try {
Expression exp;
Vector v = new Vector();
v.add(new StringConstant(s1));
exp = new ContainsOnlyLetters(v,true);
assertTrue(exp.evaluate().equals(Boolean.TRUE));
v.clear();
v.add(propertySensor1);
exp = new ContainsOnlyLetters(v,true);
assertTrue(exp.evaluate().equals(Boolean.TRUE));
v.clear();
v.add(new StringConstant(s2));
exp = new ContainsOnlyLetters(v,true);
assertTrue(exp.evaluate().equals(Boolean.FALSE));
v.clear();
v.add(propertySensor2);
exp = new ContainsOnlyLetters(v,true);
assertTrue(exp.evaluate().equals(Boolean.FALSE));
v.clear();
v.add(new StringConstant(s3));
exp = new ContainsOnlyLetters(v,true);
assertTrue(exp.evaluate().equals(Boolean.FALSE));
v.clear();
v.add(propertySensor3);
exp = new ContainsOnlyLetters(v,true);
assertTrue(exp.evaluate().equals(Boolean.FALSE));
v.clear();
v.add(new StringConstant(s4));
exp = new ContainsOnlyDigits(v,true);