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
   *
   *     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.aliyun.oss.common.auth;
  
  import com.aliyun.oss.common.auth.Credentials;
  import com.aliyun.oss.common.auth.CredentialsProvider;
  import com.aliyun.oss.common.utils.AuthUtils;
  import com.aliyun.oss.common.utils.LogUtils;
  import com.aliyuncs.exceptions.ClientException;
  
  public class CustomSessionCredentialsProvider implements CredentialsProvider {
  
      public CustomSessionCredentialsProvider(String ossAuthServerHost) {
          this.fetcher = new CustomSessionCredentialsFetcher(ossAuthServerHost);
      }
      
      public CustomSessionCredentialsProvider withCredentialsFetcher(CustomSessionCredentialsFetcher fetcher) {
          this.fetcher = fetcher;
          return this;
      }
  
      @Override
      public void setCredentials(Credentials creds) {
  
      }
  
      @Override
      public Credentials getCredentials() {        
          if (credentials == null || credentials.willSoonExpire()) {
              synchronized (this) {
                  if (credentials == null || credentials.willSoonExpire()) {
                      try {
                          credentials = (BasicCredentials) fetcher.fetch(maxRetryTimes);
                      } catch (ClientException e) {
                          LogUtils.logException("OssAuthCredentialsProvider.fetch Exception:", e);
                          return null;
                      }
                  }
              }
          }
          return credentials;
      }
  
      private BasicCredentials credentials;
      private CustomSessionCredentialsFetcher fetcher;
  
      private int maxRetryTimes = AuthUtils.MAX_ECS_METADATA_FETCH_RETRY_TIMES;
  
  }
  