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.function;
  
  import org.apache.lucene.index.IndexReader;
  import org.apache.lucene.search.Searcher;
  
  import java.io.IOException;
  import java.util.Map;
  
  public abstract class DualFloatFunction extends ValueSource {
    protected final ValueSource a;
    protected final ValueSource b;
  
   /**
     * @param   a  the base.
     * @param   b  the exponent.
     */
    public DualFloatFunction(ValueSource a, ValueSource b) {
      this.a = a;
      this.b = b;
    }
  
    protected abstract String name();
    protected abstract float func(int doc, DocValues aVals, DocValues bVals);
  
    @Override
    public String description() {
      return name() + "(" + a.description() + "," + b.description() + ")";
    }
  
    @Override
    public DocValues getValues(Map context, IndexReader reader) throws IOException {
      final DocValues aVals =  a.getValues(context, reader);
      final DocValues bVals =  b.getValues(context, reader);
      return new DocValues() {
        @Override
        public float floatVal(int doc) {
  	return func(doc, aVals, bVals);
        }
        @Override
        public int intVal(int doc) {
          return (int)floatVal(doc);
        }
        @Override
        public long longVal(int doc) {
          return (long)floatVal(doc);
        }
        @Override
        public double doubleVal(int doc) {
          return floatVal(doc);
        }
        @Override
        public String strVal(int doc) {
          return Float.toString(floatVal(doc));
        }
        @Override
        public String toString(int doc) {
  	return name() + '(' + aVals.toString(doc) + ',' + bVals.toString(doc) + ')';
        }
      };
    }
  
    @Override
    public void createWeight(Map context, Searcher searcher) throws IOException {
      a.createWeight(context,searcher);
      b.createWeight(context,searcher);
    }
  
    @Override
    public int hashCode() {
      int h = a.hashCode();
      h ^= (h << 13) | (h >>> 20);
      h += b.hashCode();
      h ^= (h << 23) | (h >>> 10);
      h += name().hashCode();
      return h;
    }
  
    @Override
    public boolean equals(Object o) {
      if (this.getClass() != o.getClass()) return false;
      DualFloatFunction other = (DualFloatFunction)o;
      return this.a.equals(other.a)
          && this.b.equals(other.b);
    }
  }
  