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.builders.IAsterixListBuilder;
  import org.apache.asterix.builders.OrderedListBuilder;
  import org.apache.asterix.common.annotations.MissingNullInOutFunction;
  import org.apache.asterix.om.functions.BuiltinFunctions;
  import org.apache.asterix.om.functions.IFunctionDescriptorFactory;
  import org.apache.asterix.om.types.AOrderedListType;
  import org.apache.asterix.om.types.ATypeTag;
  import org.apache.asterix.om.types.AbstractCollectionType;
  import org.apache.asterix.om.types.BuiltinType;
  import org.apache.asterix.runtime.evaluators.base.AbstractScalarFunctionDynamicDescriptor;
  import org.apache.asterix.runtime.evaluators.functions.utils.RegExpMatcher;
  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.UTF8StringPointable;
  import org.apache.hyracks.data.std.util.GrowableArray;
  import org.apache.hyracks.data.std.util.UTF8StringBuilder;
  
  /**
   * This function takes 2 arguments, a string, and a pattern
   */
  @MissingNullInOutFunction
  public class StringRegExpMatchesDescriptor extends AbstractScalarFunctionDynamicDescriptor {
      private static final long serialVersionUID = 1L;
  
      public static final IFunctionDescriptorFactory FACTORY = StringRegExpMatchesDescriptor::new;
  
      @Override
      public IScalarEvaluatorFactory createEvaluatorFactory(final IScalarEvaluatorFactory[] args) {
          return new IScalarEvaluatorFactory() {
              private static final long serialVersionUID = 1L;
  
              @Override
              public IScalarEvaluator createScalarEvaluator(IEvaluatorContext ctx) throws HyracksDataException {
                  return new AbstractBinaryStringEval(ctx, args[0], args[1], getIdentifier(), sourceLoc) {
                      private final RegExpMatcher matcher = new RegExpMatcher();
  
                      private final UTF8StringBuilder stringBuilder = new UTF8StringBuilder();
                      private final GrowableArray stringBuilderArray = new GrowableArray();
  
                      private final IAsterixListBuilder listBuilder = new OrderedListBuilder();
                      private final AbstractCollectionType collectionType =
                              new AOrderedListType(BuiltinType.ASTRING, BuiltinType.ASTRING.getTypeName());
  
                      @Override
                      protected void process(UTF8StringPointable srcPtr, UTF8StringPointable patternPtr,
                              IPointable result) throws HyracksDataException {
                          matcher.build(srcPtr, patternPtr);
  
                          // Result is a list of type strings
                          listBuilder.reset(collectionType);
  
                          try {
                              // Add all the matches to the builder
                              while (matcher.find()) {
                                  String match = matcher.group();
                                  stringBuilderArray.reset();
  
                                  // Estimated length is number of characters + 1 (1 byte for string length)
                                  stringBuilder.reset(stringBuilderArray, match.length() + 1);
                                  stringBuilder.appendString(match);
                                  stringBuilder.finish();
  
                                  resultStorage.reset();
                                  dataOutput.writeByte(ATypeTag.SERIALIZED_STRING_TYPE_TAG);
                                  dataOutput.write(stringBuilderArray.getByteArray(), 0, stringBuilderArray.getLength());
                                  listBuilder.addItem(resultStorage);
                              }
  
                              resultStorage.reset();
                              listBuilder.write(dataOutput, true);
                              result.set(resultStorage);
                          } catch (IOException ex) {
                              throw HyracksDataException.create(ex);
                          }
                      }
                  };
              }
          };
      }
  
      @Override
      public FunctionIdentifier getIdentifier() {
          return BuiltinFunctions.STRING_REGEXP_MATCHES;
      }
  }
  