org.foxlabs.util.resource

Class Service

java.lang.Object

org.foxlabs.util.resource.Service

public abstract class Service
extends Object

This class used to load service providers (Java Service Provider Interface).

Author:

Fox Mulder

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected static class	Service.ProviderClassItr<P> Lazy iterator over provider classes.
protected static class	Service.ProviderItr<P> Lazy iterator over service provider instances.

Field Summary

Fields

Modifier and Type	Field and Description
static String	DIRECTORY SPI resources directory.

Method Summary

Methods

Modifier and Type	Method and Description
static <P> Iterator<P>	lookup(Class<P> category) Searches for service provider classes of the specified category and returns iterator over their instances.
static <P> Iterator<P>	lookup(Class<P> category, ClassLoader cl) Searches for service provider classes of the specified category using the specified class loader and returns iterator over their instances.
static <P> Iterator<Class<? extends P>>	lookupClasses(Class<P> category) Searches for service provider classes of the specified category and returns iterator over them.
static <P> Iterator<Class<? extends P>>	lookupClasses(Class<P> category, ClassLoader cl) Searches for service provider classes of the specified category using the specified class loader and returns iterator over them.
static <P> P	lookupFirst(Class<P> category) Searches for service provider classes of the specified category and returns first service provider instance.
static <P> P	lookupFirst(Class<P> category, ClassLoader cl) Searches for service provider classes of the specified category using the specified class loader and returns first service provider instance.

Methods inherited from class java.lang.Object

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

Field Detail

DIRECTORY

public static final String DIRECTORY

SPI resources directory.

See Also:

Constant Field Values

Method Detail

lookup

public static <P> Iterator<P> lookup(Class<P> category)

Searches for service provider classes of the specified category and returns iterator over their instances.

Parameters:

category - Service provider category to search.

Returns:

Iterator over service provider instances of the specified category.

Throws:

ResourceError - if an error occured when reading SPI resources.

See Also:

lookup(Class, ClassLoader)

lookup

public static <P> Iterator<P> lookup(Class<P> category,
                     ClassLoader cl)

Searches for service provider classes of the specified category using the specified class loader and returns iterator over their instances.

Parameters:

category - Service provider category to search.

cl - Class loader to be used for service provider class loading.

Returns:

Iterator over service provider instances of the specified category.

Throws:

ResourceError - if an error occured when reading SPI resources.

lookupFirst

public static <P> P lookupFirst(Class<P> category)

Searches for service provider classes of the specified category and returns first service provider instance.

Parameters:

category - Service provider category to search.

Returns:

First service provider instance or null if there are no service provider classes found.

Throws:

ResourceError - if an error occured when reading SPI resources.

See Also:

lookupFirst(Class, ClassLoader)

lookupFirst

public static <P> P lookupFirst(Class<P> category,
                ClassLoader cl)

Searches for service provider classes of the specified category using the specified class loader and returns first service provider instance.

Parameters:

category - Service provider category to search.

cl - Class loader to be used for service provider class loading.

Returns:

First service provider instance or null if there are no service provider classes found.

Throws:

ResourceError - if an error occured when reading SPI resources.

lookupClasses

public static <P> Iterator<Class<? extends P>> lookupClasses(Class<P> category)

Searches for service provider classes of the specified category and returns iterator over them.

Parameters:

category - Service provider category to search.

Returns:

Iterator over service provider classes of the specified category.

Throws:

ResourceError - if an error occured when reading SPI resources.

See Also:

lookupClasses(Class, ClassLoader)

lookupClasses

public static <P> Iterator<Class<? extends P>> lookupClasses(Class<P> category,
                                             ClassLoader cl)

Searches for service provider classes of the specified category using the specified class loader and returns iterator over them.

Parameters:

category - Service provider category to search.

cl - Class loader to be used for service provider class loading.

Returns:

Iterator over service provider classes of the specified category.

Throws:

ResourceError - if an error occured when reading SPI resources.