JAXB%20Interview%20Questions%20and%20Answers
Question: How to validate java objects?Answer: • The graph of Java objects can contain invalid data– could occur when objects created by unmarshalling are modified – could occur when objects are created from scratch • Use a Validator to validate the objects • Example Validator v = factory.createValidator(); try { v.validateRoot(cars); v.validate(car); } catch (ValidationException e) { // Handle the validation error described by e.getMessage(). } • Other Validator methods – boolean setEventHandler(ValidationEventHandler handler) • handleEvent method of ValidationEventHandler is called if validation errors are encountered • default handler terminates marshalling after first error • return true to continue validating • return false to terminate with ValidationException Pass an instance of javax.xml.bind.util.ValidationEventCollector (in jaxb-api.jar) to setEventHandler to collect validation errors and query them later instead of handling them during validation. ValidationEventCollector vec = new ValidationEventCollector(); v.setEventHandler(vec); v.validate(cars); ValidationEvent[] events = vec.getEvents(); |
Is it helpful?
Yes
No
Most helpful rated by users:
- What Is XML Binding?
- What is XML Binding Relationships?
- Please explain JAXB Use Cases.
- Why Use XML Binding?
- What are the goals of JAXB?