wns::logger Namespace Reference

Logging subsystem of WNS. More...

Classes
class	CerrOutput
class	ConsoleFormat
class	CoutOutput
class	DelimiterFormat
	Formats messages, elements are separated by a delimiter. More...
class	FileOutput
class	FormatStrategy
class	Logger
	Writes Message to logger::Master. More...
class	Master
	Base class for logging in WNS. More...
class	Message
	Messages are used in conjunction with Logger instead of simple "cout-Logging". More...
class	OutputStrategy
struct	RawMessage
class	SQLiteFormat
	Format message to be imported into SQLite. More...
class	XMLFormat
	Formats messages in XML. More...
Typedefs
typedef PyConfigViewCreator < FormatStrategy, FormatStrategy >	FormatStrategyCreator
typedef StaticFactory < FormatStrategyCreator >	FormatStrategyFactory
typedef Creator < OutputStrategy, OutputStrategy >	OutputStrategyCreator
typedef StaticFactory < OutputStrategyCreator >	OutputStrategyFactory
Enumerations
enum	Level {   OFF = 0, QUIET = 1, NORMAL = 2, VERBOSE = 3,   MAXLEVEL }
	ENUM for better readability of logger Levels. More...

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Detailed Description

WNS provides a nice logging system that supports Messages with priorities. This makes the use of "cout-Logging" obsolete. It works as follows:

1. Create an empty Message "m"
2. Fill "m" with information
3. Use a Logger to send Message to MasterLogger
   1. If the Logger is disabled the Message will be dropped
   2. If the Logger is enabled the Message is sent to the MasterLogger
      1. If the MasterLogger is enabled and the priority of the Message is higher than the global logging priority the Message is processed
      2. If the MasterLogger is disabled the Message is dropped

The logging has some useful features:

1. Each Logger can be enabled and disabled
2. Message objects may be used like streams
3. Supports different MasterLoggers (ConsoleLogger, FileLogger, NetLogger, ...)
4. The whole logging system can be disabled at compile time by defining WNS_NO_LOGGING. If the logging system is disabled there is no more runtime overhead.

Motivation

For the development and usage of simulation tools it is indispensable to have a mechanism for logging of (debugging) information about the current state/actions of the programm. As an example consider a mobile station appliying power control to its links. You want to see, if your power control works, hence you insert the following line in your power control algorithm:

   class Transmitter {
   public:
    ....
    void powerControl()
    {
        ...
        std::cout << "Set new power to: " << newPower << " dBm\n";
    }
    ...
   };

Every time the algorithm is executed you will see an output like this:

   Set new power to: 32 dBm
   Set new power to: 33 dBm
   Set new power to: 34 dBm
   Set new power to: 33 dBm
   

This is quite nice if you have only few logging messages. But with an increasing number of entities logging in such a way a number of problems appear:

1. You can't see which entity (station) has generated the output.

2. The simulation time when the output was generated is often of interest.

3. You might want to disable certain logging output because it bloats your ouput with (at this moment) useless information.

4. You need this output only if you're currently debugging your simulator. In case your simulating (what you should aim at) this output is not only useless, but it slows your simulation significantly down.

5. You might want to redirect your logging output to something different but stdout.

Usage

Therefore a logging system has been created which tackles all these issues. In the following the usage of the system will be explained.

In order to use the logging service you need to know two things:

1. How is the stuff used in C++?

2. How is the stuff configured in PyConfig?

More to come ;)

Todo:

Finalize documentation ... :)

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Typedef Documentation

typedef PyConfigViewCreator<FormatStrategy, FormatStrategy> wns::logger::FormatStrategyCreator

Definition at line 69 of file FormatStrategy.hpp.

typedef StaticFactory<FormatStrategyCreator> wns::logger::FormatStrategyFactory

Definition at line 70 of file FormatStrategy.hpp.

typedef Creator<OutputStrategy, OutputStrategy> wns::logger::OutputStrategyCreator

Definition at line 46 of file OutputStrategy.hpp.

typedef StaticFactory<OutputStrategyCreator> wns::logger::OutputStrategyFactory

Definition at line 47 of file OutputStrategy.hpp.

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Enumeration Type Documentation

enum wns::logger::Level

Enumerator:

OFF
QUIET
NORMAL
VERBOSE
MAXLEVEL

Definition at line 79 of file Logger.hpp.