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.solr.search;
  
  
  import org.apache.lucene.index.IndexReader;
  import org.apache.lucene.search.Collector;
  import org.apache.lucene.search.Scorer;
  
  import java.io.IOException;
  
  
  /** A simple delegating collector where one can set the delegate after creation */
  public class DelegatingCollector extends Collector {
    static int setLastDelegateCount; // for testing purposes only to determine the number of times a delegating collector chain was used
  
    protected Collector delegate;
    protected Scorer scorer;
    protected IndexReader reader;
    protected int docBase;
  
    public Collector getDelegate() {
      return delegate;
    }
  
    public void setDelegate(Collector delegate) {
      this.delegate = delegate;
    }
  
    /** Sets the last delegate in a chain of DelegatingCollectors */
    public void setLastDelegate(Collector delegate) {
      DelegatingCollector ptr = this;
      for(; ptr.getDelegate() instanceof DelegatingCollector; ptr = (DelegatingCollector)ptr.getDelegate());
      ptr.setDelegate(delegate);
      setLastDelegateCount++;
    }
  
    @Override
    public void setScorer(Scorer scorer) throws IOException {
      this.scorer = scorer;
      delegate.setScorer(scorer);
    }
  
    @Override
    public void collect(int doc) throws IOException {
      delegate.collect(doc);
    }
  
    @Override
    public void setNextReader(IndexReader reader, int docBase) throws IOException {
      this.reader = reader;
      this.docBase = docBase;
      delegate.setNextReader(reader, docBase);
    }
  
    @Override
    public boolean acceptsDocsOutOfOrder() {
      return delegate.acceptsDocsOutOfOrder();
    }
  }
  