spark-gpu-master/mllib/src/test/java/org/apache/spark/mllib/fpm/JavaPrefixSpanSuite.java
/*
 * 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.
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package org.apache.spark.mllib.fpm;

import java.util.Arrays;
import java.util.List;

import org.junit.After;
import org.junit.Assert;
import org.junit.Before;
import org.junit.Test;

import org.apache.spark.api.java.JavaRDD;
import org.apache.spark.api.java.JavaSparkContext;
import org.apache.spark.mllib.fpm.PrefixSpan.FreqSequence;

public class JavaPrefixSpanSuite {
  private transient JavaSparkContext sc;

  @Before
  public void setUp() {
    sc = new JavaSparkContext("local", "JavaPrefixSpan");
  }

  @After
  public void tearDown() {
    sc.stop();
    sc = null;
  }

  @Test
  public void runPrefixSpan() {
    JavaRDD<List<List<Integer>>> sequences = sc.parallelize(Arrays.asList(
      Arrays.asList(Arrays.asList(1, 2), Arrays.asList(3)),
      Arrays.asList(Arrays.asList(1), Arrays.asList(3, 2), Arrays.asList(1, 2)),
      Arrays.asList(Arrays.asList(1, 2), Arrays.asList(5)),
      Arrays.asList(Arrays.asList(6))
    ), 2);
    PrefixSpan prefixSpan = new PrefixSpan()
      .setMinSupport(0.5)
      .setMaxPatternLength(5);
    PrefixSpanModel<Integer> model = prefixSpan.run(sequences);
    JavaRDD<FreqSequence<Integer>> freqSeqs = model.freqSequences().toJavaRDD();
    List<FreqSequence<Integer>> localFreqSeqs = freqSeqs.collect();
    Assert.assertEquals(5, localFreqSeqs.size());
    // Check that each frequent sequence could be materialized.
    for (PrefixSpan.FreqSequence<Integer> freqSeq: localFreqSeqs) {
      List<List<Integer>> seq = freqSeq.javaSequence();
      long freq = freqSeq.freq();
    }
  }
}
