io.grpc.internal.PickFirstLoadBalancerProvider Maven / Gradle / Ivy
/*
* Copyright 2018 The gRPC Authors
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
package io.grpc.internal;
import io.grpc.LoadBalancer;
import io.grpc.LoadBalancerProvider;
import io.grpc.NameResolver.ConfigOrError;
import java.util.Map;
/**
* Provider for the "pick_first" balancing policy.
*
* This provides no load-balancing over the addresses from the {@link NameResolver}. It walks
* down the address list and sticks to the first that works.
*/
public final class PickFirstLoadBalancerProvider extends LoadBalancerProvider {
private static final String NO_CONFIG = "no service config";
@Override
public boolean isAvailable() {
return true;
}
@Override
public int getPriority() {
return 5;
}
@Override
public String getPolicyName() {
return "pick_first";
}
@Override
public LoadBalancer newLoadBalancer(LoadBalancer.Helper helper) {
return new PickFirstLoadBalancer(helper);
}
@Override
public ConfigOrError parseLoadBalancingPolicyConfig(
Map rawLoadBalancingPolicyConfig) {
return ConfigOrError.fromConfig(NO_CONFIG);
}
}