### Question:
Etl { Map<String, Integer> transform(Map<Integer, List<String>> old) { throw new UnsupportedOperationException("Delete this statement and write your own implementation."); }    }### Answer:
@Test public void testTransformOneValue() { Map<Integer, List<String>> old = new HashMap<Integer, List<String>>() { { put(1, Arrays.asList("A")); } }; old = Collections.unmodifiableMap(old); Map<String, Integer> expected = new HashMap<String, Integer>() { { put("a", 1); } }; expected = Collections.unmodifiableMap(expected); assertEquals(expected, etl.transform(old)); }
@Ignore("Remove to run test") @Test public void testTransformMoreValues() { Map<Integer, List<String>> old = new HashMap<Integer, List<String>>() { { put(1, Arrays.asList("A", "E", "I", "O", "U")); } }; old = Collections.unmodifiableMap(old); Map<String, Integer> expected = new HashMap<String, Integer>() { { put("a", 1); put("e", 1); put("i", 1); put("o", 1); put("u", 1); } }; expected = Collections.unmodifiableMap(expected); assertEquals(expected, etl.transform(old)); }
@Ignore("Remove to run test") @Test public void testMoreKeys() { Map<Integer, List<String>> old = new HashMap<Integer, List<String>>() { { put(1, Arrays.asList("A", "E")); put(2, Arrays.asList("D", "G")); } }; old = Collections.unmodifiableMap(old); Map<String, Integer> expected = new HashMap<String, Integer>() { { put("a", 1); put("e", 1); put("d", 2); put("g", 2); } }; expected = Collections.unmodifiableMap(expected); assertEquals(expected, etl.transform(old)); }
@Ignore("Remove to run test") @Test public void testFullDataset() { Map<Integer, List<String>> old = new HashMap<Integer, List<String>>() { { put(1, Arrays.asList("A", "E", "I", "O", "U", "L", "N", "R", "S", "T")); put(2, Arrays.asList("D", "G")); put(3, Arrays.asList("B", "C", "M", "P")); put(4, Arrays.asList("F", "H", "V", "W", "Y")); put(5, Arrays.asList("K")); put(8, Arrays.asList("J", "X")); put(10, Arrays.asList("Q", "Z")); } }; old = Collections.unmodifiableMap(old); Map<String, Integer> expected = new HashMap<String, Integer>() { { put("a", 1); put("b", 3); put("c", 3); put("d", 2); put("e", 1); put("f", 4); put("g", 2); put("h", 4); put("i", 1); put("j", 8); put("k", 5); put("l", 1); put("m", 3); put("n", 1); put("o", 1); put("p", 3); put("q", 10); put("r", 1); put("s", 1); put("t", 1); put("u", 1); put("v", 4); put("w", 4); put("x", 8); put("y", 4); put("z", 10); } }; expected = Collections.unmodifiableMap(expected); assertEquals(expected, etl.transform(old)); }