54.What are the different types of JSF events?

There are three types of JSF events namely Action Events: Action events are the events that are generated for the ui components like command button or command hyperlink. Value Change Events: Value change events refers to the UI components textfield, radio button, list box etc. The value change event will get fired as soon as the value is changed in the UI component. Phase Events: This type of event involves the events to be fired in one of the six phases of JSF lifecycle either during start or towards the end of each phase.

55.What is a listener class?

A class which is associated with an event is called a listener class. For example, if the event is a valueChange event then the corresponding listener class ValueChangeListener is associated with it. Read more at JSF Listeners Example to learn more about these listeners.

56.What is the significance of facelets tag?

JSF provides a special set of tags that gives the flexibility to manage common tags/parts in one place for more than one application. These tags allow us to create a common layout that can be used across applications. You can include facelets tags using below code;

57.What are some of the facelets tags?

ome of the important facelets tags are; tag tag tag tag tag tag

58.What are the different types of validations in JSF?

There are two types of validations namely; 1. Declarative Validations: The validations that are fired using JSF standard validators or Bean validators fall under declarative type. 2. Imperative validation: The standard validation messages would not be sufficient in all the cases and sometimes may require complex validations that are declared by the user overriding the standard validations and these are called Imperative validations.

59.What are different types of expressions supported by JSF EL?

JSF Expression Language supports following types of expressions. Immediate value expressions Deferred value expressions Value expression and method expression

60.What are immediate and deferred value expressions?

Immediate expressions are evaluated and results are rendered as soon as the page is displayed initially. The syntax for immediate evaluation is ${}. Deferred expressions are evaluated during the lifecycle phase whenever it is requested by the user. The syntax for deferred evaluation is #{expression}.

61.Explain value expression and method expressions?

Value expressions usually fetch a value or set a value. These expressions can be further categorized into rvalue and lvalue expressions. value expressions can both read and write data whereas rvalue expressions can only read data. A method expression allows user to invoke a public method of the bean that returns the result necessary for validating the data component and handling events.