io.netty.channel.pool.ChannelHealthChecker Maven / Gradle / Ivy
/*
* Copyright 2015 The Netty Project
*
* The Netty Project licenses this file to you 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.netty.channel.pool;
import io.netty.channel.Channel;
import io.netty.channel.EventLoop;
import io.netty.util.concurrent.Future;
import io.netty.util.concurrent.Promise;
/**
* Called before a {@link Channel} will be returned via {@link ChannelPool#acquire()} or
* {@link ChannelPool#acquire(Promise)}.
*/
public interface ChannelHealthChecker {
/**
* {@link ChannelHealthChecker} implementation that checks if {@link Channel#isActive()} returns {@code true}.
*/
ChannelHealthChecker ACTIVE = new ChannelHealthChecker() {
@Override
public Future isHealthy(Channel channel) {
EventLoop loop = channel.eventLoop();
return channel.isActive()? loop.newSucceededFuture(Boolean.TRUE) : loop.newSucceededFuture(Boolean.FALSE);
}
};
/**
* Check if the given channel is healthy which means it can be used. The returned {@link Future} is notified once
* the check is complete. If notified with {@link Boolean#TRUE} it can be used {@link Boolean#FALSE} otherwise.
*
* This method will be called by the {@link EventLoop} of the {@link Channel}.
*/
Future isHealthy(Channel channel);
}