JavaScript and JSP Web Development

In MVC web frameworks, input and business validations can be configured declaratively via XML mapping files (such as map.xml) or programmatically within the page handler class.

In PS (PeopleSoft) applications, page handlers are defined in the ps.xml configuration file, which is specific to the PS framework. web.xml is for general servlet configuration, map.xml is for field mappings, and tag libraries are for UI components - none of these define page handlers. The correct answer is C (ps.xml).

MetaDataAlias specifies which field name to extract from a metadata XML file. It's a configuration parameter that identifies the specific field to be used during metadata processing. This allows flexible mapping between XML structures and application data models.

Custom JSP tags are defined in tag libraries, which are XML files with a .tld (Tag Library Descriptor) extension. These tag library descriptors contain the tag definitions, including tag names, attributes, and handler classes. The tag library is then referenced in the JSP page or web.xml configuration.

To build a composite JSP page dynamically at runtime, the standard action tag <jsp:include> is used to merge the content of another resource into the current page.

A Metadata Alias defines the specific field name or identifier mapped from a metadata XML configuration file to be used by the application.

iBATIS (now MyBatis) is primarily a SQL Mapper that maps Java objects to SQL statements using XML or annotations. It's a JDBC framework (simplifies JDBC code) and is classified as an ORM-like tool, though it's a data mapper rather than a full ORM like Hibernate. It's not a complete J2EE framework (that would include Spring or Java EE).

JavaScript fully supports error handling using try...catch...finally blocks, making the statement that it does not provide this feature false.

In JavaScript, you can assign an event handler by setting the event property to an anonymous function or to a named function reference. Using += on event properties is invalid syntax in standard JavaScript.

The setTimeout function in JavaScript expects the delay time to be specified in milliseconds. Since 1 second equals 1000 milliseconds, a 4-second delay requires a value of 4000.

The standard DOM method to retrieve an HTML element by its ID attribute is document.getElementById(). This returns the element object if found, or null if no element with that ID exists. Options A, B, and D reference non-standard methods that don't exist in the DOM API.

In JavaScript, window.opener refers to the window that opened the current window. To change its URL, you assign a new value to window.opener.location. window.parent and window.top refer to iframe hierarchies.

The isNaN() function returns true if a value cannot be converted to a valid number. Using !isNaN(value) checks if the value IS numeric because isNaN first attempts to convert the value to a number. Options A and C reference non-existent functions, and option D has incorrect syntax (should be typeof, not type).