In many cases, Encoding has the potential to defuse attacks that rely on lack of input validation.For example, if you use HTML entity encoding on user input before it is sent to a browser, it will prevent most XSS attacks.
To contrive an example, consider an XML data set that keeps track of personnel data. All sections should be reviewed The most common web application security weakness is the failure to properly validate input from the client or environment.Data from the client should never be trusted for the client has every possibility to tamper with the data.(You will see how to deal with multiple namespaces in the next section.) You can also specify the schema file in the application, which is the case for Here, too, there are mechanisms at your disposal that will let you specify multiple schemas. Namespaces let you combine elements that serve different purposes in the same document without having to worry about overlapping names.Note - The material discussed in this section also applies to validating when using the SAX parser.