ServiceCache.java

/**
 * The MIT License
 * Copyright (c) 2014-2016 Ilkka Seppälä
 *
 * Permission is hereby granted, free of charge, to any person obtaining a copy
 * of this software and associated documentation files (the "Software"), to deal
 * in the Software without restriction, including without limitation the rights
 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
 * copies of the Software, and to permit persons to whom the Software is
 * furnished to do so, subject to the following conditions:
 *
 * The above copyright notice and this permission notice shall be included in
 * all copies or substantial portions of the Software.
 *
 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
 * THE SOFTWARE.
 */
package com.iluwatar.servicelocator;

import org.slf4j.Logger;
import org.slf4j.LoggerFactory;

import java.util.HashMap;
import java.util.Map;

/**
 * The service cache implementation which will cache services that are being created. On first hit,
 * the cache will be empty and thus any service that is being requested, will be created fresh and
 * then placed into the cache map. On next hit, if same service name will be requested, it will be
 * returned from the cache
 *
 * @author saifasif
 */
public class ServiceCache {

  private static final Logger LOGGER = LoggerFactory.getLogger(ServiceCache.class);

  private final Map<String, Service> serviceCache;

  public ServiceCache() {
    serviceCache = new HashMap<>();
  }

  /**
   * Get the service from the cache. null if no service is found matching the name
   *
   * @param serviceName a string
   * @return {@link Service}
   */
  public Service getService(String serviceName) {
    Service cachedService = null;
    for (String serviceJndiName : serviceCache.keySet()) {
      if (serviceJndiName.equals(serviceName)) {
        cachedService = serviceCache.get(serviceJndiName);
        LOGGER.info("(cache call) Fetched service {}({}) from cache... !",
                cachedService.getName(), cachedService.getId());
      }
    }
    return cachedService;
  }

  /**
   * Adds the service into the cache map
   *
   * @param newService a {@link Service}
   */
  public void addService(Service newService) {
    serviceCache.put(newService.getName(), newService);
  }
}