content: /*
   * Copyright 1999-2023 Alibaba Group Holding Ltd.
   *
   * Licensed 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.alibaba.nacos.lock.core.reentrant.mutex;
  
  import com.alibaba.nacos.lock.core.reentrant.AbstractAtomicLock;
  import com.alibaba.nacos.lock.model.LockInfo;
  
  import java.util.concurrent.atomic.AtomicReference;
  
  /**
   * use clientId to get lock.
   *
   * @author 985492783@qq.com
   * @date 2023/8/30 1:02
   */
  public class ClientAtomicLock extends AbstractAtomicLock {
      
      private static final String EMPTY = null;
      
      private final AtomicReference<String> state;
      
      private Long expireTimestamp;
      
      public ClientAtomicLock(String key) {
          super(key);
          this.state = new AtomicReference<>(EMPTY);
      }
      
      @Override
      public Boolean tryLock(LockInfo lockInfo) {
          String nacosClientId = (String) lockInfo.getParams().get("nacosClientId");
          if (nacosClientId == null) {
              return false;
          }
          return state.compareAndSet(EMPTY, nacosClientId) || state.get().equals(nacosClientId);
      }
      
      @Override
      public Boolean unLock(LockInfo lockInfo) {
          String nacosClientId = (String) lockInfo.getParams().get("nacosClientId");
          return state.compareAndSet(nacosClientId, EMPTY);
      }
      
      @Override
      public Boolean autoExpire() {
          return System.currentTimeMillis() >= this.expireTimestamp;
      }
      
      @Override
      public Boolean isClear() {
          return state.get() == null || autoExpire();
      }
  }
  