@Test
public void testUnJar() throws Exception {

  File unjarDir = new File(TEST_ROOT_DIR, "unjar-all");
  assertFalse("unjar dir shouldn't exist at test start",
              new File(unjarDir, "foobar.txt").exists());
  // Unjar everything
  RunJar.unJar(new File(TEST_ROOT_DIR, TEST_JAR_NAME),
               unjarDir);
  assertTrue("foobar unpacked",
             new File(unjarDir, "foobar.txt").exists());
  assertTrue("foobaz unpacked",
             new File(unjarDir, "foobaz.txt").exists());
}