Class Log

java.lang.Object
org.jfree.util.Log

public class Log extends Object
A simple logging facility. Create a class implementing the LogTarget interface to use this feature.
Author:
Thomas Morgner
  • Nested Class Summary

    Nested Classes
    Modifier and Type
    Class
    Description
    static class 
    A simple message class.
  • Constructor Summary

    Constructors
    Modifier
    Constructor
    Description
    protected
    Log()
    Creates a new Log instance.
  • Method Summary

    Modifier and Type
    Method
    Description
    void
    Adds a log target to this facility.
    static LogContext
    Creates a log context.
    static LogContext
    Creates a log context.
    static void
    debug(Object message)
    A convenience method for logging a 'debug' message.
    static void
    debug(Object message, Exception e)
    A convenience method for logging a 'debug' message.
    protected static void
    Redefines or clears the currently used log instance.
    protected void
    doLog(int level, Object message)
    Logs a message to the main log stream.
    protected void
    doLog(int level, Object message, Exception e)
    Logs a message to the main log stream.
    static void
    error(Object message)
    A convenience method for logging an 'error' message.
    static void
    error(Object message, Exception e)
    A convenience method for logging an 'error' message.
    int
    Returns the currently defined debug level.
    static Log
    Returns the singleton Log instance.
    Returns the registered logtargets.
    static void
    info(Object message)
    A convenience method for logging an 'info' message.
    static void
    info(Object message, Exception e)
    A convenience method for logging an 'info' message.
    void
    Initializes the logging system.
    protected LogContext
    Creates a log context.
    static boolean
    Returns true, if the log level allows debug messages to be printed.
    static boolean
    Returns true, if the log level allows error messages to be printed.
    static boolean
    Returns true, if the log level allows informational messages to be printed.
    static boolean
    Returns true, if the log level allows warning messages to be printed.
    static void
    log(int level, Object message)
    Logs a message to the main log stream.
    static void
    log(int level, Object message, Exception e)
    Logs a message to the main log stream.
    void
    Removes a log target from this facility.
    void
    Replaces all log targets by the given target.
    protected void
    setDebuglevel(int debuglevel)
    Defines the debug level for the log system.
    static void
    warn(Object message)
    A convenience method for logging a 'warning' message.
    static void
    warn(Object message, Exception e)
    A convenience method for logging a 'warning' message.

    Methods inherited from class java.lang.Object

    clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait
  • Constructor Details

    • Log

      protected Log()
      Creates a new Log instance. The Log is used to manage the log targets.
  • Method Details

    • getInstance

      public static Log getInstance()
      Returns the singleton Log instance. A new instance is created if necessary.
      Returns:
      the singleton instance.
    • defineLog

      protected static void defineLog(Log log)
      Redefines or clears the currently used log instance.
      Parameters:
      log - the new log instance or null, to return to the default implementation.
    • getDebuglevel

      public int getDebuglevel()
      Returns the currently defined debug level. The higher the level, the more details are printed.
      Returns:
      the debug level.
    • setDebuglevel

      protected void setDebuglevel(int debuglevel)
      Defines the debug level for the log system.
      Parameters:
      debuglevel - the new debug level
      See Also:
    • addTarget

      public void addTarget(LogTarget target)
      Adds a log target to this facility. Log targets get informed, via the LogTarget interface, whenever a message is logged with this class.
      Parameters:
      target - the target.
    • removeTarget

      public void removeTarget(LogTarget target)
      Removes a log target from this facility.
      Parameters:
      target - the target to remove.
    • getTargets

      public LogTarget[] getTargets()
      Returns the registered logtargets.
      Returns:
      the logtargets.
    • replaceTargets

      public void replaceTargets(LogTarget target)
      Replaces all log targets by the given target.
      Parameters:
      target - the new and only logtarget.
    • debug

      public static void debug(Object message)
      A convenience method for logging a 'debug' message.
      Parameters:
      message - the message.
    • debug

      public static void debug(Object message, Exception e)
      A convenience method for logging a 'debug' message.
      Parameters:
      message - the message.
      e - the exception.
    • info

      public static void info(Object message)
      A convenience method for logging an 'info' message.
      Parameters:
      message - the message.
    • info

      public static void info(Object message, Exception e)
      A convenience method for logging an 'info' message.
      Parameters:
      message - the message.
      e - the exception.
    • warn

      public static void warn(Object message)
      A convenience method for logging a 'warning' message.
      Parameters:
      message - the message.
    • warn

      public static void warn(Object message, Exception e)
      A convenience method for logging a 'warning' message.
      Parameters:
      message - the message.
      e - the exception.
    • error

      public static void error(Object message)
      A convenience method for logging an 'error' message.
      Parameters:
      message - the message.
    • error

      public static void error(Object message, Exception e)
      A convenience method for logging an 'error' message.
      Parameters:
      message - the message.
      e - the exception.
    • doLog

      protected void doLog(int level, Object message)
      Logs a message to the main log stream. All attached log targets will also receive this message. If the given log-level is higher than the given debug-level in the main config file, no logging will be done.
      Parameters:
      level - log level of the message.
      message - text to be logged.
    • log

      public static void log(int level, Object message)
      Logs a message to the main log stream. All attached log targets will also receive this message. If the given log-level is higher than the given debug-level in the main config file, no logging will be done.
      Parameters:
      level - log level of the message.
      message - text to be logged.
    • log

      public static void log(int level, Object message, Exception e)
      Logs a message to the main log stream. All attached logTargets will also receive this message. If the given log-level is higher than the given debug-level in the main config file, no logging will be done.

      The exception's stacktrace will be appended to the log-stream

      Parameters:
      level - log level of the message.
      message - text to be logged.
      e - the exception, which should be logged.
    • doLog

      protected void doLog(int level, Object message, Exception e)
      Logs a message to the main log stream. All attached logTargets will also receive this message. If the given log-level is higher than the given debug-level in the main config file, no logging will be done.

      The exception's stacktrace will be appended to the log-stream

      Parameters:
      level - log level of the message.
      message - text to be logged.
      e - the exception, which should be logged.
    • init

      public void init()
      Initializes the logging system. Implementors should override this method to supply their own log configuration.
    • isDebugEnabled

      public static boolean isDebugEnabled()
      Returns true, if the log level allows debug messages to be printed.
      Returns:
      true, if messages with an log level of DEBUG are allowed.
    • isInfoEnabled

      public static boolean isInfoEnabled()
      Returns true, if the log level allows informational messages to be printed.
      Returns:
      true, if messages with an log level of INFO are allowed.
    • isWarningEnabled

      public static boolean isWarningEnabled()
      Returns true, if the log level allows warning messages to be printed.
      Returns:
      true, if messages with an log level of WARN are allowed.
    • isErrorEnabled

      public static boolean isErrorEnabled()
      Returns true, if the log level allows error messages to be printed.
      Returns:
      true, if messages with an log level of ERROR are allowed.
    • createContext

      public static LogContext createContext(Class context)
      Creates a log context.
      Parameters:
      context - the class (null not permitted).
      Returns:
      A log context.
    • createContext

      public static LogContext createContext(String context)
      Creates a log context.
      Parameters:
      context - the label for the context.
      Returns:
      A log context.
    • internalCreateContext

      Creates a log context.
      Parameters:
      context - the name of the logging context (a common prefix).
      Returns:
      A log context.