public abstract class Category extends Object
Logger subclass. It
will be kept around to preserve backward compatibility until mid
2003.
Logger is a subclass of Category, i.e. it extends
Category. In other words, a logger is a category. Thus,
all operations that can be performed on a category can be
performed on a logger. Internally, whenever log4j is asked to
produce a Category object, it will instead produce a Logger
object. Log4j 1.2 will never produce Category objects but
only Logger instances. In order to preserve backward
compatibility, methods that previously accepted category objects
still continue to accept category objects.
For example, the following are all legal and will work as expected.
// Deprecated form:
Category cat = Category.getInstance("foo.bar")
// Preferred form for retrieving loggers:
Logger logger = Logger.getLogger("foo.bar")
The first form is deprecated and should be avoided.
There is absolutely no need for new client code to use or
refer to the Category class. Whenever possible,
please avoid referring to it or using it.
See the short manual for an introduction on this class.
See the document entitled preparing for log4j 1.3 for a more detailed discussion.
| Modifier and Type | Field and Description |
|---|---|
protected PaxLogger |
m_delegate |
| Modifier and Type | Method and Description |
|---|---|
void |
assertLog(boolean assertion,
String msg)
|
void |
debug(Object message)
Log a message object with the DEBUG level.
|
void |
debug(Object message,
Throwable t)
Log a message object with the
DEBUG level including the
stack trace of the Throwablet passed as parameter. |
void |
error(Object message)
Log a message object with the ERROR Level.
|
void |
error(Object message,
Throwable t)
Log a message object with the
ERROR level including the
stack trace of the Throwablet passed as parameter. |
void |
fatal(Object message)
Log a message object with the FATAL Level.
|
void |
fatal(Object message,
Throwable t)
Log a message object with the
FATAL level including the
stack trace of the Throwablet passed as parameter. |
Level |
getEffectiveLevel()
Starting from this category, search the category hierarchy for a
non-null level and return it.
|
static Category |
getInstance(Class clazz)
Deprecated.
Please make sure to use
Logger.getLogger(Class) instead. |
static Category |
getInstance(String name)
Deprecated.
Make sure to use
Logger.getLogger(String) instead. |
String |
getName()
Return the category name.
|
void |
info(Object message)
Log a message object with the INFO Level.
|
void |
info(Object message,
Throwable t)
Log a message object with the
INFO level including the stack
trace of the Throwablet passed as parameter. |
boolean |
isDebugEnabled()
Check whether this category is enabled for the
DEBUG Level. |
boolean |
isEnabledFor(Priority priority)
Check whether this category is enabled for a given
Level passed as parameter. |
boolean |
isInfoEnabled()
Check whether this category is enabled for the info Level.
|
void |
log(Priority priority,
Object msg)
Log a message with the code level priority.
|
void |
log(Priority priority,
Object message,
Throwable t)
This generic form is intended to be used by wrappers.
|
void |
log(String callerFQCN,
Priority level,
Object message,
Throwable t)
This is the most generic printing method.
|
static void |
shutdown()
Deprecated.
|
protected abstract void |
trace(Object message,
Throwable t) |
void |
warn(Object message)
Log a message object with the WARN Level.
|
void |
warn(Object message,
Throwable t)
|
protected PaxLogger m_delegate
public Category(PaxLogger delegate)
public void assertLog(boolean assertion,
String msg)
assertion parameter is false, then
logs msg as an error statement.
The assert method has been renamed to
assertLog because assert is a language
reserved word in JDK 1.4.
assertion - if false, log the message.msg - The message to print if assertion is
false.public void debug(Object message)
This method first checks if this category is DEBUG enabled
by comparing the level of this category with the
DEBUG level. If this category is DEBUG enabled, then it
converts the message object (passed as parameter) to a string by
invoking the appropriate org.apache.log4j.or.ObjectRenderer. It
then proceeds to call all the registered appenders in this category and
also higher in the hierarchy depending on the value of the additivity
flag.
WARNING Note that passing a Throwable to this method will
print the name of the Throwable but no stack trace. To
print a stack trace use the debug(Object,Throwable) form
instead.
message - the message object to log.public void debug(Object message, Throwable t)
DEBUG level including the
stack trace of the Throwablet passed as parameter.
See debug(Object) form for more detailed information.
message - the message object to log.t - the exception to log, including its stack trace.public void error(Object message)
This method first checks if this category is ERROR enabled
by comparing the level of this category with ERROR
Level. If this category is ERROR enabled, then it converts
the message object passed as parameter to a string by invoking the
appropriate org.apache.log4j.or.ObjectRenderer. It proceeds to
call all the registered appenders in this category and also higher in
the hierarchy depending on the value of the additivity flag.
WARNING Note that passing a Throwable to this method will
print the name of the Throwable but no stack trace. To
print a stack trace use the error(Object,Throwable) form
instead.
message - the message object to logpublic void error(Object message, Throwable t)
ERROR level including the
stack trace of the Throwablet passed as parameter.
See error(Object) form for more detailed information.
message - the message object to log.t - the exception to log, including its stack trace.public void fatal(Object message)
This method first checks if this category is FATAL enabled
by comparing the level of this category with FATAL
Level. If the category is FATAL enabled, then it converts
the message object passed as parameter to a string by invoking the
appropriate org.apache.log4j.or.ObjectRenderer. It proceeds to
call all the registered appenders in this category and also higher in
the hierarchy depending on the value of the additivity flag.
WARNING Note that passing a Throwable to this method will
print the name of the Throwable but no stack trace. To print a stack
trace use the fatal(Object,Throwable) form instead.
message - the message object to logpublic void fatal(Object message, Throwable t)
FATAL level including the
stack trace of the Throwablet passed as parameter.
See fatal(Object) for more detailed information.
message - the message object to log.t - the exception to log, including its stack trace.public Level getEffectiveLevel()
The Category class is designed so that this method executes as quickly as possible.
public static Category getInstance(String name)
Logger.getLogger(String) instead.name - of the Logger/Category to return.public static Category getInstance(Class clazz)
Logger.getLogger(Class) instead.clazz - name of the Logger/Category to return.public final String getName()
public void info(Object message)
This method first checks if this category is INFO enabled by
comparing the level of this category with INFO Level.
If the category is INFO enabled, then it converts the
message object passed as parameter to a string by invoking the
appropriate org.apache.log4j.or.ObjectRenderer. It proceeds to
call all the registered appenders in this category and also higher in
the hierarchy depending on the value of the additivity flag.
WARNING Note that passing a Throwable to this method will
print the name of the Throwable but no stack trace. To print a stack
trace use the info(Object,Throwable) form instead.
message - the message object to logpublic void info(Object message, Throwable t)
INFO level including the stack
trace of the Throwablet passed as parameter.
See info(Object) for more detailed information.
message - the message object to log.t - the exception to log, including its stack trace.public boolean isDebugEnabled()
DEBUG Level.
This function is intended to lessen the computational cost of disabled log debug statements.
For some cat Category object, when you write,
cat.debug("This is entry number: " + i );
You incur the cost constructing the message, concatenatiion in this case, regardless of whether the message is logged or not.
If you are worried about speed, then you should write
if(cat.isDebugEnabled()) {
cat.debug("This is entry number: " + i );
}
This way you will not incur the cost of parameter construction if
debugging is disabled for cat. On the other hand, if the
cat is debug enabled, you will incur the cost of evaluating
whether the category is debug enabled twice. Once in
isDebugEnabled and once in the debug. This is
an insignificant overhead since evaluating a category takes about 1%% of
the time it takes to actually log.
true if this category is debug enabled,
false otherwise.public boolean isEnabledFor(Priority priority)
Level passed as parameter.
See also isDebugEnabled().level.public boolean isInfoEnabled()
isDebugEnabled().true if this category is enabled for level
info, false otherwise.public void log(Priority priority, Object msg)
priority, - the code level of the messagemsg - the message object to log.public void log(Priority priority, Object message, Throwable t)
priority - priority of log to be generated.message - the message to logt - an Exception to be logged, if any.public void log(String callerFQCN, Priority level, Object message, Throwable t)
callerFQCN - The wrapper class' fully qualified class name.level - The level of the logging request.message - The message of the logging request.t - The throwable of the logging request, may be null.public static void shutdown()
public void warn(Object message)
This method first checks if this category is WARN enabled by
comparing the level of this category with WARN Level.
If the category is WARN enabled, then it converts the
message object passed as parameter to a string by invoking the
appropriate org.apache.log4j.or.ObjectRenderer. It proceeds to
call all the registered appenders in this category and also higher in
the hieararchy depending on the value of the additivity flag.
WARNING Note that passing a Throwable to this method will
print the name of the Throwable but no stack trace. To print a stack
trace use the warn(Object,Throwable) form instead.
message - the message object to log.public void warn(Object message, Throwable t)
WARN level including the stack trace
of the Throwablet passed as parameter.
See warn(Object) for more detailed information.
message - the message object to log.t - the exception to log, including its stack trace.Copyright © 2006-2015 OPS4J - Open Participation Software for Java. All Rights Reserved.