Class Logger

All Implemented Interfaces:
AppenderAttachable
Direct Known Subclasses:
NOPLogger, RootCategory, RootLogger

public class Logger extends Category
This is the central class in the log4j package. Most logging operations, except configuration, are done through this class.
Since:
log4j 1.2
Author:
Ceki Gülcü
  • Constructor Details

    • Logger

      protected Logger(String name)
  • Method Details

    • getLogger

      public static Logger getLogger(String name)
      Retrieve a logger named according to the value of the name parameter. If the named logger already exists, then the existing instance will be returned. Otherwise, a new instance is created.

      By default, loggers do not have a set level but inherit it from their neareast ancestor with a set level. This is one of the central features of log4j.

      Parameters:
      name - The name of the logger to retrieve.
    • getLogger

      public static Logger getLogger(Class clazz)
      Shorthand for getLogger(clazz.getName()).
      Parameters:
      clazz - The name of clazz will be used as the name of the logger to retrieve. See getLogger(String) for more detailed information.
    • getRootLogger

      public static Logger getRootLogger()
      Return the root logger for the current logger repository.

      The Logger.getName() method for the root logger always returns string value: "root". However, calling Logger.getLogger("root") does not retrieve the root logger but a logger just under root named "root".

      In other words, calling this method is the only way to retrieve the root logger.

    • getLogger

      public static Logger getLogger(String name, LoggerFactory factory)
      Like getLogger(String) except that the type of logger instantiated depends on the type returned by the LoggerFactory.makeNewLoggerInstance(java.lang.String) method of the factory parameter.

      This method is intended to be used by sub-classes.

      Parameters:
      name - The name of the logger to retrieve.
      factory - A LoggerFactory implementation that will actually create a new Instance.
      Since:
      0.8.5
    • trace

      public void trace(Object message)
      Log a message object with the TRACE level.
      Parameters:
      message - the message object to log.
      Since:
      1.2.12
      See Also:
    • trace

      public void trace(Object message, Throwable t)
      Log a message object with the TRACE level including the stack trace of the Throwablet passed as parameter.

      See Category.debug(Object) form for more detailed information.

      Parameters:
      message - the message object to log.
      t - the exception to log, including its stack trace.
      Since:
      1.2.12
    • isTraceEnabled

      public boolean isTraceEnabled()
      Check whether this category is enabled for the TRACE Level.
      Returns:
      boolean - true if this category is enabled for level TRACE, false otherwise.
      Since:
      1.2.12