### Question:
WatchesReport { public Set<String> getPaths(long sessionId) { Set<String> s = id2paths.get(sessionId); return s != null ? Collections.unmodifiableSet(s) : null; } WatchesReport(Map<Long, Set<String>> id2paths); boolean hasPaths(long sessionId); Set<String> getPaths(long sessionId); Map<Long, Set<String>> toMap();  }### Answer:
@Test public void testGetPaths() { Set<String> s = r.getPaths(1L); assertEquals(2, s.size()); assertTrue(s.contains("path1a")); assertTrue(s.contains("path1b")); s = r.getPaths(2L); assertEquals(1, s.size()); assertTrue(s.contains("path2a")); assertNull(r.getPaths(3L)); }