@Test
public void printVC() throws Exception {

    ByteArrayOutputStream outContent = new ByteArrayOutputStream();
    System.setOut(new PrintStream(outContent));
    testClock.set("Proc1", 2);
    testClock.set("Proc3", 3);
    testClock.set("Proc2", 7);
    testClock.printVC();
    assertEquals("{\"Proc1\":2, \"Proc2\":7," +
            " \"Proc3\":3}\n", outContent.toString());
    System.setOut(null);
}