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 org.apache.cassandra.index.sasi.analyzer.filter;
  
  /**
   * A single task or set of work to process an input
   * and return a single output. Maintains a link to the
   * next task to be executed after itself
   */
  public abstract class FilterPipelineTask<F, T>
  {
      private String name;
      public FilterPipelineTask<?, ?> next;
  
      protected <K, V> void setLast(String name, FilterPipelineTask<K, V> last)
      {
          if (last == this)
              throw new IllegalArgumentException("provided last task [" + last.name + "] cannot be set to itself");
  
          if (this.next == null)
          {
              this.next = last;
              this.name = name;
          }
          else
          {
              this.next.setLast(name, last);
          }
      }
  
      public abstract T process(F input) throws Exception;
  
      public String getName()
      {
          return name;
      }
  }
  