src/main/java/org/fest/assertions/LongAssert.java
public @NotNull LongAssert isLessThan(long other) {
    if (actual < other) {
      return this;
    }
    failIfCustomMessageIsSet();
    throw failure(unexpectedGreaterThanOrEqualTo(actual, other));
  }
public @NotNull LongAssert isLessThan(long other) {
    if (actual < other) {
      return this;
    }
    failIfCustomMessageIsSet();
    throw failure(unexpectedGreaterThanOrEqualTo(actual, other));
  }
Verifies that the actual {@code Long} is less than the given one.

@param other the given value.
@return this assertion object.
@throws AssertionError if the actual {@code Long} is not less than the given one.