if (NotNullConstraint.NAME.equals(config.getConstraintName())) {
return new NotNullConstraint();
} else if (IntegerConstraint.NAME.equals(config.getConstraintName())) {
return new IntegerConstraint();
} else if (RangeConstraint.NAME.equals(config.getConstraintName())) {
return new RangeConstraint();
} else if (NotMatchesConstraint.NAME.equals(config.getConstraintName())) {
return new NotMatchesConstraint();
}else if (MatchesConstraint.NAME.equals(config.getConstraintName())) {
return new MatchesConstraint();
}else if (InvalidFieldConstraint.NAME.equals(config.getConstraintName())) {