com.launchdarkly.logging

Class LDLogger

java.lang.Object

com.launchdarkly.logging.LDLogger

public final class LDLogger
extends java.lang.Object

A basic logger facade that delegates to an underlying output implementation.

The LaunchDarkly SDK sends all of its logging output through this class. What happens to the output depends on the LDLogAdapter that has been used to configure the SDK.

Applications will not normally need to interact with LDLogger directly. See the SDK's configuration builder for how to configure logging using a log adapter.

The logger has output methods for each of the levels defined in LDLogLevel. For efficiency (to avoid unnecessarily creating varargs arrays), each level has four methods: one for non-parameterized messages, one for messages with a single parameter, one for messages with two parameters, and one for messages with an arbitrary number of parameters.

Parameter substitution uses the syntax defined by SimpleFormat: the format string can contain "{}" placeholders, which are replaced by the result of calling toString() on the corresponding parameter.

To avoid unnecessary computations, toString() is not called on parameters (or, in the single-argument methods, on the single Object) if logging at the specified level is disabled.

Method Summary

Modifier and Type	Method and Description
void	debug(java.lang.Object message) Writes a message at LDLogLevel.DEBUG level.
void	debug(java.lang.String format, java.lang.Object... params) Writes a message at LDLogLevel.DEBUG level with any number of parameters.
void	debug(java.lang.String format, java.lang.Object param) Writes a message at LDLogLevel.DEBUG level with one parameter.
void	debug(java.lang.String format, java.lang.Object param1, java.lang.Object param2) Writes a message at LDLogLevel.DEBUG level with two parameters.
void	error(java.lang.Object message) Writes a message at LDLogLevel.ERROR level.
void	error(java.lang.String format, java.lang.Object... params) Writes a message at LDLogLevel.ERROR level with any number of parameters.
void	error(java.lang.String format, java.lang.Object param) Writes a message at LDLogLevel.ERROR level with one parameter.
void	error(java.lang.String format, java.lang.Object param1, java.lang.Object param2) Writes a message at LDLogLevel.ERROR level with two parameters.
void	info(java.lang.Object message) Writes a message at LDLogLevel.INFO level.
void	info(java.lang.String format, java.lang.Object... params) Writes a message at LDLogLevel.INFO level with any number of parameters.
void	info(java.lang.String format, java.lang.Object param) Writes a message at LDLogLevel.INFO level with one parameter.
void	info(java.lang.String format, java.lang.Object param1, java.lang.Object param2) Writes a message at LDLogLevel.INFO level with two parameters.
boolean	isEnabled(LDLogLevel level) Tests whether log output for a certain level is at least potentially visible.
static LDLogger	none() Returns a logger instance that does nothing.
LDLogger	subLogger(java.lang.String nameSuffix) Returns a logger instance derived from this instance.
void	warn(java.lang.Object message) Writes a message at LDLogLevel.WARN level.
void	warn(java.lang.String format, java.lang.Object... params) Writes a message at LDLogLevel.WARN level with any number of parameters.
void	warn(java.lang.String format, java.lang.Object param) Writes a message at LDLogLevel.WARN level with one parameters.
void	warn(java.lang.String format, java.lang.Object param1, java.lang.Object param2) Writes a message at LDLogLevel.WARN level with two parameters.
static LDLogger	withAdapter(LDLogAdapter adapter, java.lang.String name) Returns a logger instance using the specified adapter.

Methods inherited from class java.lang.Object

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

Method Detail

withAdapter

public static LDLogger withAdapter(LDLogAdapter adapter,
                                   java.lang.String name)

Returns a logger instance using the specified adapter.

Parameters:

adapter - the LDLogAdapter that provides the output implementation

name - an identifier for the logger which may be included in output

Returns:

a logger instance

none

public static LDLogger none()

Returns a logger instance that does nothing.

Returns:

a no-op logger

subLogger

public LDLogger subLogger(java.lang.String nameSuffix)

Returns a logger instance derived from this instance.

Parameters:

nameSuffix - will be appended to the current logger's name, separated by a period, to create the new logger's name

Returns:

a logger instance that uses the same adapter

isEnabled

public boolean isEnabled(LDLogLevel level)

Tests whether log output for a certain level is at least potentially visible.

Generally, any desired level filtering should be set up in the initial logging configuration, and code that generates log messages should simply call methods like info(Object) without having to know whether that particular level is enabled or is being filtered out. However, if some kind of log message is particularly expensive to compute, you may call isEnabled(LDLogLevel); a false value means you can skip trying to log any message at that level.

Another approach is to generate any computationally expensive output lazily, such as by using the methods in LogValues.

Parameters:

level - a log level

Returns:

true if this level is potentially visible

debug

public void debug(java.lang.Object message)

Writes a message at LDLogLevel.DEBUG level.

Parameters:

message - the message (will be converted to a string with toString())

debug

public void debug(java.lang.String format,
                  java.lang.Object param)

Writes a message at LDLogLevel.DEBUG level with one parameter.

Parameters:

format - the format string, containing "{}" placeholders

param - the parameter

debug

public void debug(java.lang.String format,
                  java.lang.Object param1,
                  java.lang.Object param2)

Writes a message at LDLogLevel.DEBUG level with two parameters.

Parameters:

format - the format string, containing "{}" placeholders

param1 - the first parameter

param2 - the second parameter

debug

public void debug(java.lang.String format,
                  java.lang.Object... params)

Writes a message at LDLogLevel.DEBUG level with any number of parameters.

Parameters:

format - the format string, containing "{}" placeholders

params - the parameters

info

public void info(java.lang.Object message)

Writes a message at LDLogLevel.INFO level.

Parameters:

message - the message (will be converted to a string with toString())

info

public void info(java.lang.String format,
                 java.lang.Object param)

Writes a message at LDLogLevel.INFO level with one parameter.

Parameters:

format - the format string, containing "{}" placeholders

param - the parameter

info

public void info(java.lang.String format,
                 java.lang.Object param1,
                 java.lang.Object param2)

Writes a message at LDLogLevel.INFO level with two parameters.

Parameters:

format - the format string, containing "{}" placeholders

param1 - the first parameter

param2 - the second parameter

info

public void info(java.lang.String format,
                 java.lang.Object... params)

Writes a message at LDLogLevel.INFO level with any number of parameters.

Parameters:

format - the format string, containing "{}" placeholders

params - the parameters

warn

public void warn(java.lang.Object message)

Writes a message at LDLogLevel.WARN level.

Parameters:

message - the message (will be converted to a string with toString())

warn

public void warn(java.lang.String format,
                 java.lang.Object param)

Writes a message at LDLogLevel.WARN level with one parameters.

Parameters:

format - the format string, containing "{}" placeholders

param - the parameter

warn

public void warn(java.lang.String format,
                 java.lang.Object param1,
                 java.lang.Object param2)

Writes a message at LDLogLevel.WARN level with two parameters.

Parameters:

format - the format string, containing "{}" placeholders

param1 - the first parameter

param2 - the second parameter

warn

public void warn(java.lang.String format,
                 java.lang.Object... params)

Writes a message at LDLogLevel.WARN level with any number of parameters.

Parameters:

format - the format string, containing "{}" placeholders

params - the parameters

error

public void error(java.lang.Object message)

Writes a message at LDLogLevel.ERROR level.

Parameters:

message - the message (will be converted to a string with toString())

error

public void error(java.lang.String format,
                  java.lang.Object param)

Writes a message at LDLogLevel.ERROR level with one parameter.

Parameters:

format - the format string, containing "{}" placeholders

param - the parameter

error

public void error(java.lang.String format,
                  java.lang.Object param1,
                  java.lang.Object param2)

Writes a message at LDLogLevel.ERROR level with two parameters.

Parameters:

format - the format string, containing "{}" placeholders

param1 - the first parameter

param2 - the second parameter

error

public void error(java.lang.String format,
                  java.lang.Object... params)

Writes a message at LDLogLevel.ERROR level with any number of parameters.

Parameters:

format - the format string, containing "{}" placeholders

params - the parameters