Webcommerce Computer Networks Webcommerce by Linnea Reppa Douglas Martindale Lev Shalevich

Part I

Web Client (HTML) HTTP Request HTTP Response Java Servlet JSP Pages Java Beans CGI Script The E-Boutique Commerce Site: Three tier architecture using Java Server technologies

Java Server Technologies Java Servlets JavaServer Pages JavaBeans Need a Web server that supports the Java Servlet and JavaServer Pages APIs. The E-Boutique site uses the Apache Tomcat server (available at Run over standard HTTP

Java Servlet Technology Servlets are standard, server-side Java application components that act as a middle layer between Web clients and enterprise applications and/or databases. Purpose is to accept an HTTP request, perform any necessary processing, which may involve invoking other applications and/or objects, and format an HTML reply. All processing occurs in the server. Analogous to Common Gateway Interface (CGI) programs, but provide superior scalability, portability, and convenience.

Java Servlet Technology (Continue) With traditional CGI, the operating system creates a new process for every HTTP request. A Servlet gets loaded into the Web server's memory the first time it is requested, and subsequent requests call the servlet instance already in memory with threads dispatched to handle individual requests. Because the compiled servlet is stored in memory, fewer system resources are needed at run-time and system response is very fast. Servlets come with an infrastructure for automatically parsing HTML form data, reading and setting HTTP headers, and tracking sessions.

Java Servlet Technology (Continue) The HttpServletRequest object automatically created by the Servlet represents a session object. The session object can be used to store any type of object, including beans, and is identified by a unique session key. This feature allows for the persistence of data throughout the session. The HttpServletRequest also contains the form data of the most recently submitted HTTP form. The servlet engine takes care of all form field parsing.

Java Server Pages (JSP) JSP technology was developed as a method to separate dynamic content, specific to the processing of a user request, from static HTML page design. JSP pages mix HTML and JSP-specific syntax. JSP pages are composed of HTML written in the normal manner, and Java code enclosed in special tags for the dynamic content. A JSP page is in fact a servlet: JSP class files extend the HttpJspBase class, which in turn implements the Servlet interface.

Java Server Pages (JSP) (Continue) The advantage of this architecture is that there is very little processing logic within the presentation page itself; it is simply responsible for retrieving the JavaBean objects previously created by the servlet controller, extracting the bean information for dynamic content, and inserting the content within standard HTML components. Like servlets, provide a very efficient solution because they're only loaded once as an operating system process and individual requests are handled via threads.

JavaBeans JavaBeans provide an architecture for building and using Java components. JavaBean components are nothing but Java classes that follow a well-defined design/naming pattern. A bean encapsulates its properties by declaring them private and provides public access (get/set) methods for reading and modifying their values. Persistence, a key feature of JavaBeans, enables a bean to save its state. The use of JavaBeans with Servlet and JSP technology is especially advantageous because beans can act as data encapsulators to allow data to persist, enabling collaboration between servlets JSP pages.

Part II

Results of WebStress on E-boutique's OrderProc Servlet (before server maintenance)

Median Response Time Related to Simultaneous Users (Order Processing Servlet before Server Maintenance)

Mean Response Time Related to Simultaneous Users (Order Processing Servlet before Server Maintenance

Median Response Time Related to Simultaneous Users (Order Processing Servlet before Server Maintenance)- Filtered Responses

Mean Response Time Related to Simultaneous Users (Order Processing Servlet before Server Maintenance)- Filtered Responses

Error Rates for Order Processing Servlet Before Server Maintenance

Comparison of Median Responses vs. Filtered Median Response (Order Processing Servlet before Server Maintenance)

Comparison of Mean Responses vs. Filtered Mean Responses (Order Processing Servlet before Server Maintenance)

Results of WebStress on E-boutique's OrderProc Servlet (after server maintenance)

Median Response Time Related to Simultaneous Users (Order Processing Servlet after Server Maintenance)

Mean Response Time Related to Simultaneous Users (Order Processing Servlet after Server Maintenance)

Median Response Time Related to Simultaneous Users (Order Processing Servlet after Server Maintenance)- Filtered Responses

Mean Response Time Related to Simultaneous Users (Order Processing Script after Server Maintenance)- Filtered Errors

Error Rates for Order Processing Servlet after Server Maintenance

Comparison of Median Responses vs. Filtered Median Responses (Order Processing Servlet after Server Maintenance)

Comparision of Mean Responses vs. Filtered Mean Responses (Order Processing Script after Server Maintenance)

Results of WebStress on E-boutique's HTML (before server maintenance)

Median Response Time Related to Simultaneous Users (E-Boutique HTML before Server Maintenance)

Mean Response Time Related to Simultaneous Users (E- Boutique HTML before Server Maintenance)

Median Response Time Related to Simultaneous Users (E-Boutique HTML before Server Maintenance)- Filtered Responses

Mean Response Time Related to Simultaneous Users (E-Boutique HTML before Server Maintenance)- Filtered Responses

Error Rates of E-Boutique HTML before Server Maintenance

Comparison of Median Responses vs. Filtered Median Responses (E-Boutique HTML before Server Maintenance)

Comparison of Mean Responses vs. Filtered Mean Responses (E-Boutique HTML before Server Maintenance)

Results of WebStress on E-boutique's home page (after server maintenance)

Median Response Time Related to Simultaneous Users (E-Boutique HTML after Server Maintenance)

Mean Response Time Related to Simultaneous Users (E- Boutique HTML after Server Maintenance)

Median Response Time Related to Simultaneous Users (E-Boutique HTML after Server Maintenance)- Filtered Responses

Mean Response Time Related to Simultaneous Users (E- Boutique HTML after Server Maintenance)-Filtered Responses

Error Rates for E-Boutique HTML after Server Maintenance

Comparison of Median Responses vs. Filtered Median Responses (E-Boutique HTML after Server Maintenance)

Comparison of Mean Responses vs. Filtered Median Responses (E-Boutique HTML after Server Maintenance)

Results of WebStress on E-boutique's Streaming Media (RealServer)

Median Response Time Related to Simultaneous Users (RealServer Streaming Media)

Mean Response Time Related to Simultaneous Users (RealServer Streaming Media)

Mean Response Time vs. Median Response Time - RealServer Streaming Media

Various Graphs

Comparison of Median of All Results With Server Maintenance (Order Processing Servlet)

Comparison of all Mean Responses Regarding Server Maintenance (Order Processing Servlet)

Comparison of Median Results With Server Maintenance (Order Processing Servlet) - Filtered Responses

Comparison of Mean Results With Server Maintenance (Order Processing Servlet) - Filtered Responses

Comparison of Median of All Results With Server Maintenance (E-Boutique HTML)

Comparison of Mean of All Results With Server Maintenance (E-Boutique HTML)

Comparison of Median Results With Server Maintenance (E-Boutique HTML) - Filtered Responses

Comparison of Mean Results With Server Maintenance (E-Boutique HTML) - Filtered Responses

Comparison of Error Rates for the Order Processing Servlet Regarding Server Maintenance

Comparison of Error Rates for E-Boutique HTML Regarding Server Maintenance

Comparison of Best Error Rates in Each Test (Servlet, HTML, Streaming Media)

Comparison of Best Median Response Times in Each Test

Comparison of Best Mean Response Times in Each Test

Comparison of Best Median Response Times in Each Test (Filtered Responses)

Comparison of Best Mean Response Times in Each Test (Filtered Responses)