigure occurs.

  • Field Details

    • PROPERTY_CONFIG

      public static final String PROPERTY_CONFIG
      Property name of the property change event fired if the configuration is changed.
      See Also:

  • Constructor Details

    • LoggerContext

      public LoggerContext(String name)
      Constructor taking only a name.
      Parameters:
      name - The context name.

    • LoggerContext

      public LoggerContext(String name, Object externalContext)
      Constructor taking a name and a reference to an external context.
      Parameters:
      name - The context name.
      externalContext - The external context.

    • LoggerContext

      public LoggerContext(String name, Object externalContext, URI configLocn)
      Constructor taking a name, external context and a configuration URI.
      Parameters:
      name - The context name.
      externalContext - The external context.
      configLocn - The location of the configuration as a URI.

    • LoggerContext

      public LoggerContext(String name, Object externalContext, String configLocn)
      Constructor taking a name external context and a configuration location String. The location must be resolvable to a File.
      Parameters:
      name - The configuration location.
      externalContext - The external context.
      configLocn - The configuration location.

  • Method Details

    • addShutdownListener

      public void addShutdownListener(LoggerContextShutdownAware listener)
      Specified by:
      addShutdownListener in interface LoggerContextShutdownEnabled

    • getListeners

      public List<LoggerContextShutdownAware> getListeners()
      Specified by:
      getListeners in interface LoggerContextShutdownEnabled

    • getContext

      public static LoggerContext getContext()
      Returns the current LoggerContext.

      Avoids the type cast for: 

       (LoggerContext) LogManager.getContext();

      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.
      See Also:

    • getContext

      public static LoggerContext getContext(boolean currentContext)
      Returns a LoggerContext.

      Avoids the type cast for: 

       (LoggerContext) LogManager.getContext(currentContext);
      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.
      See Also:

    • getContext

      public static LoggerContext getContext(ClassLoader loader, boolean currentContext, URI configLocation)
      Returns a LoggerContext.

      Avoids the type cast for: 

       (LoggerContext) LogManager.getContext(loader, currentContext, configLocation);
      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.
      See Also:

    • start

      public void start()
      Starts the context using the configuration specified by getConfigLocation().

      If the configuration location is null, Log4j will search for a configuration file using the default classpath resources. For details on the search order and supported formats, see the Log4j 2 Configuration File Location documentation.

      Specified by:
      start in interface LifeCycle
      Overrides:
      start in class AbstractLifeCycle

    • start

      public void start(Configuration config)
      Starts the context using a specific configuration.

      Warning: For backward compatibility, especially with Spring Boot, if the context is already started, this method will fall back to reconfigure(Configuration). This behavior is maintained for legacy integrations and may change in future major versions. New code should not rely on this fallback.

      Parameters:
      config - The new Configuration to use for this context

    • close

      public void close()
      Specified by:
      close in interface AutoCloseable

    • terminate

      public void terminate()
      Specified by:
      terminate in interface Terminable

    • stop

      public boolean stop(long timeout, TimeUnit timeUnit)
      Blocks until all Log4j tasks have completed execution after a shutdown request and all appenders have shut down, or the timeout occurs, or the current thread is interrupted, whichever happens first.

      Not all appenders will honor this, it is a hint and not an absolute guarantee that the this method not block longer. Setting timeout too low increase the risk of losing outstanding log events not yet written to the final destination.

      Log4j can start threads to perform certain actions like file rollovers, calling this method with a positive timeout will block until the rollover thread is done.

      Specified by:
      stop in interface LifeCycle2
      Overrides:
      stop in class AbstractLifeCycle
      Parameters:
      timeout - the maximum time to wait, or 0 which mean that each apppender uses its default timeout, and don't wait for background tasks
      timeUnit - the time unit of the timeout argument
      Returns:
      true if the logger context terminated and false if the timeout elapsed before termination.
      Since:
      2.7

    • getName

      public String getName()
      Gets the name.
      Returns:
      the name.

    • getRootLogger

      public Logger getRootLogger()
      Gets the root logger.
      Returns:
      the root logger.

    • setName

      public void setName(String name)
      Sets the name.
      Parameters:
      name - the new LoggerContext name
      Throws:
      NullPointerException - if the specified name is null

    • getObject

      public Object getObject(String key)
      Specified by:
      getObject in interface LoggerContext

    • putObject

      public Object putObject(String key, Object value)
      Specified by:
      putObject in interface LoggerContext

    • putObjectIfAbsent

      public Object putObjectIfAbsent(String key, Object value)
      Specified by:
      putObjectIfAbsent in interface LoggerContext

    • removeObject

      public Object removeObject(String key)
      Specified by:
      removeObject in interface LoggerContext

    • removeObject

      public boolean removeObject(String key, Object value)
      Specified by:
      removeObject in interface LoggerContext

    • setExternalContext

      public void setExternalContext(Object context)
      Sets the external context.
      Parameters:
      context - The external context.

    • getExternalContext

      public Object getExternalContext()
      Returns the external context.
      Specified by:
      getExternalContext in interface LoggerContext
      Returns:
      The external context.

    • getLogger

      public Logger getLogger(String name)
      Gets a Logger from the Context.
      Specified by:
      getLogger in interface LoggerContext
      Parameters:
      name - The name of the Logger to return.
      Returns:
      The Logger.

    • getLoggers

      public Collection<Logger> getLoggers()
      Gets a collection of the current loggers.

      Whether this collection is a copy of the underlying collection or not is undefined. Therefore, modify this collection at your own risk.

      Returns:
      a collection of the current loggers.

    • getLogger

      public Logger getLogger(String name, @Nullable MessageFactory messageFactory)
      Obtains a logger from the context.
      Specified by:
      getLogger in interface LoggerContext
      Parameters:
      name - a logger name
      messageFactory - a message factory to associate the logger with
      Returns:
      a logger matching the given name and message factory

    • getLoggerRegistry

      @Deprecated public LoggerRegistry<Logger> getLoggerRegistry()
      Deprecated.
      since 2.25.0 without a replacement.
      Gets the LoggerRegistry.
      Specified by:
      getLoggerRegistry in interface LoggerContext
      Returns:
      the LoggerRegistry.
      Since:
      2.17.2

    • hasLogger

      public boolean hasLogger(String name)
      Determines if the specified Logger exists.
      Specified by:
      hasLogger in interface LoggerContext
      Parameters:
      name - The Logger name to search for.
      Returns:
      True if the Logger exists, false otherwise.

    • hasLogger

      public boolean hasLogger(String name, @Nullable MessageFactory messageFactory)
      Determines if the specified Logger exists.
      Specified by:
      hasLogger in interface LoggerContext
      Parameters:
      name - The Logger name to search for.
      Returns:
      True if the Logger exists, false otherwise.

    • hasLogger

      public boolean hasLogger(String name, Class<? extends MessageFactory> messageFactoryClass)
      Determines if the specified Logger exists.
      Specified by:
      hasLogger in interface LoggerContext
      Parameters:
      name - The Logger name to search for.
      Returns:
      True if the Logger exists, false otherwise.

    • getConfiguration

      public Configuration getConfiguration()
      Returns the current Configuration. The Configuration will be replaced when a reconfigure occurs.
      Returns:
      The current Configuration, never null, but may be NullConfiguration.

    • addFilter

      public void addFilter(Filter filter)
      Adds a Filter to the Configuration. Filters that are added through the API will be lost when a reconfigure occurs.
      Parameters:
      filter - The Filter to add.

    • removeFilter

      public void removeFilter(Filter filter)
      Removes a Filter from the current Configuration.
      Parameters:
      filter - The Filter to remove.

    • setConfiguration

      public Configuration setConfiguration(Configuration config)
      Sets the Configuration to be used.
      Parameters:
      config - The new Configuration.
      Returns:
      The previous Configuration.

    • addPropertyChangeListener

      public void addPropertyChangeListener(PropertyChangeListener listener)

    • removePropertyChangeListener

      public void removePropertyChangeListener(PropertyChangeListener listener)

    • getConfigLocation

      public URI getConfigLocation()
      Returns the initial configuration location or null. The returned value may not be the location of the current configuration. Use getConfiguration().getConfigurationSource().getLocation() to get the actual source of the current configuration.
      Returns:
      the initial configuration location or null

    • setConfigLocation

      public void setConfigLocation(URI configLocation)
      Sets the configLocation to the specified value and reconfigures this context.
      Parameters:
      configLocation - the location of the new configuration

    • reconfigure

      public void reconfigure()
      Reconfigures the context. Log4j does not remove Loggers during a reconfiguration. Log4j will create new LoggerConfig objects and Log4j will point the Loggers at the new LoggerConfigs. Log4j will free the old LoggerConfig, along with old Appenders and Filters.

    • reconfigure

      public void reconfigure(Configuration configuration)

    • updateLoggers

      public void updateLoggers()
      Causes all Loggers to be updated against the current Configuration.

    • updateLoggers

      public void updateLoggers(Configuration config)
      Causes all Logger to be updated against the specified Configuration.
      Parameters:
      config - The Configuration.

    • onChange

      public void onChange(Reconfigurable reconfigurable)
      Causes a reconfiguration to take place when the underlying configuration file changes.
      Specified by:
      onChange in interface ConfigurationListener
      Parameters:
      reconfigurable - The Configuration that can be reconfigured.

    • newInstance

      protected Logger newInstance(LoggerContext context, String name, MessageFactory messageFactory)
      Callback to create a new logger.
      Parameters:
      context - The LoggerContext this logger is associated with, never null.
      messageFactory - The message factory to be used, never null.
      name - The logger name, never null.
      Returns:
      A new logger instance.