jcckit.util

Class Factory

java.lang.Object

jcckit.util.Factory

public class Factory
extends Object

General purpose factory method based on ConfigParameters and Java's Reflection API.

Author:

Franz-Josef Elmer

Field Summary

Fields

Modifier and Type	Field and Description
static String	CLASS_NAME_KEY The constant defining the key className.

Method Summary

Modifier and Type	Method and Description
static Object	create(ConfigParameters configParameters) Creates an object based on the specified configuration parameters.
static Object	create(ConfigParameters configParameters, String defaultClassName) Creates an object based on the specified configuration parameters and default class name.
static Object	create(String className) Creates an instance of the specified class.
static Object	createOrGet(ConfigParameters configParameters, Object defaultObject) Creates an object based on the specified configuration parameters or returns the default object.

Methods inherited from class java.lang.Object

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

Field Detail

CLASS_NAME_KEY

public static final String CLASS_NAME_KEY

The constant defining the key className.

See Also:

Constant Field Values

Method Detail

create

public static Object create(String className)

Creates an instance of the specified class.

Parameters:

className - Fully-qualified name of a class with a default constructor.

Returns:

a new instance.

Throws:

IllegalArgumentException - if the instance could be created.

create

public static Object create(ConfigParameters configParameters)

Creates an object based on the specified configuration parameters. The class of the object is determined by the parameter with the key CLASS_NAME_KEY. The constructor with a single argument of the type ConfigParameter is invoked with the argument configParameters. If such a constructor does not exists the default constructor is invoked. If neither of these constructors exist a FactoryException is thrown.

Parameters:

configParameters - Configuration parameters.

Returns:

the newly created object.

Throws:

IllegalArgumentException - if key className is missing.

FactoryException - wrapping any kind of exception or error occured.

create

public static Object create(ConfigParameters configParameters,
                            String defaultClassName)

Creates an object based on the specified configuration parameters and default class name. If the parameter with the key CLASS_NAME_KEY is missed in configParameters defaultClassName is used. Otherwise it works as create(jcckit.util.ConfigParameters).

Parameters:

configParameters - Configuration parameters.

defaultClassName - Default class name.

Returns:

the newly created object.

Throws:

FactoryException - wrapping any kind of exception or error occured.

createOrGet

public static Object createOrGet(ConfigParameters configParameters,
                                 Object defaultObject)

Creates an object based on the specified configuration parameters or returns the default object. This method behaves as create(jcckit.util.ConfigParameters), except that is does not throw an IllegalArgumentException if key className is missing. Instead defaultObject is returned.