3.18. Message Data Validation

When processing an order message, you should perform a number of validations. First, check that the supplied username follows a format of an upper case character, followed by five digits (for example, S12345 or G54321). To perform this validation, you should use regular expression.

Next, check that the supplied e-mail address is in a valid format. Use a regular expression to check it.

Confirm that each order item's productId field follows a format of exactly three digits (such as 123). Use a regular expression to do this.

Finally, you need to confirm that the total for each order item does not exceed 50.00 (price * quantity is not greater than 50.00). Perform this validation using an MVEL expression.