io.grpc.ManagedChannel Maven / Gradle / Ivy
/*
* Copyright 2015 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 java.util.concurrent.TimeUnit;
import javax.annotation.concurrent.ThreadSafe;
/**
* A {@link Channel} that provides lifecycle management.
*/
@ThreadSafe
public abstract class ManagedChannel extends Channel {
/**
* Initiates an orderly shutdown in which preexisting calls continue but new calls are immediately
* cancelled.
*
* @return this
* @since 1.0.0
*/
public abstract ManagedChannel shutdown();
/**
* Returns whether the channel is shutdown. Shutdown channels immediately cancel any new calls,
* but may still have some calls being processed.
*
* @see #shutdown()
* @see #isTerminated()
* @since 1.0.0
*/
public abstract boolean isShutdown();
/**
* Returns whether the channel is terminated. Terminated channels have no running calls and
* relevant resources released (like TCP connections).
*
* @see #isShutdown()
* @since 1.0.0
*/
public abstract boolean isTerminated();
/**
* Initiates a forceful shutdown in which preexisting and new calls are cancelled. Although
* forceful, the shutdown process is still not instantaneous; {@link #isTerminated()} will likely
* return {@code false} immediately after this method returns.
*
* @return this
* @since 1.0.0
*/
public abstract ManagedChannel shutdownNow();
/**
* Waits for the channel to become terminated, giving up if the timeout is reached.
*
* @return whether the channel is terminated, as would be done by {@link #isTerminated()}.
* @since 1.0.0
*/
public abstract boolean awaitTermination(long timeout, TimeUnit unit) throws InterruptedException;
/**
* Gets the current connectivity state. Note the result may soon become outdated.
*
* Note that the core library did not provide an implementation of this method until v1.6.1.
*
* @param requestConnection if {@code true}, the channel will try to make a connection if it is
* currently IDLE
* @throws UnsupportedOperationException if not supported by implementation
* @since 1.1.0
*/
@ExperimentalApi("https://github.com/grpc/grpc-java/issues/4359")
public ConnectivityState getState(boolean requestConnection) {
throw new UnsupportedOperationException("Not implemented");
}
/**
* Registers a one-off callback that will be run if the connectivity state of the channel diverges
* from the given {@code source}, which is typically what has just been returned by {@link
* #getState}. If the states are already different, the callback will be called immediately. The
* callback is run in the same executor that runs Call listeners.
*
*
There is an inherent race between the notification to {@code callback} and any call to
* {@code getState()}. There is a similar race between {@code getState()} and a call to {@code
* notifyWhenStateChanged()}. The state can change during those races, so there is not a way to
* see every state transition. "Transitions" to the same state are possible, because intermediate
* states may not have been observed. The API is only reliable in tracking the current
* state.
*
*
Note that the core library did not provide an implementation of this method until v1.6.1.
*
* @param source the assumed current state, typically just returned by {@link #getState}
* @param callback the one-off callback
* @throws UnsupportedOperationException if not supported by implementation
* @since 1.1.0
*/
@ExperimentalApi("https://github.com/grpc/grpc-java/issues/4359")
public void notifyWhenStateChanged(ConnectivityState source, Runnable callback) {
throw new UnsupportedOperationException("Not implemented");
}
/**
* For subchannels that are in TRANSIENT_FAILURE state, short-circuit the backoff timer and make
* them reconnect immediately. May also attempt to invoke {@link NameResolver#refresh}.
*
*
This is primarily intended for Android users, where the network may experience frequent
* temporary drops. Rather than waiting for gRPC's name resolution and reconnect timers to elapse
* before reconnecting, the app may use this method as a mechanism to notify gRPC that the network
* is now available and a reconnection attempt may occur immediately.
*
*
No-op if not supported by the implementation.
*
* @since 1.8.0
*/
@ExperimentalApi("https://github.com/grpc/grpc-java/issues/4056")
public void resetConnectBackoff() {}
/**
* Invoking this method moves the channel into the IDLE state and triggers tear-down of the
* channel's name resolver and load balancer, while still allowing on-going RPCs on the channel to
* continue. New RPCs on the channel will trigger creation of a new connection.
*
*
This is primarily intended for Android users when a device is transitioning from a cellular
* to a wifi connection. The OS will issue a notification that a new network (wifi) has been made
* the default, but for approximately 30 seconds the device will maintain both the cellular
* and wifi connections. Apps may invoke this method to ensure that new RPCs are created using the
* new default wifi network, rather than the soon-to-be-disconnected cellular network.
*
*
No-op if not supported by implementation.
*
* @since 1.11.0
*/
@ExperimentalApi("https://github.com/grpc/grpc-java/issues/4056")
public void enterIdle() {}
}