Table of Contents

1. Description
2. The Library
   1. Logger
   2. Data-structure
      1. AVL Tree
      2. ObjectTable
   3. Data-type
      1. Cursor
3. License

Description

Personal Java library or reusable components.

The Library

---

Logger

eadjlib.logger

Customisable logging system with different formatting and output options.

Important note

It is recommended to write a toString() method to all classes. This is what the logger will output when you pass it instances of those classes.

Interface:

void log( Object... objects ); //Standard message

void log_Fatal( Object... objects ); //Fatal event

void log_Error( Object... objects ); //Error

void log_Warning( Object... objects ); //Warning

void log_Debug( Object... objects ); //Debug

void log_Trace( Object... objects ); //For tracing

void log_Exception( Exception e ); //For pushing exception to the log after an error

Usage

Logging messages:

Logger log = Logger.getLoggerInstance( Myclass.class.getName() );

log.log( "Testing ", 1, ", " , 2, ", ", 3, ", and some more..." );

Logging an exception:

When catching an exception and logging it is required the "log_Exception" call can be used to add the stacktrace to the log after a previous message detailing the event.

e.g.:

try {
    /** some stuff that raises an exception **/ 
} catch ( Exception e ) { 
    log.log_error( "An exception was raise because..." ),
    log.log_Exception( e )
}

Configuration

The log_config.cfg file is created during the first run of the logger if it isn't there already. Inside you can set your options for the logging like the log level and outputs you want to see the log messages in.

GUI Viewer

To create a viewer for the log:

1. Add OUTPUT=<WINDOW,window_name> to the log's config file,
2. Create a class that implements Log_Window_Interface to pass the messages from the log to your viewer,
3. Call connectView( Log_Window_Interface ) with your implemented class as an argument to connect the logger to the class.

An example implementation of a GUI log viewer using JavaFX is available here.

Data-structure

AVL Tree

AVLTree<K,V>

Balanced binary tree where the heights of every node differ at most by +/- 1.

ObjectTable

ObjectTable

Object table for caching/transporting SQL result sets. Elements are added in sequential order left-to-right, row-by-row from the top.

Data-type

Cursor

Cursor

Tuple container that holds row and column indices.

License

This software is released under the GNU General Public License 2 license.

Please reference when used in project and/or research and/or papers and/or integrated in production code (i.e.: DBAD).

Copyright E. A. Davison 2016-17.