Package io.grpc

Class LoadBalancerRegistry

java.lang.Object

io.grpc.LoadBalancerRegistry

@ExperimentalApi("https://github.com/grpc/grpc-java/issues/1771")
@ThreadSafe
public final class LoadBalancerRegistry
extends java.lang.Object

Registry of LoadBalancerProviders. The default instance loads providers at runtime through the Java service provider mechanism.

Since:

1.17.0

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
private static class	LoadBalancerRegistry.LoadBalancerPriorityAccessor

Field Summary

Fields

Modifier and Type	Field	Description
private java.util.LinkedHashSet<LoadBalancerProvider>	allProviders
private java.util.LinkedHashMap<java.lang.String,LoadBalancerProvider>	effectiveProviders
private static java.lang.Iterable<java.lang.Class<?>>	HARDCODED_CLASSES
private static LoadBalancerRegistry	instance
private static java.util.logging.Logger	logger

Constructor Summary

Constructors

Constructor	Description
LoadBalancerRegistry()

Method Summary

Modifier and Type	Method	Description
private void	addProvider(LoadBalancerProvider provider)
void	deregister(LoadBalancerProvider provider)	Deregisters a provider.
static LoadBalancerRegistry	getDefaultRegistry()	Returns the default registry that loads providers via the Java service loader mechanism.
(package private) static java.util.List<java.lang.Class<?>>	getHardCodedClasses()
LoadBalancerProvider	getProvider(java.lang.String policy)	Returns the effective provider for the given load-balancing policy, or null if no suitable provider can be found.
(package private) java.util.Map<java.lang.String,LoadBalancerProvider>	providers()	Returns effective providers in a new map.
private void	refreshProviderMap()
void	register(LoadBalancerProvider provider)	Register a provider.

Methods inherited from class java.lang.Object

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

Field Detail

logger

private static final java.util.logging.Logger logger

instance

private static LoadBalancerRegistry instance

HARDCODED_CLASSES

private static final java.lang.Iterable<java.lang.Class<?>> HARDCODED_CLASSES

allProviders

private final java.util.LinkedHashSet<LoadBalancerProvider> allProviders

effectiveProviders

private final java.util.LinkedHashMap<java.lang.String,LoadBalancerProvider> effectiveProviders

Constructor Detail

LoadBalancerRegistry

public LoadBalancerRegistry()

Method Detail

register

public void register(LoadBalancerProvider provider)

Register a provider.

If the provider's isAvailable() returns false, this method will throw IllegalArgumentException.

If more than one provider with the same policy name are registered, the one with the highest priority will be effective. If there are more than one name-sake providers rank the highest priority, the one registered first will be effective.

addProvider

private void addProvider(LoadBalancerProvider provider)

deregister

public void deregister(LoadBalancerProvider provider)

Deregisters a provider. No-op if the provider is not in the registry. If there are more than one providers with the same policy name as the deregistered one in the registry, one of them will become the effective provider for that policy, per the rule documented in register(io.grpc.LoadBalancerProvider).

Parameters:

provider - the provider that was added to the register via register(io.grpc.LoadBalancerProvider).

refreshProviderMap

private void refreshProviderMap()

getDefaultRegistry

public static LoadBalancerRegistry getDefaultRegistry()

Returns the default registry that loads providers via the Java service loader mechanism.

getProvider

@Nullable
public LoadBalancerProvider getProvider(java.lang.String policy)

Returns the effective provider for the given load-balancing policy, or null if no suitable provider can be found. Each provider declares its policy name via LoadBalancerProvider.getPolicyName().

providers

java.util.Map<java.lang.String,LoadBalancerProvider> providers()

Returns effective providers in a new map.

getHardCodedClasses

static java.util.List<java.lang.Class<?>> getHardCodedClasses()