Package io.grpc.grpclb

Class GrpclbLoadBalancerProvider

java.lang.Object

io.grpc.LoadBalancer.Factory

io.grpc.LoadBalancerProvider

io.grpc.grpclb.GrpclbLoadBalancerProvider

@Internal
public final class GrpclbLoadBalancerProvider
extends LoadBalancerProvider

The provider for the "grpclb" balancing policy. This class should not be directly referenced in code. The policy should be accessed through LoadBalancerRegistry.getProvider(java.lang.String) with the name "grpclb".

Constructor Summary

Constructors

Constructor	Description
GrpclbLoadBalancerProvider()

Method Summary

Modifier and Type	Method	Description
java.lang.String	getPolicyName()	Returns the load-balancing policy name associated with this provider, which makes it selectable via LoadBalancerRegistry.getProvider(java.lang.String).
int	getPriority()	A priority, from 0 to 10 that this provider should be used, taking the current environment into consideration.
boolean	isAvailable()	Whether this provider is available for use, taking the current environment into consideration.
LoadBalancer	newLoadBalancer(LoadBalancer.Helper helper)	Creates a LoadBalancer that will be used inside a channel.
NameResolver.ConfigOrError	parseLoadBalancingPolicyConfig(java.util.Map<java.lang.String,?> rawLoadBalancingConfigPolicy)	Parses the config for the Load Balancing policy unpacked from the service config.

Methods inherited from class io.grpc.LoadBalancerProvider

equals, hashCode, toString

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Constructor Detail

GrpclbLoadBalancerProvider

public GrpclbLoadBalancerProvider()

Method Detail

isAvailable

public boolean isAvailable()

Description copied from class: LoadBalancerProvider

Whether this provider is available for use, taking the current environment into consideration. If false, LoadBalancer.Factory.newLoadBalancer(io.grpc.LoadBalancer.Helper) is not safe to be called.

Specified by:

isAvailable in class LoadBalancerProvider

getPriority

public int getPriority()

Description copied from class: LoadBalancerProvider

A priority, from 0 to 10 that this provider should be used, taking the current environment into consideration. 5 should be considered the default, and then tweaked based on environment detection. A priority of 0 does not imply that the provider wouldn't work; just that it should be last in line.

Specified by:

getPriority in class LoadBalancerProvider

getPolicyName

public java.lang.String getPolicyName()

Description copied from class: LoadBalancerProvider

Returns the load-balancing policy name associated with this provider, which makes it selectable via LoadBalancerRegistry.getProvider(java.lang.String). This is called only when the class is loaded. It shouldn't change, and there is no point doing so.

The policy name should consist of only lower case letters letters, underscore and digits, and can only start with letters.

Specified by:

getPolicyName in class LoadBalancerProvider

newLoadBalancer

public LoadBalancer newLoadBalancer(LoadBalancer.Helper helper)

Description copied from class: LoadBalancer.Factory

Creates a LoadBalancer that will be used inside a channel.

Specified by:

newLoadBalancer in class LoadBalancer.Factory

parseLoadBalancingPolicyConfig

public NameResolver.ConfigOrError parseLoadBalancingPolicyConfig(java.util.Map<java.lang.String,?> rawLoadBalancingConfigPolicy)

Description copied from class: LoadBalancerProvider

Parses the config for the Load Balancing policy unpacked from the service config. This will return a NameResolver.ConfigOrError which contains either the successfully parsed config, or the Status representing the failure to parse. Implementations are expected to not throw exceptions but return a Status representing the failure. If successful, the load balancing policy config should be immutable.

Overrides:

parseLoadBalancingPolicyConfig in class LoadBalancerProvider

Parameters:

rawLoadBalancingConfigPolicy - The Map representation of the load balancing policy choice.

Returns:

a tuple of the fully parsed and validated balancer configuration, else the Status.

See Also:

A24-lb-policy-config.md