io.grpc.LoadBalancerProvider 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;
import com.google.common.base.MoreObjects;
/**
* Provider of {@link LoadBalancer}s. Each provider is bounded to a load-balancing policy name.
*
* @since 1.17.0
*/
@ExperimentalApi("https://github.com/grpc/grpc-java/issues/1771")
public abstract class LoadBalancerProvider extends LoadBalancer.Factory {
/**
* Whether this provider is available for use, taking the current environment into consideration.
* If {@code false}, {@link #newLoadBalancer} is not safe to be called.
*/
public abstract boolean isAvailable();
/**
* 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.
*/
public abstract int getPriority();
/**
* Returns the load-balancing policy name associated with this provider, which makes it selectable
* via {@link LoadBalancerRegistry#getProvider}. 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.
*/
public abstract String getPolicyName();
@Override
public final String toString() {
return MoreObjects.toStringHelper(this)
.add("policy", getPolicyName())
.add("priority", getPriority())
.add("available", isAvailable())
.toString();
}
/**
* Uses identity equality.
*/
@Override
public final boolean equals(Object other) {
return this == other;
}
@Override
public final int hashCode() {
return super.hashCode();
}
}