io.grpc.services

Class HealthCheckingLoadBalancerUtil

java.lang.Object

io.grpc.services.HealthCheckingLoadBalancerUtil

@ExperimentalApi(value="https://github.com/grpc/grpc-java/issues/5025")
public final class HealthCheckingLoadBalancerUtil
extends Object

Utility for enabling client-side health checking for LoadBalancers.

Method Summary

Modifier and Type	Method and Description
static LoadBalancer	newHealthCheckingLoadBalancer(LoadBalancer.Factory factory, LoadBalancer.Helper helper) Creates a health-checking-capable LoadBalancer.

Methods inherited from class java.lang.Object

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

Method Detail

newHealthCheckingLoadBalancer

public static LoadBalancer newHealthCheckingLoadBalancer(LoadBalancer.Factory factory,
                                                         LoadBalancer.Helper helper)

Creates a health-checking-capable LoadBalancer. This method is used to implement health-checking-capable LoadBalancer.Factorys, which will typically written this way:

 public class HealthCheckingFooLbFactory extends LoadBalancer.Factory {
   // This is the original balancer implementation that doesn't have health checking
   private final LoadBalancer.Factory fooLbFactory;

   ...

   // Returns the health-checking-capable version of FooLb   
   public LoadBalancer newLoadBalancer(Helper helper) {
     return HealthCheckingLoadBalancerUtil.newHealthCheckingLoadBalancer(fooLbFactory, helper);
   }
 }
 

As a requirement for the original LoadBalancer, it must call Helper.createSubchannel() from the Synchronization Context, or createSubchannel() will throw.

Parameters:

factory - the original factory that implements load-balancing logic without health checking

helper - the helper passed to the resulting health-checking LoadBalancer.