/*
 * Licensed to the Apache Software Foundation (ASF) under one or more
 * contributor license agreements.  See the NOTICE file distributed with
 * this work for additional information regarding copyright ownership.
 * The ASF 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 org.apache.dubbo.config.integration.multiple;

/**
 * This interface to store the given type instance in multiple registry center.
 * @param <T> The type to store
 */
public interface Storage <T>{

    /**
     * Gets the stored instance with the given host and port.
     * @param host the host in the register center.
     * @param port the port in the register center.
     * @return the stored instance.
     */
    T get(String host, int port);

    /**
     * Sets the stored instance with the given host and port as key.
     * @param host the host in the register center.
     * @param port the port in the register center.
     * @param value the instance to store.
     */
    void put(String host, int port, T value);

    /**
     * Checks if the instance exists with the given host and port.
     * @param host the host in the register center.
     * @param port the port in the register center.
     * @return {@code true} if the instance exists with the given host and port, otherwise {@code false}
     */
    boolean contains(String host, int port);

    /**
     * Returns the size of all stored values.
     */
    int size();

    /**
     * Clear all data.
     */
    void clear();
}
