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.asterix.runtime.evaluators.functions;
  
  import java.io.IOException;
  
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.hyracks.algebricks.core.algebra.functions.FunctionIdentifier;
  import org.apache.hyracks.algebricks.runtime.base.IScalarEvaluatorFactory;
  import org.apache.hyracks.api.context.IEvaluatorContext;
  import org.apache.hyracks.api.exceptions.HyracksDataException;
  import org.apache.hyracks.api.exceptions.SourceLocation;
  import org.apache.hyracks.data.std.api.IPointable;
  import org.apache.hyracks.data.std.primitive.UTF8StringPointable;
  import org.apache.hyracks.data.std.util.GrowableArray;
  import org.apache.hyracks.data.std.util.UTF8StringBuilder;
  
  public abstract class AbstractBinaryStringStringEval extends AbstractBinaryStringEval {
  
      // For outputting results.
      protected final UTF8StringPointable resultStrPtr = new UTF8StringPointable();
      protected final GrowableArray resultArray = new GrowableArray();
      protected final UTF8StringBuilder resultBuilder = new UTF8StringBuilder();
  
      public AbstractBinaryStringStringEval(IEvaluatorContext context, IScalarEvaluatorFactory evalLeftFactory,
              IScalarEvaluatorFactory evalRightFactory, FunctionIdentifier funcID, SourceLocation sourceLoc)
              throws HyracksDataException {
          super(context, evalLeftFactory, evalRightFactory, funcID, sourceLoc);
      }
  
      @Override
      public void process(UTF8StringPointable leftPtr, UTF8StringPointable rightPtr, IPointable resultPointable)
              throws IOException {
          resultArray.reset();
          compute(leftPtr, rightPtr, resultStrPtr);
          writeResult(resultPointable);
      }
  
      /**
       * Computes a string value from two input strings.
       *
       * @param left
       *            , the first input argument.
       * @param right
       *            , the second input argument.
       * @param resultStrPtr
       *            , a pointable that is supposed to point to the result string.
       * @throws HyracksDataException
       */
      protected abstract void compute(UTF8StringPointable left, UTF8StringPointable right,
              UTF8StringPointable resultStrPtr) throws IOException;
  
      // Writes the result.
      private void writeResult(IPointable resultPointable) throws IOException {
          dataOutput.writeByte(ATypeTag.SERIALIZED_STRING_TYPE_TAG);
          dataOutput.write(resultStrPtr.getByteArray(), 0, resultStrPtr.getLength());
          resultPointable.set(resultStorage);
      }
  }
  