Top Description Methods
org.apache.commons.logging

public Interface Log

Known Direct Implementers
org.apache.commons.logging.LogAdapter.Log4jLog, org.apache.commons.logging.LogAdapter.Slf4jLog, org.apache.commons.logging.LogAdapter.JavaUtilLog, org.apache.commons.logging.impl.NoOpLog
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.

Author
Juergen Hoeller (for the spring-jcl variant)
Since
5.0

Method Summary

Modifier and TypeMethod and Description
public void
debug(Object
log this message
message)

Logs a message with debug log level.

public void
debug(Object
log this message
message, Throwable
log this cause
t)

Logs an error with debug log level.

public void
error(Object
log this message
message)

Logs a message with error log level.

public void
error(Object
log this message
message, Throwable
log this cause
t)

Logs an error with error log level.

public void
fatal(Object
log this message
message)

Logs a message with fatal log level.

public void
fatal(Object
log this message
message, Throwable
log this cause
t)

Logs an error with fatal log level.

public void
info(Object
log this message
message)

Logs a message with info log level.

public void
info(Object
log this message
message, Throwable
log this cause
t)

Logs an error with info log level.

public boolean

Returns:

true if debug is enabled in the underlying logger.
isDebugEnabled()

Is debug logging currently enabled?

public boolean

Returns:

true if error is enabled in the underlying logger.
isErrorEnabled()

Is error logging currently enabled?

public boolean

Returns:

true if fatal is enabled in the underlying logger.
isFatalEnabled()

Is fatal logging currently enabled?

public boolean

Returns:

true if info is enabled in the underlying logger.
isInfoEnabled()

Is info logging currently enabled?

public boolean

Returns:

true if trace is enabled in the underlying logger.
isTraceEnabled()

Is trace logging currently enabled?

public boolean

Returns:

true if warn is enabled in the underlying logger.
isWarnEnabled()

Is warn logging currently enabled?

public void
trace(Object
log this message
message)

Logs a message with trace log level.

public void
trace(Object
log this message
message, Throwable
log this cause
t)

Logs an error with trace log level.

public void
warn(Object
log this message
message)

Logs a message with warn log level.

public void
warn(Object
log this message
message, Throwable
log this cause
t)

Logs an error with warn log level.

Method Detail

debugback to summary
public void debug(Object message)

Logs a message with debug log level.

Parameters
message:Object

log this message

debugback to summary
public void debug(Object message, Throwable t)

Logs an error with debug log level.

Parameters
message:Object

log this message

t:Throwable

log this cause

errorback to summary
public void error(Object message)

Logs a message with error log level.

Parameters
message:Object

log this message

errorback to summary
public void error(Object message, Throwable t)

Logs an error with error log level.

Parameters
message:Object

log this message

t:Throwable

log this cause

fatalback to summary
public void fatal(Object message)

Logs a message with fatal log level.

Parameters
message:Object

log this message

fatalback to summary
public void fatal(Object message, Throwable t)

Logs an error with fatal log level.

Parameters
message:Object

log this message

t:Throwable

log this cause

infoback to summary
public void info(Object message)

Logs a message with info log level.

Parameters
message:Object

log this message

infoback to summary
public void info(Object message, Throwable t)

Logs an error with info log level.

Parameters
message:Object

log this message

t:Throwable

log this cause

isDebugEnabledback to summary
public 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:boolean

true if debug is enabled in the underlying logger.

isErrorEnabledback to summary
public 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:boolean

true if error is enabled in the underlying logger.

isFatalEnabledback to summary
public 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:boolean

true if fatal is enabled in the underlying logger.

isInfoEnabledback to summary
public 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:boolean

true if info is enabled in the underlying logger.

isTraceEnabledback to summary
public 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:boolean

true if trace is enabled in the underlying logger.

isWarnEnabledback to summary
public 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:boolean

true if warn is enabled in the underlying logger.

traceback to summary
public void trace(Object message)

Logs a message with trace log level.

Parameters
message:Object

log this message

traceback to summary
public void trace(Object message, Throwable t)

Logs an error with trace log level.

Parameters
message:Object

log this message

t:Throwable

log this cause

warnback to summary
public void warn(Object message)

Logs a message with warn log level.

Parameters
message:Object

log this message

warnback to summary
public void warn(Object message, Throwable t)

Logs an error with warn log level.

Parameters
message:Object

log this message

t:Throwable

log this cause