org.apache.clerezza.implementation.literal

Class LiteralFactory

java.lang.Object

org.apache.clerezza.implementation.literal.LiteralFactory

Direct Known Subclasses:

SimpleLiteralFactory

public abstract class LiteralFactory
extends Object

This class provides methods to convert java objects to typed literals and vice versa. While the default implementation will provide literal objects storing the data's lexical form in memory, other implementations may create literal optimized for processing within the store.

Note: this class uses the notion of "Convertor" (in the Exception naming), but does not currently provide a mechanism to register such Convertors. An implementation is said to provide Convertors for the types it supports.

Since:

0.3

Author:

reto

Constructor Summary

Constructors

Constructor and Description
LiteralFactory()

Method Summary

Modifier and Type	Method and Description
abstract <T> T	createObject(Class<T> type, Literal literal) Converts a literal to an instance of the specified class
abstract Literal	createTypedLiteral(Object value) Create a typed literal for the specified object
static LiteralFactory	getInstance() Get a LiteralFactory.
static void	setInstance(LiteralFactory instance) Set the instance returned by getInstance.

Methods inherited from class java.lang.Object

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

Constructor Detail

LiteralFactory

public LiteralFactory()

Method Detail

getInstance

public static LiteralFactory getInstance()

Get a LiteralFactory. If this has not been set using setInstance it returns an instance of org.apache.clerezza.model.impl.SimpleLiteralFactory.

Returns:

a concrete LiteralFactory

setInstance

public static void setInstance(LiteralFactory instance)

Set the instance returned by getInstance.

Parameters:

instance - the new default LiteralFactory

createTypedLiteral

public abstract Literal createTypedLiteral(Object value)
                                    throws NoConvertorException

Create a typed literal for the specified object

Parameters:

value - the value of the literal to be created

Returns:

a TypedLiteral representing the value

Throws:

NoConvertorException - thrown if value is of an invalid type

createObject

public abstract <T> T createObject(Class<T> type,
                                   Literal literal)
                            throws NoConvertorException,
                                   InvalidLiteralTypeException

Converts a literal to an instance of the specified class

Type Parameters:

T -

Parameters:

type - the Class of the returned object

literal - the literal to be converted

Returns:

a java object representing the value of the literal

Throws:

NoConvertorException - thrown if type is unsupported

InvalidLiteralTypeException - if the literal type doesn't match the requested java type