, if its structure meets the XML specification, i.e., it is syntactically correct.A well-formed XML document exhibits a tree-like structure, and can be processed by an XML processor.It is a formal description of the structure of an XML document, i.e., which elements are allowed, which elements must be present, which elements are optional, the sequence and relationship of the elements.Document Type Definition (DTD) is used to define the structure of an XML document. Schema Factory; public class Unmarshal Demo The validation performed during the unmarshal raised 3 events. Schema Factory; public class Marshal Demo The validation performed during the marshal raised 3 events.
Returning false from the handle Event method will cause the JAXB operation to stop, returning true will allow it to continue (if possible).package validation; import LOCATOR LINE NUMBER: 3 COLUMN NUMBER: 25 OFFSET: -1 OBJECT: null NODE: null URL: null EVENT SEVERITY: 1 MESSAGE: cvc-type.3.1.3: The value 'Jane Doe' of element 'name' is not valid. SAXParse Exception: cvc-type.3.1.3: The value 'Jane Doe' of element 'name' is not valid. SAXParse Exception: cvc-complex-type.2.4.d: Invalid content was found starting with element 'customer'. LOCATOR LINE NUMBER: 7 COLUMN NUMBER: 12 OFFSET: -1 OBJECT: null NODE: null URL: null package validation; import LOCATOR LINE NUMBER: -1 COLUMN NUMBER: -1 OFFSET: -1 OBJECT: validation.A DTD can be declared inside an XML document (i.e., if it meets the constraints spelled out in a DTD (Document Type Definition) or an XML Schema, imposed by a specific application.DTD defines the structure of a certain type of XML documents, which could facilitate exchanging of documents between computer systems electronically.It also helps in standardizing a certain class of documents.XML focus on the content of the document and gives no clue on the appearance or presentation.