import org.apache.hadoop.mapred.gridmix.RandomTextDataGenerator; //导入依赖的package包/类
/**
 * Test if {@link RandomTextDataGenerator} can generate random words of 
 * desired size.
 */
@Test
public void testRandomTextDataGenerator() {
  RandomTextDataGenerator rtdg = new RandomTextDataGenerator(10, 0L, 5);
  List<String> words = rtdg.getRandomWords();

  // check the size
  assertEquals("List size mismatch", 10, words.size());

  // check the words
  Set<String> wordsSet = new HashSet<String>(words);
  assertEquals("List size mismatch due to duplicates", 10, wordsSet.size());

  // check the word lengths
  for (String word : wordsSet) {
    assertEquals("Word size mismatch", 5, word.length());
  }
}
 

import org.apache.hadoop.mapred.gridmix.RandomTextDataGenerator; //导入依赖的package包/类
/**
 * Test if {@link RandomTextDataGenerator} can generate same words given the
 * same list-size, word-length and seed.
 */
@Test
public void testRandomTextDataGeneratorRepeatability() {
  RandomTextDataGenerator rtdg1 = new RandomTextDataGenerator(10, 0L, 5);
  List<String> words1 = rtdg1.getRandomWords();

  RandomTextDataGenerator rtdg2 = new RandomTextDataGenerator(10, 0L, 5);
  List<String> words2 = rtdg2.getRandomWords();
  
  assertTrue("List mismatch", words1.equals(words2));
}
 

import org.apache.hadoop.mapred.gridmix.RandomTextDataGenerator; //导入依赖的package包/类
/**
 * Test if {@link RandomTextDataGenerator} can generate different words given 
 * different seeds.
 */
@Test
public void testRandomTextDataGeneratorUniqueness() {
  RandomTextDataGenerator rtdg1 = new RandomTextDataGenerator(10, 1L, 5);
  Set<String> words1 = new HashSet(rtdg1.getRandomWords());

  RandomTextDataGenerator rtdg2 = new RandomTextDataGenerator(10, 0L, 5);
  Set<String> words2 = new HashSet(rtdg2.getRandomWords());
  
  assertFalse("List size mismatch across lists", words1.equals(words2));
}