### Question:
RangeUtil { public static int checkLessThan(int n, int expected, String name) { if (n >= expected) { throw new IllegalArgumentException(name + ": " + n + " (expected: < " + expected + ')'); } return n; }  static long checkPositive(long n, String name); static int checkPositiveOrZero(int n, String name); static int checkLessThan(int n, int expected, String name); static int checkLessThanOrEqual(int n, long expected, String name); static int checkGreaterThanOrEqual(int n, int expected, String name);  }### Answer:
@Test(expected = IllegalArgumentException.class) public void checkLessThanMustFailIfArgumentIsGreaterThanExpected() { RangeUtil.checkLessThan(1, 0, "var"); }
@Test(expected = IllegalArgumentException.class) public void checkLessThanMustFailIfArgumentIsEqualToExpected() { final int n = 1; final int actual = RangeUtil.checkLessThan(1, 1, "var"); assertThat(actual, is(equalTo(n))); }
@Test public void checkLessThanMustPassIfArgumentIsLessThanExpected() { final int n = 0; final int actual = RangeUtil.checkLessThan(n, 1, "var"); assertThat(actual, is(equalTo(n))); }