a's body...

Footer

Consider the following JSP for b.jsp :


Header

b's body...

Footer

In many cases, the developers obtain the code from the UI group and literally convert it into a JSP as necessary. As shown above, each JSP has a duplicate header and footer. Solution 1 is undesirable because changes in common view components, like header and footer, require changes in all relevant pages, as each page is responsible for laying out the view components. This simple solution lacks foresight. With so much HTML and JSP code duplication, we minimize the number of pages but at a heavy maintenance cost. There is strong coupling between the different view components, which, as I explained earlier, is undesirable.
Solution 2: JSP include
Consider the following JSP for a.jsp :


<%-- include header --%>

a's body...

<%-- include footer --%>



Consider the following JSP for b.jsp :


<%-- include header --%>

b's body...

<%-- include footer --%>



Note that common view components, like header and footer, are split up using the JSP include mechanism.
Consider this header.jsp :
Header

Consider this footer.jsp :
Footer

Solution 2 nicely addresses some of Solution 1's major shortcomings. You only need to change common view components once. Hence, this solution greatly eliminates HTML and JSP code repetition, significantly improving application maintainability. It increases the page number a bit, but drastically reduces the tight coupling between common view components and other pages. On the complexity scale, this solution is simple and readily implemented on many real-world applications. However, it has one major drawback: if you change how and where you organize the view components (i.e., by changing the component layout), then you would need to update every page -- resulting in an expensive and prohibitive change. Solution 2 achieves view component reuse, but does not achieve the reuse of layout and templating logic.
Solution 3: Tiles insert
Consider this JSP for a.jsp :
<%@ taglib uri="/WEB-INF/tiles.tld" prefix="tiles" %>


<%-- include header --%>

a's body...

<%-- include footer --%>



Consider this JSP for b.jsp :
<%@ taglib uri="/WEB-INF/tiles.tld" prefix="tiles" %>


<%-- include header --%>

b's body...

<%-- include footer --%>



Instead of using the JSP include mechanism, Solution 3 uses the Tiles insert mechanism. Using the Tiles insert tag, you include the view components in the appropriate positions. In all other aspects, the solution mirrors the JSP include solution (Solution 2) exactly, with the same advantages and disadvantages.
Solution 4: Splitting bodies
Consider this a.jsp :
<%@ taglib uri="/WEB-INF/tiles.tld" prefix="tiles" %>


<%-- include header --%>

<%-- include body --%>

<%-- include footer --%>



Consider this b.jsp :
<%@ taglib uri="/WEB-INF/tiles.tld" prefix="tiles" %>


<%-- include header --%>

<%-- include body --%>

<%-- include footer --%>



Solution 4 differs slightly from the Tiles insert solution. Solution 4 separates the core bodies into their individual pages, like aBody.jsp and bBody.jsp .
Consider the following JSP for aBody.jsp :
a's body...

Consider the following JSP for bBody.jsp :
b's body...