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
   * <p>
   * http://www.apache.org/licenses/LICENSE-2.0
   * <p>
   * 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.atlas.web.filters;
  
  import org.apache.atlas.repository.graph.AtlasGraphProvider;
  import org.slf4j.Logger;
  import org.slf4j.LoggerFactory;
  import org.springframework.stereotype.Component;
  
  import javax.servlet.Filter;
  import javax.servlet.FilterChain;
  import javax.servlet.FilterConfig;
  import javax.servlet.ServletException;
  import javax.servlet.ServletRequest;
  import javax.servlet.ServletResponse;
  
  import java.io.IOException;
  
  /**
   * Filter that rolls back the stale transaction associated with
   * the thread running this request so that the request will
   * see all of the committed changes.
   *
   */
  @Component
  public class StaleTransactionCleanupFilter implements Filter {
      private static final Logger LOG = LoggerFactory.getLogger(StaleTransactionCleanupFilter.class);
  
      @Override
      public void init(FilterConfig filterConfig) throws ServletException {
          //nothing to do
      }
  
      @Override
      public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain) throws IOException, ServletException {
          LOG.debug("Cleaning stale transactions");
  
          AtlasGraphProvider.getGraphInstance().rollback();
          filterChain.doFilter(request, response);
      }
  
      @Override
      public void destroy() {
          // do nothing
      }
  }
  