org.nanoj.util.tinydb

Class TinyDatabase

java.lang.Object

org.nanoj.util.tinydb.TinyDatabase

public class TinyDatabase
extends Object

This class represents a "tiny database" instance
A "tiny database" is a set of "tables" ( based on Java Hashtable instances )
It works as an "in memory database", it can be useful for tests or very small databases
The database dictionary and the database tables are stored in the filesystem by serialization

Since:

v 1.0.3

Author:

Laurent Guerin

Constructor Summary

Constructors

Constructor and Description
TinyDatabase(String sFolder) Constructs a new TinyDatabse located in the given folder

Method Summary

Methods

Modifier and Type	Method and Description
TinyTable	createTable(String sTableName, Class<?> keyClass, Class<?> recordClass) Creates a new table in the database
boolean	dropTable(String sTableName)
static TinyDatabase	getCurrentDatabase() Returns the current database
String	getDatabaseFolder() Returns the database filesystem folder (where the tables are saved as files)
TinyTable	getTable(String sTableName) Returns the table object for the given table name If the table doesn't exist an exception is thrown The table returned is ready to use (its records are loaded)
TinyTable	getTable(String sTableName, boolean mustExist) Returns the table object for the given table name (or null if the table is unknown and 'mustExist' flag = 'false') If a table is returned, it is ready to use (its records are loaded)
String[]	getTableNames() Returns all the table names registered in the database dictionary
void	loadAllTables() Loads all the tables in memory
void	saveAllTables() Saves all the tables in the filesystem

Methods inherited from class java.lang.Object

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

Constructor Detail

TinyDatabase

public TinyDatabase(String sFolder)

Constructs a new TinyDatabse located in the given folder

Parameters:

sFolder -

Method Detail

getDatabaseFolder

public String getDatabaseFolder()

Returns the database filesystem folder (where the tables are saved as files)

Returns:

getCurrentDatabase

public static TinyDatabase getCurrentDatabase()

Returns the current database

Returns:

loadAllTables

public void loadAllTables()

Loads all the tables in memory

saveAllTables

public void saveAllTables()

Saves all the tables in the filesystem

getTableNames

public String[] getTableNames()

Returns all the table names registered in the database dictionary

Returns:

getTable

public TinyTable getTable(String sTableName)

Returns the table object for the given table name
If the table doesn't exist an exception is thrown
The table returned is ready to use (its records are loaded)

Parameters:

sTableName - the table name

Returns:

getTable

public TinyTable getTable(String sTableName,
                 boolean mustExist)

Returns the table object for the given table name (or null if the table is unknown and 'mustExist' flag = 'false')
If a table is returned, it is ready to use (its records are loaded)

Parameters:

sTableName - the table name

mustExist - if true the table must exist (if it doesn't exist an exception is thrown),
if false a null value is returned if the table doesn't exist

Returns:

createTable

public TinyTable createTable(String sTableName,
                    Class<?> keyClass,
                    Class<?> recordClass)

Creates a new table in the database

Parameters:

sTableName - the name of the table

recordClass - the class of the records stored in this table

Returns:

dropTable

public boolean dropTable(String sTableName)