Package org.apache.lucene.util

Class NamedSPILoader<S extends NamedSPILoader.NamedSPI>

java.lang.Object

org.apache.lucene.util.NamedSPILoader<S>

All Implemented Interfaces:

java.lang.Iterable<S>

public final class NamedSPILoader<S extends NamedSPILoader.NamedSPI>
extends java.lang.Object
implements java.lang.Iterable<S>

Helper class for loading named SPIs from classpath (e.g. Codec, PostingsFormat).

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static interface	NamedSPILoader.NamedSPI	Interface to support lookup(String) by name.

Constructor Summary

Constructors

Constructor	Description
NamedSPILoader(java.lang.Class<S> clazz)
NamedSPILoader(java.lang.Class<S> clazz, java.lang.ClassLoader classloader)

Method Summary

Modifier and Type	Method	Description
java.util.Set<java.lang.String>	availableServices()
static void	checkServiceName(java.lang.String name)	Validates that a service name meets the requirements of NamedSPILoader.NamedSPI
java.util.Iterator<S>	iterator()
S	lookup(java.lang.String name)
void	reload(java.lang.ClassLoader classloader)	Reloads the internal SPI list from the given ClassLoader.

Methods inherited from class java.lang.Object

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

Methods inherited from interface java.lang.Iterable

forEach, spliterator

Constructor Detail

NamedSPILoader

public NamedSPILoader(java.lang.Class<S> clazz)

NamedSPILoader

public NamedSPILoader(java.lang.Class<S> clazz,
                      java.lang.ClassLoader classloader)

Method Detail

reload

public void reload(java.lang.ClassLoader classloader)

Reloads the internal SPI list from the given ClassLoader. Changes to the service list are visible after the method ends, all iterators (iterator(),...) stay consistent.

NOTE: Only new service providers are added, existing ones are never removed or replaced.

This method is expensive and should only be called for discovery of new service providers on the given classpath/classloader!

checkServiceName

public static void checkServiceName(java.lang.String name)

Validates that a service name meets the requirements of NamedSPILoader.NamedSPI

lookup

public S lookup(java.lang.String name)

availableServices

public java.util.Set<java.lang.String> availableServices()

iterator

public java.util.Iterator<S> iterator()

Specified by:

iterator in interface java.lang.Iterable<S extends NamedSPILoader.NamedSPI>