Client.java

/*
 * Copyright 2016 LINE Corporation
 *
 * LINE Corporation 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 com.linecorp.armeria.client;

import com.linecorp.armeria.common.Request;
import com.linecorp.armeria.common.Response;

/**
 * Sends a {@link Request} to a remote {@link Endpoint}.
 *
 * <p>Note that this interface is not a user's entry point for sending a {@link Request}. It is rather
 * a generic request processor interface implemented by a {@link DecoratingClient}, which intercepts
 * a {@link Request}. A user is supposed to make his or her {@link Request} via the object returned by
 * a {@link ClientBuilder} or {@link Clients}, which usually does not implement this interface.
 *
 * @param <I> the type of the outgoing {@link Request}
 * @param <O> the type of the incoming {@link Response}
 *
 * @see UserClient
 */
@FunctionalInterface
public interface Client<I extends Request, O extends Response> {
    /**
     * Sends a {@link Request} to a remote {@link Endpoint}, as specified in
     * {@link ClientRequestContext#endpoint()}.
     *
     * @return the {@link Response} to the specified {@link Request}
     */
    O execute(ClientRequestContext ctx, I req) throws Exception;
}