p2p.storage
Class StorageFactory

java.lang.Object
  p2p.storage.StorageFactory

public abstract class StorageFactory
extends Object

Abstract Factory (GoF) that defines the operations that create various objects of the Storage subsystem. It is recommended to instantiate such types only through a concrete implementation of this factory to avoid hard-coding direct references to them. This class provides static methods to find concrete factories using the reflection API to further decouple the subsystem from its client.

Version:

1.0.0

Author:

@author Roman Schmidt

Constructor Summary

StorageFactory()

Method Summary

abstract DataItem	createDataItem(Type type, Object data) Create a DataItem instance compatible with the Storage implementation.
abstract Query	createQuery(Type type, String queryString) Create a Query instance compatible with the Storage implementation.
abstract Query	createQuery(Type type, String lowerBound, String higherBound) Create a Query instance compatible with the Storage implementation.
abstract Storage	createStorage(P2P p2p) Create the concrete Storage implementation.
abstract Type	createType(String type) Creates a Type instance compatible with the Storage implementation.
abstract void	registerTypeHandler(Type type, TypeHandler handler) Registers a Type Handler instance for a given Type.

Methods inherited from class java.lang.Object

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

Constructor Detail

StorageFactory

public StorageFactory()

Method Detail

createDataItem

public abstract DataItem createDataItem(Type type,
                                        Object data)
                                 throws NoSuchTypeException

Create a DataItem instance compatible with the Storage implementation.

Parameters:

type - the data item's type

data - the encapsulated data

Returns:

a DataItem instance

Throws:

NoSuchTypeException - if the provided Type is unknown.

createQuery

public abstract Query createQuery(Type type,
                                  String queryString)
                           throws NoSuchTypeException

Create a Query instance compatible with the Storage implementation.

Parameters:

type - the Type of items the query is for

queryString - the string object that defines the query

Returns:

a Query instance

Throws:

NoSuchTypeException - if the provided Type is unknown.

createQuery

public abstract Query createQuery(Type type,
                                  String lowerBound,
                                  String higherBound)
                           throws NoSuchTypeException

Create a Query instance compatible with the Storage implementation.

Parameters:

type - the Type of items the query is for

lowerBound - the string object that defines the lower bound of the query

higherBound - the string object that defines the higher bound of the query

Returns:

a Query instance

Throws:

NoSuchTypeException - if the provided Type is unknown.

createStorage

public abstract Storage createStorage(P2P p2p)

Create the concrete Storage implementation.

Parameters:

p2p - the P2P implementation.

Returns:

the Storage implementation.

createType

public abstract Type createType(String type)

Creates a Type instance compatible with the Storage implementation.

Parameters:

type - an application-specific type to encapsulate

Returns:

a Type instance

registerTypeHandler

public abstract void registerTypeHandler(Type type,
                                         TypeHandler handler)
                                  throws NoSuchTypeException

Registers a Type Handler instance for a given Type.

Parameters:

type - an application-specific type to encapsulate

handler - an application-specific type handler to encapsulate

Throws:

NoSuchTypeException - if the provided Type is unknown.