jsimple.logging

Class Logger

java.lang.Object

jsimple.logging.Logger

Direct Known Subclasses:

NOPLogger, StdLogger

public abstract class Logger
extends java.lang.Object

The jsimple.logging.Logger interface is the main user entry point of JSimple logging API. It is expected that logging takes place through concrete implementations of this interface.

Typical usage pattern:

 import jsimple.logging.Logger;
 import jsimple.logging.LoggerFactory;

 public class Wombat {

   final static Logger logger = LoggerFactory.getLogger("Wombat");
   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.");
     }
   }
 }
 

This class was adapted from SLF4J, version 1.7.5. The main change from SLF4J was that Marker support was removed, as it's not (yet) supported in JSimple logging. Also, generic log methods were added, taking a Level parameter, like in JUL (java util logging) & these methods are used for default implementations.

Field Summary

Fields

Modifier and Type	Field and Description
java.lang.String	ROOT_LOGGER_NAME Case insensitive String constant used to retrieve the name of the root logger.

Constructor Summary

Constructors

Constructor and Description
Logger()

Method Summary

Modifier and Type	Method and Description
void	debug(java.lang.String msg) Log a message at the DEBUG level.
void	debug(java.lang.String format, java.lang.Object... arguments) Log a message at the DEBUG level according to the specified format and arguments.
void	debug(java.lang.String format, java.lang.Object arg) Log a message at the DEBUG level according to the specified format and argument.
void	debug(java.lang.String format, java.lang.Object arg1, java.lang.Object arg2) Log a message at the DEBUG level according to the specified format and arguments.
void	debug(java.lang.String msg, java.lang.Throwable t) Log an exception (throwable) at the DEBUG level with an accompanying message.
LogEnterLeave	debugEnterLeave(java.lang.String msg)
LogEnterLeave	debugEnterLeave(java.lang.String format, java.lang.Object... arguments)
void	error(java.lang.String msg) Log a message at the ERROR level.
void	error(java.lang.String format, java.lang.Object... arguments) Log a message at the ERROR level according to the specified format and arguments.
void	error(java.lang.String format, java.lang.Object arg) Log a message at the ERROR level according to the specified format and argument.
void	error(java.lang.String format, java.lang.Object arg1, java.lang.Object arg2) Log a message at the ERROR level according to the specified format and arguments.
void	error(java.lang.String msg, java.lang.Throwable t) Log an exception (throwable) at the ERROR level with an accompanying message.
abstract java.lang.String	getName() Return the name of this Logger instance.
void	info(java.lang.String msg) Log a message at the INFO level.
void	info(java.lang.String format, java.lang.Object... arguments) Log a message at the INFO level according to the specified format and arguments.
void	info(java.lang.String format, java.lang.Object arg) Log a message at the INFO level according to the specified format and argument.
void	info(java.lang.String format, java.lang.Object arg1, java.lang.Object arg2) Log a message at the INFO level according to the specified format and arguments.
void	info(java.lang.String msg, java.lang.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	isErrorEnabled() Is the logger instance enabled for the ERROR level?
boolean	isInfoEnabled() Is the logger instance enabled for the INFO level?
abstract boolean	isLevelEnabled(Level level) Is the logger instance enabled for the specified level?
boolean	isTraceEnabled() Is the logger instance enabled for the TRACE level?
boolean	isWarnEnabled() Is the logger instance enabled for the WARN level?
void	log(Level level, java.lang.String msg) Log a message at the specified level.
void	log(Level level, java.lang.String format, java.lang.Object... arguments) Log a message at the specified level according to the specified format and arguments.
void	log(Level level, java.lang.String format, java.lang.Object arg) Log a message at the specified level according to the specified format and argument.
void	log(Level level, java.lang.String format, java.lang.Object arg1, java.lang.Object arg2) Log a message at the specified level according to the specified format and arguments.
abstract void	log(Level level, java.lang.String msg, java.lang.Throwable t) Log an exception (throwable) at the specified level with an accompanying message.
LogEnterLeave	logEnterLeave(Level level, java.lang.String format, java.lang.Object... arguments)
abstract LogEnterLeave	logStartAndEndWithVarargs(Level level, java.lang.String format, java.lang.Object... arguments) Log start and end messages at the specified level, with the specified message format and arguments.
abstract void	logWithVarargs(Level level, java.lang.String format, java.lang.Object... arguments) Log a message at the specified level, with the specified message format and arguments.
abstract void	setLevel(Level level) Set the level for this logger.
void	trace(java.lang.String msg) Log a message at the TRACE level.
void	trace(java.lang.String format, java.lang.Object... arguments) Log a message at the TRACE level according to the specified format and arguments.
void	trace(java.lang.String format, java.lang.Object arg) Log a message at the TRACE level according to the specified format and argument.
void	trace(java.lang.String format, java.lang.Object arg1, java.lang.Object arg2) Log a message at the TRACE level according to the specified format and arguments.
void	trace(java.lang.String msg, java.lang.Throwable t) Log an exception (throwable) at the TRACE level with an accompanying message.
LogEnterLeave	traceEnterLeave(java.lang.String msg)
LogEnterLeave	traceEnterLeave(java.lang.String format, java.lang.Object... arguments)
void	warn(java.lang.String msg) Log a message at the WARN level.
void	warn(java.lang.String format, java.lang.Object... arguments) Log a message at the WARN level according to the specified format and arguments.
void	warn(java.lang.String format, java.lang.Object arg) Log a message at the WARN level according to the specified format and argument.
void	warn(java.lang.String format, java.lang.Object arg1, java.lang.Object arg2) Log a message at the WARN level according to the specified format and arguments.
void	warn(java.lang.String msg, java.lang.Throwable t) Log an exception (throwable) at the WARN level with an accompanying message.

Methods inherited from class java.lang.Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Field Detail

ROOT_LOGGER_NAME

public final java.lang.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

Constructor Detail

Logger

public Logger()

Method Detail

getName

public abstract java.lang.String getName()

Return the name of this Logger instance.

Returns:

name of this logger instance

isTraceEnabled

public 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

trace

public void trace(java.lang.String msg)

Log a message at the TRACE level.

Parameters:

msg - the message string to be logged

Since:

1.4

trace

public void trace(java.lang.String format,
                  java.lang.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

public void trace(java.lang.String format,
                  java.lang.Object arg1,
                  java.lang.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

public void trace(java.lang.String format,
                  java.lang.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

public void trace(java.lang.String msg,
                  java.lang.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

isDebugEnabled

public boolean isDebugEnabled()

Is the logger instance enabled for the DEBUG level?

Returns:

true if this Logger is enabled for the DEBUG level, false otherwise.

debug

public void debug(java.lang.String msg)

Log a message at the DEBUG level.

Parameters:

msg - the message string to be logged

debug

public void debug(java.lang.String format,
                  java.lang.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

public void debug(java.lang.String format,
                  java.lang.Object arg1,
                  java.lang.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

public void debug(java.lang.String format,
                  java.lang.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

public void debug(java.lang.String msg,
                  java.lang.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

isInfoEnabled

public boolean isInfoEnabled()

Is the logger instance enabled for the INFO level?

Returns:

true if this Logger is enabled for the INFO level, false otherwise.

info

public void info(java.lang.String msg)

Log a message at the INFO level.

Parameters:

msg - the message string to be logged

info

public void info(java.lang.String format,
                 java.lang.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

public void info(java.lang.String format,
                 java.lang.Object arg1,
                 java.lang.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

public void info(java.lang.String format,
                 java.lang.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

public void info(java.lang.String msg,
                 java.lang.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

isWarnEnabled

public boolean isWarnEnabled()

Is the logger instance enabled for the WARN level?

Returns:

true if this Logger is enabled for the WARN level, false otherwise.

warn

public void warn(java.lang.String msg)

Log a message at the WARN level.

Parameters:

msg - the message string to be logged

warn

public void warn(java.lang.String format,
                 java.lang.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

public void warn(java.lang.String format,
                 java.lang.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

public void warn(java.lang.String format,
                 java.lang.Object arg1,
                 java.lang.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

public void warn(java.lang.String msg,
                 java.lang.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

isErrorEnabled

public boolean isErrorEnabled()

Is the logger instance enabled for the ERROR level?

Returns:

true if this Logger is enabled for the ERROR level, false otherwise.

error

public void error(java.lang.String msg)

Log a message at the ERROR level.

Parameters:

msg - the message string to be logged

error

public void error(java.lang.String format,
                  java.lang.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

public void error(java.lang.String format,
                  java.lang.Object arg1,
                  java.lang.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

public void error(java.lang.String format,
                  java.lang.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

public void error(java.lang.String msg,
                  java.lang.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

isLevelEnabled

public abstract boolean isLevelEnabled(Level level)

Is the logger instance enabled for the specified level?

Returns:

true if this Logger is enabled for the specified level, false otherwise.

setLevel

public abstract void setLevel(Level level)

Set the level for this logger. The logger implementation is free to define the exact semantics of changing the level--what other loggers may be affected (if there's some kind of hierarchy), etc.

Parameters:

level - new level

log

public void log(Level level,
                java.lang.String msg)

Log a message at the specified level.

Parameters:

level - logging level to log at

msg - the message string to be logged

log

public void log(Level level,
                java.lang.String format,
                java.lang.Object arg)

Log a message at the specified level according to the specified format and argument.

This form avoids superfluous object creation when the logger is disabled for the level.

Parameters:

level - logging level to log at

format - the format string

arg - the argument

log

public void log(Level level,
                java.lang.String format,
                java.lang.Object arg1,
                java.lang.Object arg2)

Log a message at the specified level according to the specified format and arguments.

This form avoids superfluous object creation when the logger is disabled for the level.

Parameters:

level - logging level to log at

format - the format string

arg1 - the first argument

arg2 - the second argument

log

public void log(Level level,
                java.lang.String format,
                java.lang.Object... arguments)

Log a message at the specified level according to the specified format and arguments.

This form avoids superfluous string concatenation when the logger is disabled for the 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:

level - logging level to log at

format - the format string

arguments - a list of 3 or more arguments

logWithVarargs

public abstract void logWithVarargs(Level level,
                                    java.lang.String format,
                                    java.lang.Object... arguments)

Log a message at the specified level, with the specified message format and arguments. This method is the same as the log varargs method, except that it has a different name, with no overloads, to force use of the varargs version no matter how few arguments are passed.

Parameters:

level - logging level to log at

format - the format string

arguments - a list of 0 or more arguments

log

public abstract void log(Level level,
                         java.lang.String msg,
                         java.lang.Throwable t)

Log an exception (throwable) at the specified level with an accompanying message.

Parameters:

level - logging level to log at

msg - the message accompanying the exception

t - the exception (throwable) to log

debugEnterLeave

public LogEnterLeave debugEnterLeave(java.lang.String msg)

debugEnterLeave

public LogEnterLeave debugEnterLeave(java.lang.String format,
                                     java.lang.Object... arguments)

traceEnterLeave

public LogEnterLeave traceEnterLeave(java.lang.String msg)

traceEnterLeave

public LogEnterLeave traceEnterLeave(java.lang.String format,
                                     java.lang.Object... arguments)

logEnterLeave

public LogEnterLeave logEnterLeave(Level level,
                                   java.lang.String format,
                                   java.lang.Object... arguments)

logStartAndEndWithVarargs

public abstract LogEnterLeave logStartAndEndWithVarargs(Level level,
                                                        java.lang.String format,
                                                        java.lang.Object... arguments)

Log start and end messages at the specified level, with the specified message format and arguments. This method is the same as the logEnterLeave varargs method, except that it has a different name, with no overloads, to force use of the varargs version no matter how few arguments are passed.

Parameters:

level - logging level to log at

format - the format string

arguments - a list of 0 or more arguments