Logger

All Known Subinterfaces:

LocationAwareLogger

All Known Implementing Classes:

EventRecodingLogger, MarkerIgnoringBase, NOPLogger, SimpleLogger, SubstituteLogger
```
public interface Logger
```
The org.slf4j.Logger interface is the main user entry point of SLF4J API. It is expected that logging takes place through concrete implementations of this interface.

Typical usage pattern:
```
 import org.slf4j.Logger;
 import org.slf4j.LoggerFactory;

 public class Wombat {

   final static Logger logger = LoggerFactory.getLogger(Wombat.class);
   Integer t;
   Integer oldT;

   public void setTemperature(Integer temperature) {
     oldT = t;
     t = temperature;
     logger.debug("Temperature set to {}. Old temperature was {}.", t, oldT);
     if(temperature.intValue() > 50) {
       logger.info("Temperature has risen above 50 degrees.");
     }
   }
 }
 
```
Be sure to read the FAQ entry relating to parameterized logging. Note that logging statements can be parameterized in presence of an exception/throwable.
Once you are comfortable using loggers, i.e. instances of this interface, consider using MDC as well as Markers.
Author:

Ceki Gülcü

Field Summary

Fields
Modifier and Type Field and Description

static String ROOT_LOGGER_NAME
Case insensitive String constant used to retrieve the name of the root logger.

Fields
Modifier and Type	Field and Description
`static String`	`ROOT_LOGGER_NAME` Case insensitive String constant used to retrieve the name of the root logger.

Method Summary

All Methods Instance Methods Abstract Methods
Modifier and Type	Method and Description
`void`	`debug(Marker marker, String msg)` Log a message with the specific Marker at the DEBUG level.
`void`	`debug(Marker marker, String format, Object... arguments)` This method is similar to `debug(String, Object...)` method except that the marker data is also taken into consideration.
`void`	`debug(Marker marker, String format, Object arg)` This method is similar to `debug(String, Object)` method except that the marker data is also taken into consideration.
`void`	`debug(Marker marker, String format, Object arg1, Object arg2)` This method is similar to `debug(String, Object, Object)` method except that the marker data is also taken into consideration.
`void`	`debug(Marker marker, String msg, Throwable t)` This method is similar to `debug(String, Throwable)` method except that the marker data is also taken into consideration.
`void`	`debug(String msg)` Log a message at the DEBUG level.
`void`	`debug(String format, Object... arguments)` Log a message at the DEBUG level according to the specified format and arguments.
`void`	`debug(String format, Object arg)` Log a message at the DEBUG level according to the specified format and argument.
`void`	`debug(String format, Object arg1, Object arg2)` Log a message at the DEBUG level according to the specified format and arguments.
`void`	`debug(String msg, Throwable t)` Log an exception (throwable) at the DEBUG level with an accompanying message.
`void`	`error(Marker marker, String msg)` Log a message with the specific Marker at the ERROR level.
`void`	`error(Marker marker, String format, Object... arguments)` This method is similar to `error(String, Object...)` method except that the marker data is also taken into consideration.
`void`	`error(Marker marker, String format, Object arg)` This method is similar to `error(String, Object)` method except that the marker data is also taken into consideration.
`void`	`error(Marker marker, String format, Object arg1, Object arg2)` This method is similar to `error(String, Object, Object)` method except that the marker data is also taken into consideration.
`void`	`error(Marker marker, String msg, Throwable t)` This method is similar to `error(String, Throwable)` method except that the marker data is also taken into consideration.
`void`	`error(String msg)` Log a message at the ERROR level.
`void`	`error(String format, Object... arguments)` Log a message at the ERROR level according to the specified format and arguments.
`void`	`error(String format, Object arg)` Log a message at the ERROR level according to the specified format and argument.
`void`	`error(String format, Object arg1, Object arg2)` Log a message at the ERROR level according to the specified format and arguments.
`void`	`error(String msg, Throwable t)` Log an exception (throwable) at the ERROR level with an accompanying message.
`String`	`getName()` Return the name of this `Logger` instance.
`void`	`info(Marker marker, String msg)` Log a message with the specific Marker at the INFO level.
`void`	`info(Marker marker, String format, Object... arguments)` This method is similar to `info(String, Object...)` method except that the marker data is also taken into consideration.
`void`	`info(Marker marker, String format, Object arg)` This method is similar to `info(String, Object)` method except that the marker data is also taken into consideration.
`void`	`info(Marker marker, String format, Object arg1, Object arg2)` This method is similar to `info(String, Object, Object)` method except that the marker data is also taken into consideration.
`void`	`info(Marker marker, String msg, Throwable t)` This method is similar to `info(String, Throwable)` method except that the marker data is also taken into consideration.
`void`	`info(String msg)` Log a message at the INFO level.
`void`	`info(String format, Object... arguments)` Log a message at the INFO level according to the specified format and arguments.
`void`	`info(String format, Object arg)` Log a message at the INFO level according to the specified format and argument.
`void`	`info(String format, Object arg1, Object arg2)` Log a message at the INFO level according to the specified format and arguments.
`void`	`info(String msg, Throwable t)` Log an exception (throwable) at the INFO level with an accompanying message.
`boolean`	`isDebugEnabled()` Is the logger instance enabled for the DEBUG level?
`boolean`	`isDebugEnabled(Marker marker)` Similar to `isDebugEnabled()` method except that the marker data is also taken into account.
`boolean`	`isErrorEnabled()` Is the logger instance enabled for the ERROR level?
`boolean`	`isErrorEnabled(Marker marker)` Similar to `isErrorEnabled()` method except that the marker data is also taken into consideration.
`boolean`	`isInfoEnabled()` Is the logger instance enabled for the INFO level?
`boolean`	`isInfoEnabled(Marker marker)` Similar to `isInfoEnabled()` method except that the marker data is also taken into consideration.
`boolean`	`isTraceEnabled()` Is the logger instance enabled for the TRACE level?
`boolean`	`isTraceEnabled(Marker marker)` Similar to `isTraceEnabled()` method except that the marker data is also taken into account.
`boolean`	`isWarnEnabled()` Is the logger instance enabled for the WARN level?
`boolean`	`isWarnEnabled(Marker marker)` Similar to `isWarnEnabled()` method except that the marker data is also taken into consideration.
`void`	`trace(Marker marker, String msg)` Log a message with the specific Marker at the TRACE level.
`void`	`trace(Marker marker, String format, Object... argArray)` This method is similar to `trace(String, Object...)` method except that the marker data is also taken into consideration.
`void`	`trace(Marker marker, String format, Object arg)` This method is similar to `trace(String, Object)` method except that the marker data is also taken into consideration.
`void`	`trace(Marker marker, String format, Object arg1, Object arg2)` This method is similar to `trace(String, Object, Object)` method except that the marker data is also taken into consideration.
`void`	`trace(Marker marker, String msg, Throwable t)` This method is similar to `trace(String, Throwable)` method except that the marker data is also taken into consideration.
`void`	`trace(String msg)` Log a message at the TRACE level.
`void`	`trace(String format, Object... arguments)` Log a message at the TRACE level according to the specified format and arguments.
`void`	`trace(String format, Object arg)` Log a message at the TRACE level according to the specified format and argument.
`void`	`trace(String format, Object arg1, Object arg2)` Log a message at the TRACE level according to the specified format and arguments.
`void`	`trace(String msg, Throwable t)` Log an exception (throwable) at the TRACE level with an accompanying message.
`void`	`warn(Marker marker, String msg)` Log a message with the specific Marker at the WARN level.
`void`	`warn(Marker marker, String format, Object... arguments)` This method is similar to `warn(String, Object...)` method except that the marker data is also taken into consideration.
`void`	`warn(Marker marker, String format, Object arg)` This method is similar to `warn(String, Object)` method except that the marker data is also taken into consideration.
`void`	`warn(Marker marker, String format, Object arg1, Object arg2)` This method is similar to `warn(String, Object, Object)` method except that the marker data is also taken into consideration.
`void`	`warn(Marker marker, String msg, Throwable t)` This method is similar to `warn(String, Throwable)` method except that the marker data is also taken into consideration.
`void`	`warn(String msg)` Log a message at the WARN level.
`void`	`warn(String format, Object... arguments)` Log a message at the WARN level according to the specified format and arguments.
`void`	`warn(String format, Object arg)` Log a message at the WARN level according to the specified format and argument.
`void`	`warn(String format, Object arg1, Object arg2)` Log a message at the WARN level according to the specified format and arguments.
`void`	`warn(String msg, Throwable t)` Log an exception (throwable) at the WARN level with an accompanying message.

- Field Detail
  - ROOT_LOGGER_NAME
```
static final String ROOT_LOGGER_NAME
```
    Case insensitive String constant used to retrieve the name of the root logger.
    
    Since:
    
    1.3
    
    See Also:
    
    Constant Field Values
- Method Detail
  - debug
```
void debug(Marker marker,
           String msg)
```
    Log a message with the specific Marker at the DEBUG level.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    msg - the message string to be logged
  - debug
```
void debug(Marker marker,
           String format,
           Object... arguments)
```
    This method is similar to debug(String, Object...) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arguments - a list of 3 or more arguments
  - debug
```
void debug(Marker marker,
           String format,
           Object arg)
```
    This method is similar to debug(String, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg - the argument
  - debug
```
void debug(Marker marker,
           String format,
           Object arg1,
           Object arg2)
```
    This method is similar to debug(String, Object, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
  - debug
```
void debug(Marker marker,
           String msg,
           Throwable t)
```
    This method is similar to debug(String, Throwable) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
  - debug
```
void debug(String msg)
```
    Log a message at the DEBUG level.
    
    Parameters:
    
    msg - the message string to be logged
  - debug
```
void debug(String format,
           Object... arguments)
```
    Log a message at the DEBUG level according to the specified format and arguments.
    
    This form avoids superfluous string concatenation when the logger is disabled for the DEBUG level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for DEBUG. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
    
    Parameters:
    
    format - the format string
    
    arguments - a list of 3 or more arguments
  - debug
```
void debug(String format,
           Object arg)
```
    Log a message at the DEBUG level according to the specified format and argument.
    
    This form avoids superfluous object creation when the logger is disabled for the DEBUG level.
    
    Parameters:
    
    format - the format string
    
    arg - the argument
  - debug
```
void debug(String format,
           Object arg1,
           Object arg2)
```
    Log a message at the DEBUG level according to the specified format and arguments.
    
    This form avoids superfluous object creation when the logger is disabled for the DEBUG level.
    
    Parameters:
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
  - debug
```
void debug(String msg,
           Throwable t)
```
    Log an exception (throwable) at the DEBUG level with an accompanying message.
    
    Parameters:
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
  - error
```
void error(Marker marker,
           String msg)
```
    Log a message with the specific Marker at the ERROR level.
    
    Parameters:
    
    marker - The marker specific to this log statement
    
    msg - the message string to be logged
  - error
```
void error(Marker marker,
           String format,
           Object... arguments)
```
    This method is similar to error(String, Object...) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arguments - a list of 3 or more arguments
  - error
```
void error(Marker marker,
           String format,
           Object arg)
```
    This method is similar to error(String, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg - the argument
  - error
```
void error(Marker marker,
           String format,
           Object arg1,
           Object arg2)
```
    This method is similar to error(String, Object, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
  - error
```
void error(Marker marker,
           String msg,
           Throwable t)
```
    This method is similar to error(String, Throwable) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
  - error
```
void error(String msg)
```
    Log a message at the ERROR level.
    
    Parameters:
    
    msg - the message string to be logged
  - error
```
void error(String format,
           Object... arguments)
```
    Log a message at the ERROR level according to the specified format and arguments.
    
    This form avoids superfluous string concatenation when the logger is disabled for the ERROR level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for ERROR. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
    
    Parameters:
    
    format - the format string
    
    arguments - a list of 3 or more arguments
  - error
```
void error(String format,
           Object arg)
```
    Log a message at the ERROR level according to the specified format and argument.
    
    This form avoids superfluous object creation when the logger is disabled for the ERROR level.
    
    Parameters:
    
    format - the format string
    
    arg - the argument
  - error
```
void error(String format,
           Object arg1,
           Object arg2)
```
    Log a message at the ERROR level according to the specified format and arguments.
    
    This form avoids superfluous object creation when the logger is disabled for the ERROR level.
    
    Parameters:
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
  - error
```
void error(String msg,
           Throwable t)
```
    Log an exception (throwable) at the ERROR level with an accompanying message.
    
    Parameters:
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
  - getName
```
String getName()
```
    Return the name of this Logger instance.
    
    Returns:
    
    name of this logger instance
  - info
```
void info(Marker marker,
          String msg)
```
    Log a message with the specific Marker at the INFO level.
    
    Parameters:
    
    marker - The marker specific to this log statement
    
    msg - the message string to be logged
  - info
```
void info(Marker marker,
          String format,
          Object... arguments)
```
    This method is similar to info(String, Object...) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arguments - a list of 3 or more arguments
  - info
```
void info(Marker marker,
          String format,
          Object arg)
```
    This method is similar to info(String, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg - the argument
  - info
```
void info(Marker marker,
          String format,
          Object arg1,
          Object arg2)
```
    This method is similar to info(String, Object, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
  - info
```
void info(Marker marker,
          String msg,
          Throwable t)
```
    This method is similar to info(String, Throwable) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data for this log statement
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
  - info
```
void info(String msg)
```
    Log a message at the INFO level.
    
    Parameters:
    
    msg - the message string to be logged
  - info
```
void info(String format,
          Object... arguments)
```
    Log a message at the INFO level according to the specified format and arguments.
    
    This form avoids superfluous string concatenation when the logger is disabled for the INFO level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for INFO. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
    
    Parameters:
    
    format - the format string
    
    arguments - a list of 3 or more arguments
  - info
```
void info(String format,
          Object arg)
```
    Log a message at the INFO level according to the specified format and argument.
    
    This form avoids superfluous object creation when the logger is disabled for the INFO level.
    
    Parameters:
    
    format - the format string
    
    arg - the argument
  - info
```
void info(String format,
          Object arg1,
          Object arg2)
```
    Log a message at the INFO level according to the specified format and arguments.
    
    This form avoids superfluous object creation when the logger is disabled for the INFO level.
    
    Parameters:
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
  - info
```
void info(String msg,
          Throwable t)
```
    Log an exception (throwable) at the INFO level with an accompanying message.
    
    Parameters:
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
  - isDebugEnabled
```
boolean isDebugEnabled()
```
    Is the logger instance enabled for the DEBUG level?
    
    Returns:
    
    True if this Logger is enabled for the DEBUG level, false otherwise.
  - isDebugEnabled
```
boolean isDebugEnabled(Marker marker)
```
    Similar to isDebugEnabled() method except that the marker data is also taken into account.
    
    Parameters:
    
    marker - The marker data to take into consideration
    
    Returns:
    
    True if this Logger is enabled for the DEBUG level, false otherwise.
  - isErrorEnabled
```
boolean isErrorEnabled()
```
    Is the logger instance enabled for the ERROR level?
    
    Returns:
    
    True if this Logger is enabled for the ERROR level, false otherwise.
  - isErrorEnabled
```
boolean isErrorEnabled(Marker marker)
```
    Similar to isErrorEnabled() method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - The marker data to take into consideration
    
    Returns:
    
    True if this Logger is enabled for the ERROR level, false otherwise.
  - isInfoEnabled
```
boolean isInfoEnabled()
```
    Is the logger instance enabled for the INFO level?
    
    Returns:
    
    True if this Logger is enabled for the INFO level, false otherwise.
  - isInfoEnabled
```
boolean isInfoEnabled(Marker marker)
```
    Similar to isInfoEnabled() method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - The marker data to take into consideration
    
    Returns:
    
    true if this logger is warn enabled, false otherwise
  - isTraceEnabled
```
boolean isTraceEnabled()
```
    Is the logger instance enabled for the TRACE level?
    
    Returns:
    
    True if this Logger is enabled for the TRACE level, false otherwise.
    
    Since:
    
    1.4
  - isTraceEnabled
```
boolean isTraceEnabled(Marker marker)
```
    Similar to isTraceEnabled() method except that the marker data is also taken into account.
    
    Parameters:
    
    marker - The marker data to take into consideration
    
    Returns:
    
    True if this Logger is enabled for the TRACE level, false otherwise.
    
    Since:
    
    1.4
  - isWarnEnabled
```
boolean isWarnEnabled()
```
    Is the logger instance enabled for the WARN level?
    
    Returns:
    
    True if this Logger is enabled for the WARN level, false otherwise.
  - isWarnEnabled
```
boolean isWarnEnabled(Marker marker)
```
    Similar to isWarnEnabled() method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - The marker data to take into consideration
    
    Returns:
    
    True if this Logger is enabled for the WARN level, false otherwise.
  - trace
```
void trace(Marker marker,
           String msg)
```
    Log a message with the specific Marker at the TRACE level.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    msg - the message string to be logged
    
    Since:
    
    1.4
  - trace
```
void trace(Marker marker,
           String format,
           Object... argArray)
```
    This method is similar to trace(String, Object...) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    argArray - an array of arguments
    
    Since:
    
    1.4
  - trace
```
void trace(Marker marker,
           String format,
           Object arg)
```
    This method is similar to trace(String, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg - the argument
    
    Since:
    
    1.4
  - trace
```
void trace(Marker marker,
           String format,
           Object arg1,
           Object arg2)
```
    This method is similar to trace(String, Object, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
    
    Since:
    
    1.4
  - trace
```
void trace(Marker marker,
           String msg,
           Throwable t)
```
    This method is similar to trace(String, Throwable) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
    
    Since:
    
    1.4
  - trace
```
void trace(String msg)
```
    Log a message at the TRACE level.
    
    Parameters:
    
    msg - the message string to be logged
    
    Since:
    
    1.4
  - trace
```
void trace(String format,
           Object... arguments)
```
    Log a message at the TRACE level according to the specified format and arguments.
    
    This form avoids superfluous string concatenation when the logger is disabled for the TRACE level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for TRACE. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
    
    Parameters:
    
    format - the format string
    
    arguments - a list of 3 or more arguments
    
    Since:
    
    1.4
  - trace
```
void trace(String format,
           Object arg)
```
    Log a message at the TRACE level according to the specified format and argument.
    
    This form avoids superfluous object creation when the logger is disabled for the TRACE level.
    
    Parameters:
    
    format - the format string
    
    arg - the argument
    
    Since:
    
    1.4
  - trace
```
void trace(String format,
           Object arg1,
           Object arg2)
```
    Log a message at the TRACE level according to the specified format and arguments.
    
    This form avoids superfluous object creation when the logger is disabled for the TRACE level.
    
    Parameters:
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
    
    Since:
    
    1.4
  - trace
```
void trace(String msg,
           Throwable t)
```
    Log an exception (throwable) at the TRACE level with an accompanying message.
    
    Parameters:
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
    
    Since:
    
    1.4
  - warn
```
void warn(Marker marker,
          String msg)
```
    Log a message with the specific Marker at the WARN level.
    
    Parameters:
    
    marker - The marker specific to this log statement
    
    msg - the message string to be logged
  - warn
```
void warn(Marker marker,
          String format,
          Object... arguments)
```
    This method is similar to warn(String, Object...) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arguments - a list of 3 or more arguments
  - warn
```
void warn(Marker marker,
          String format,
          Object arg)
```
    This method is similar to warn(String, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg - the argument
  - warn
```
void warn(Marker marker,
          String format,
          Object arg1,
          Object arg2)
```
    This method is similar to warn(String, Object, Object) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data specific to this log statement
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
  - warn
```
void warn(Marker marker,
          String msg,
          Throwable t)
```
    This method is similar to warn(String, Throwable) method except that the marker data is also taken into consideration.
    
    Parameters:
    
    marker - the marker data for this log statement
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log
  - warn
```
void warn(String msg)
```
    Log a message at the WARN level.
    
    Parameters:
    
    msg - the message string to be logged
  - warn
```
void warn(String format,
          Object... arguments)
```
    Log a message at the WARN level according to the specified format and arguments.
    
    This form avoids superfluous string concatenation when the logger is disabled for the WARN level. However, this variant incurs the hidden (and relatively small) cost of creating an Object[] before invoking the method, even if this logger is disabled for WARN. The variants taking one and two arguments exist solely in order to avoid this hidden cost.
    
    Parameters:
    
    format - the format string
    
    arguments - a list of 3 or more arguments
  - warn
```
void warn(String format,
          Object arg)
```
    Log a message at the WARN level according to the specified format and argument.
    
    This form avoids superfluous object creation when the logger is disabled for the WARN level.
    
    Parameters:
    
    format - the format string
    
    arg - the argument
  - warn
```
void warn(String format,
          Object arg1,
          Object arg2)
```
    Log a message at the WARN level according to the specified format and arguments.
    
    This form avoids superfluous object creation when the logger is disabled for the WARN level.
    
    Parameters:
    
    format - the format string
    
    arg1 - the first argument
    
    arg2 - the second argument
  - warn
```
void warn(String msg,
          Throwable t)
```
    Log an exception (throwable) at the WARN level with an accompanying message.
    
    Parameters:
    
    msg - the message accompanying the exception
    
    t - the exception (throwable) to log

Interface Logger

Typical usage pattern:

Field Summary

Method Summary

Field Detail

ROOT_LOGGER_NAME

Method Detail

debug

debug

debug

debug

debug

debug

debug

debug

debug

debug

error

error

error

error

error

error

error

error

error

error

getName

info

info

info

info

info

info

info

info

info

info

isDebugEnabled

isDebugEnabled

isErrorEnabled

isErrorEnabled

isInfoEnabled

isInfoEnabled

isTraceEnabled

isTraceEnabled

isWarnEnabled

isWarnEnabled

trace

trace

trace

trace

trace

trace

trace

trace

trace

trace

warn

warn

warn

warn

warn

warn

warn

warn

warn

warn