Assert

public class Assert {

    public static final void assertTrue (final String errorMessage,
           boolean assertee){
        if (!assertee) {
            throw new RuntimeException(errorMessage);
        }
    }

    public static final void assertEquals (final String errorMessage,
            final String expressionOne, final String expressionTwo) {
        if (!expressionOne.equals(expressionTwo)) {
            throw new RuntimeException(errorMessage);
        }
    }

    public static void assertEquals(String errorMessage,
           int expressionOne, int expressionTwo) {
        if (expressionOne != expressionTwo) {
            throw new RuntimeException(errorMessage);
        }
    }

    public static void assertNull(String errorMessage, String assertee) {
        if (assertee != null) {
             throw new RuntimeException(errorMessage);
        }
    }

    public static void assertNotNull(String errorMessage,
            String assertee) {
        if (assertee == null) {
             throw new RuntimeException(errorMessage);
        }
    }
}