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 org.apache.asterix.om.functions.BuiltinFunctions;
  import org.apache.asterix.om.functions.IFunctionDescriptorFactory;
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.asterix.runtime.evaluators.base.AbstractScalarFunctionDynamicDescriptor;
  import org.apache.asterix.runtime.exceptions.UnsupportedTypeException;
  import org.apache.hyracks.algebricks.core.algebra.functions.FunctionIdentifier;
  import org.apache.hyracks.algebricks.runtime.base.IScalarEvaluator;
  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.data.std.api.IPointable;
  import org.apache.hyracks.data.std.primitive.VoidPointable;
  import org.apache.hyracks.dataflow.common.data.accessors.IFrameTupleReference;
  
  /**
   * This runtime function checks if the input is null.
   * If the input is not null, just return it directly;
   * Otherwise, throw a runtime exception.
   */
  public class CheckUnknownDescriptor extends AbstractScalarFunctionDynamicDescriptor {
  
      private static final long serialVersionUID = 1L;
      public static final IFunctionDescriptorFactory FACTORY = CheckUnknownDescriptor::new;
  
      @Override
      public IScalarEvaluatorFactory createEvaluatorFactory(final IScalarEvaluatorFactory[] args) {
          return new IScalarEvaluatorFactory() {
              private static final long serialVersionUID = 1L;
  
              @Override
              public IScalarEvaluator createScalarEvaluator(final IEvaluatorContext ctx) throws HyracksDataException {
                  return new IScalarEvaluator() {
                      private IPointable inputArg = new VoidPointable();
                      private IScalarEvaluator eval = args[0].createScalarEvaluator(ctx);
  
                      @Override
                      public void evaluate(IFrameTupleReference tuple, IPointable result) throws HyracksDataException {
                          eval.evaluate(tuple, inputArg);
                          byte[] data = inputArg.getByteArray();
                          int offset = inputArg.getStartOffset();
  
                          if (data[offset] == ATypeTag.SERIALIZED_MISSING_TYPE_TAG
                                  || data[offset] == ATypeTag.SERIALIZED_NULL_TYPE_TAG) {
                              throw new UnsupportedTypeException(sourceLoc, getIdentifier(), data[offset]);
                          }
                          result.set(inputArg);
                      }
                  };
              }
          };
      }
  
      @Override
      public FunctionIdentifier getIdentifier() {
          return BuiltinFunctions.CHECK_UNKNOWN;
      }
  
  }
  