Interface Log

public interface Log
A simple logging interface abstracting logging APIs. In order to be instantiated successfully by LogFactory, classes that implement this interface must have a constructor that takes a single String parameter representing the "name" of this Log.

The six logging levels used by Log are (in order):

  1. trace (the least serious)
  2. debug
  3. info
  4. warn
  5. error
  6. fatal (the most serious)

The mapping of these log levels to the concepts used by the underlying logging system is implementation dependent. The implementation should ensure, though, that this ordering behaves as expected.

Performance is often a logging concern. By examining the appropriate property, a component can avoid expensive operations (producing information to be logged).

For example, if (log.isDebugEnabled()) { ... do something expensive ... log.debug(theResult); }

Configuration of the underlying logging system will generally be done external to the Logging APIs, through whatever mechanism is supported by that system.

  • Method Summary

    Modifier and Type
    Method
    Description
    void
    debug(Object message)
    Log a message with debug log level.
    void
    debug(Object message, Throwable t)
    Log a message and its cause with debug log level.
    void
    error(Object message)
    Log a message with error log level.
    void
    error(Object message, Throwable t)
    Log a message and its cause with error log level.
    void
    fatal(Object message)
    Log a message with fatal log level.
    void
    fatal(Object message, Throwable t)
    Log a message and its cause with fatal log level.
    void
    info(Object message)
    Log a message with info log level.
    void
    info(Object message, Throwable t)
    Log a message and its cause with info log level.
    boolean
    isDebugEnabled()
    Is debug logging currently enabled?
    boolean
    isErrorEnabled()
    Is error logging currently enabled?
    boolean
    isFatalEnabled()
    Is fatal logging currently enabled?
    boolean
    isInfoEnabled()
    Is info logging currently enabled?
    boolean
    isTraceEnabled()
    Is trace logging currently enabled?
    boolean
    isWarnEnabled()
    Is warn logging currently enabled?
    void
    trace(Object message)
    Log a message with trace log level.
    void
    trace(Object message, Throwable t)
    Log a message and its cause with trace log level.
    void
    warn(Object message)
    Log a message with warn log level.
    void
    warn(Object message, Throwable t)
    Log a message and its cause with warn log level.

  • Method Details

    • isDebugEnabled

      boolean isDebugEnabled()

      Is debug logging currently enabled?

      Call this method to prevent having to perform expensive operations (for example, String concatenation) when the log level is more than debug.

      Returns:
      true if debug level logging is enabled, otherwise false

    • isErrorEnabled

      boolean isErrorEnabled()

      Is error logging currently enabled?

      Call this method to prevent having to perform expensive operations (for example, String concatenation) when the log level is more than error.

      Returns:
      true if error level logging is enabled, otherwise false

    • isFatalEnabled

      boolean isFatalEnabled()

      Is fatal logging currently enabled?

      Call this method to prevent having to perform expensive operations (for example, String concatenation) when the log level is more than fatal.

      Returns:
      true if fatal level logging is enabled, otherwise false

    • isInfoEnabled

      boolean isInfoEnabled()

      Is info logging currently enabled?

      Call this method to prevent having to perform expensive operations (for example, String concatenation) when the log level is more than info.

      Returns:
      true if info level logging is enabled, otherwise false

    • isTraceEnabled

      boolean isTraceEnabled()

      Is trace logging currently enabled?

      Call this method to prevent having to perform expensive operations (for example, String concatenation) when the log level is more than trace.

      Returns:
      true if trace level logging is enabled, otherwise false

    • isWarnEnabled

      boolean isWarnEnabled()

      Is warn logging currently enabled?

      Call this method to prevent having to perform expensive operations (for example, String concatenation) when the log level is more than warn.

      Returns:
      true if warn level logging is enabled, otherwise false

    • trace

      void trace(Object message)

      Log a message with trace log level.

      Parameters:
      message - log this message

    • trace

      void trace(Object message, Throwable t)

      Log a message and its cause with trace log level.

      Parameters:
      message - log this message
      t - log this cause

    • debug

      void debug(Object message)

      Log a message with debug log level.

      Parameters:
      message - log this message

    • debug

      void debug(Object message, Throwable t)

      Log a message and its cause with debug log level.

      Parameters:
      message - log this message
      t - log this cause

    • info

      void info(Object message)

      Log a message with info log level.

      Parameters:
      message - log this message

    • info

      void info(Object message, Throwable t)

      Log a message and its cause with info log level.

      Parameters:
      message - log this message
      t - log this cause

    • warn

      void warn(Object message)

      Log a message with warn log level.

      Parameters:
      message - log this message

    • warn

      void warn(Object message, Throwable t)

      Log a message and its cause with warn log level.

      Parameters:
      message - log this message
      t - log this cause

    • error

      void error(Object message)

      Log a message with error log level.

      Parameters:
      message - log this message

    • error

      void error(Object message, Throwable t)

      Log a message and its cause with error log level.

      Parameters:
      message - log this message
      t - log this cause

    • fatal

      void fatal(Object message)

      Log a message with fatal log level.

      Parameters:
      message - log this message

    • fatal

      void fatal(Object message, Throwable t)

      Log a message and its cause with fatal log level.

      Parameters:
      message - log this message
      t - log this cause