content: /*
   * 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
   *
   *    https://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.bigtop.manager.stack.core.spi;
  
  import lombok.extern.slf4j.Slf4j;
  
  import java.util.Collections;
  import java.util.HashMap;
  import java.util.Map;
  import java.util.ServiceLoader;
  
  @Slf4j
  public class PrioritySPIFactory<T extends PrioritySPI> {
  
      private final Map<String, T> map = new HashMap<>();
  
      public PrioritySPIFactory(Class<T> spiClass) {
          for (T t : ServiceLoader.load(spiClass)) {
              if (map.containsKey(t.getName())) {
                  resolveConflict(t);
              } else {
                  map.put(t.getName(), t);
              }
          }
      }
  
      public Map<String, T> getSPIMap() {
          return Collections.unmodifiableMap(map);
      }
  
      private void resolveConflict(T newSPI) {
          T oldSPI = map.get(newSPI.getName());
  
          if (newSPI.compareTo(oldSPI.getPriority()) == 0) {
              throw new IllegalArgumentException(String.format(
                      "These two spi plugins has conflict identify name with the same priority: %s, %s", oldSPI, newSPI));
          } else if (newSPI.compareTo(oldSPI.getPriority()) > 0) {
              log.info("The {} plugin has high priority, will override {}", newSPI, oldSPI);
              map.put(newSPI.getName(), newSPI);
          } else {
              log.info("The low plugin {} will be skipped", newSPI);
          }
      }
  }
  