ch.agent.crnickl.api

Class SimpleDatabaseManager

java.lang.Object

ch.agent.crnickl.api.SimpleDatabaseManager

public class SimpleDatabaseManager
extends Object

A DatabaseManager sets up a Database using parameters specified in various ways.

Author:

Jean-Paul Vetterli

Constructor Summary

Constructors

Constructor and Description
SimpleDatabaseManager(String parameterString) Construct a simple database manager from a parameter string using default separators and keys.
SimpleDatabaseManager(String dbName, String dbClass, String tdcClass, Map<String,String> parameters) Construct a database manager with a name, a class, and a map of configuration parameters.
SimpleDatabaseManager(String listSeparator, String kvSeparator, String dbNameKey, String dbClassKey, String tdcClassKey, String fileKey, String parameterString) Construct a simple database manager from a parameter string.

Method Summary

Modifier and Type	Method and Description
Database	getDatabase() Return the database corresponding to the configuration.
Map<String,String>	getParameters() Return the map containing configuration parameters.

Methods inherited from class java.lang.Object

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

Constructor Detail

SimpleDatabaseManager

public SimpleDatabaseManager(String dbName,
                             String dbClass,
                             String tdcClass,
                             Map<String,String> parameters)

Construct a database manager with a name, a class, and a map of configuration parameters. If the name of the time domain catalog class is null or empty, a default will be used.

Parameters:

dbName - the name of the database

dbClass - the name of a Database class

tdcClass - the name of a TimeDomainCatalog class or null or empty

parameters - a map of key-value pairs

SimpleDatabaseManager

public SimpleDatabaseManager(String listSeparator,
                             String kvSeparator,
                             String dbNameKey,
                             String dbClassKey,
                             String tdcClassKey,
                             String fileKey,
                             String parameterString)
                      throws T2DBException

Construct a simple database manager from a parameter string. The string is interpreted as a list of key-value pairs. In a key-value pair, everything after the first key-value separator is part of the value and can contain more separators.

Key-value pairs are interpreted as parameters except if the key is a file key. In this case the value is interpreted as an absolute file name. The file contains one key-value pair on each line (with the same key-value separator). Lines can be continued by escaping the end of the line with a backslash. Lines starting with a hash sign are ignored. Files can reference files recursively using the file key mechanism.

The file named by a file key can be followed by key mappings, like this:

file=/foo/bar.txt, x=a, y=b

When key mappings are present, only the mapped keys are extracted from the file (x and y) and they are renamed as specified (a and b). Key remapping is only available inside files, because the list separators are the same at all levels. If the example above were included in a parameter string and not a file, x=a would be interpreted as an independent parameter and not as a key mapping.

The database name and the name of the database class are mandatory. An exception is thrown if the parameter string cannot be parsed successfully.

Parameters:

listSeparator - a regular expression pattern separating list elements

kvSeparator - a regular expression pattern separating a key and a value

dbNameKey - the key for the database name

dbClassKey - the key for the name of the Database class

tdcClassKey - the key for the name of the TimeDomainCatalog class

fileKey - a key naming a file

parameterString - a parameter string

Throws:

T2DBException

SimpleDatabaseManager

public SimpleDatabaseManager(String parameterString)
                      throws T2DBException

Construct a simple database manager from a parameter string using default separators and keys. List elements are separated by a comma, key-value pairs by an equal sign. The database name key is db.name, the database class key is db.class, and the file tag is file.

Parameters:

parameterString - a parameter string

Throws:

T2DBException

Method Detail

getDatabase

public Database getDatabase()
                     throws ch.agent.core.KeyedException

Return the database corresponding to the configuration.

Returns:

a database

Throws:

ch.agent.core.KeyedException

getParameters

public Map<String,String> getParameters()

Return the map containing configuration parameters. Configuration parameters consist of all parameters except the name and the (name of the) class of the database. In principle these parameters are meant for the database but no law forbids to pass arbitrary application parameters through SimpleDatabaseManager.

Returns:

a map with all parameters