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.fuzzyjoin.similarity;
  
  import static org.apache.hyracks.data.std.primitive.UTF8StringPointable.generateUTF8Pointable;
  import static org.junit.Assert.assertEquals;
  
  import org.apache.hyracks.data.std.primitive.UTF8StringPointable;
  import org.junit.Test;
  
  public class SimilarityMetricEditDistanceTest {
  
      private static final SimilarityMetricEditDistance ed = new SimilarityMetricEditDistance();
  
      @Test
      public void test() throws Exception {
          // For this case, the edit-distance of two strings is 3.
          UTF8StringPointable leftStrPointable1 = generateUTF8Pointable("coupon not available in store");
          UTF8StringPointable rightStrPointable1 = generateUTF8Pointable("coupon is available in store");
  
          // The edit-distance between leftStrPointable1 and the following is 14.
          UTF8StringPointable rightStrPointable2 = generateUTF8Pointable("coupon in store");
  
          byte[] leftBytes1 = leftStrPointable1.getByteArray();
          int leftStartOffset1 = leftStrPointable1.getStartOffset();
          byte[] rightBytes1 = rightStrPointable1.getByteArray();
          int rightStartOffset1 = rightStrPointable1.getStartOffset();
          byte[] rightBytes2 = rightStrPointable2.getByteArray();
          int rightStartOffset2 = rightStrPointable2.getStartOffset();
  
          // Case 1 - normal - no early termination
          int edThresh = 3;
          int edVal = ed.UTF8StringEditDistance(leftBytes1, leftStartOffset1, rightBytes1, rightStartOffset1, edThresh);
          assertEquals(edThresh, edVal);
  
          // Case 2 - the length difference between two strings is greater than edThresh.
          // Even without calculating the distance, the method should return -1.
          edVal = ed.UTF8StringEditDistance(leftBytes1, leftStartOffset1, rightBytes2, rightStartOffset2, edThresh);
          assertEquals(SimilarityMetricEditDistance.SIMILARITY_THRESHOLD_NOT_SATISFIED_VALUE, edVal);
  
          // Case 3 - the edit distance is 14, but the threshold is 1.
          // The early termination should happen and the returned value should be -1.
          edThresh = 1;
          edVal = ed.UTF8StringEditDistance(leftBytes1, leftStartOffset1, rightBytes2, rightStartOffset2, edThresh);
          assertEquals(SimilarityMetricEditDistance.SIMILARITY_THRESHOLD_NOT_SATISFIED_VALUE, edVal);
  
          // Case 4 - the edit distance is 14, but the threshold is 13.
          // The early termination will not happen. But, the resulting edit distance is greater than the given threshold.
          // So, the final returned value should be -1.
          edThresh = 13;
          edVal = ed.UTF8StringEditDistance(leftBytes1, leftStartOffset1, rightBytes2, rightStartOffset2, edThresh);
          assertEquals(SimilarityMetricEditDistance.SIMILARITY_THRESHOLD_NOT_SATISFIED_VALUE, edVal);
      }
  
  }
  