struts interview questions

Ques: 37 How will you use the Tile layout in your struts application?

Ans: To use a Tile, You need to perform the following steps:

  * Import the Tiles taglib with the taglib directive.

  * Use tiles:insert tag to insert the Tile layout into the current page.

  * Use tile:put tag to pass string parameters.

  * Use tiles:put tag to pass parameter Tiles.

Ques: 38 How will you create the the JSP Tile definition?

Ans: Definitions specify default parameters for Tile layouts. You can create definitions in JSP or XML. To create a JSP Tile Definition, follow the following steps:

  * Import the Tiles tag library using the taglib directive.

  * Ensure that the definition is created only once using the logic:notPresent tag.

  *  Define the definition with the tiles:definition tag and pass the JSP that defines the Tile layout and the scope of the newly created definition.

  * Define the default parameters with the tiles:put tag.

Ques: 39 How will you use the the JSP Tile definition in your struts application?

Ans: To use a Tile definition, follow these steps:

  * Import the Tiles taglib with taglib directive.

  * Include the JSP page that creates the definition by using jsp:include.

  * Use the tiles:insert tag, but specify the definition bean name and scope instead of the Tile layout page.

  * Use the tiles:put attribute to specify the title and content but not header and footer parameters.

Ques: 40 Describe the scope of the Tile in the Struts application?

Ans: The Tiles framework defines an additional scope called Tile scope. Like page scope, Tile scope is more private than request scope. It allows the user of the Tile to pass arguments (called parameters) to the TIle. Like a display function, it makes the page callable.

Nested tiles do not share the same Tile scope as their parent. The Tile scope of the current Tile is saved before the nested Tile is displayed; after the nested Tile finishes, the parent's Tile scope is restored to the request.

Ques: 41 What is the difference between the jsp:include tag and tiles:insert tag?

Ans: The jsp:include tag allows you to call a page and pass it to request parameters (jsp:param); the tiles:insert tag is similar but more powerful. The tiles:insert allows you to call a page and pass it sub-pages (called Tiles) and attributes. Tile scope lets you pass variables that are available only to that Tile layout.

Ans:

Code Repetition is reduced

Use of Tiles reduce the code repetition to a great extent. Code repetition is bad but repetition of layout logic could be worst. Tiles also handle this issue. As you have layout templates based on which all the pages are combined, you don't need to repeat the code for layout. Other view components are also reusable and can be used in the same application at other places reducing the code repetition.

2. Low coupling between pages

Coupling is the degree of interactivity between two entities. It is always suggested to minimize coupling between unrelated classes, packages, and so on. Same principle is applied to view components. Tiles reduce the coupling between unrelated view components.

3. High layout control

Tiles provide great layout control by providing layout templates.

4. I18N support for locale-specific loading

5. Dynamic Page building

Pages are built dynamically in tiles. You can control the page view by configuring it through xml.

6. Elimination of duplicate and redundant information

Tiles eliminate the duplicate and redundant information in the configuration file by providing Tiles inheritance.

7. Central location for view components

Tiles save definition of all the components at one place (in tilesDef.xml) and hence can be modified easily when required.