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CSCI 6962: Server-side Design and Programming. Course Introduction and Overview. Topics. Introduction to Client-Server Web Architectures Java Server Faces and Active Server Pages Problems and Topics in Server-side Programming Programming Assignments. Client-Server Web Architecture. - PowerPoint PPT Presentation
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CSCI 6962: Server-side Design and Programming
Course Introduction and Overview
Topics• Introduction to Client-Server Web Architectures• Java Server Faces and Active Server Pages• Problems and Topics in Server-side Programming• Programming Assignments
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Client-Server Web Architecture• Client browser sends request for page to server
– May contain form data and other information
• Server sends response page and sends to client• May need to generate response page dynamically
– Form parameters– Previous requests (such as items purchased so far)– Information in database
Focus of this course
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Client-Server Web Architecture
ClientBrowserwww.csis.ysu.edu/~john/Syllabus.html
Request to www.csis.ysu.edu for Syllabus.html
Server
john public_html
port
Response containing Syllabus.htm as a long string (<html><head><title>CSCI 6962 Syllabus</title> </head><body>…)
Syllabus.html
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Dynamic Form Handling• Form data appended to request string
Generates the request:http://www.cis.ysu.edu/~john/cgi-bin/test.pl&quantity=3
<FORM NAME="purchaseform" METHOD=GET ACTION=http://www.csis.ysu.edu/~john/cgi-bin/test.pl >
Quantity: <INPUT TYPE="text" NAME="quantity" /><BR /><BR />
<INPUT TYPE="submit" VALUE="SUBMIT">
/FORM>
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Form HandlingServer must:
– Listen on port for requests– Parse request to determine values of parameters– Dynamically generate appropriate response page based on
parameter values– Send response page back to client
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Web Containers• Program running continuously on server• Runs code to handle requests• Built-in methods for parsing requests, generating
responses• Handles other important functions:
– Session tracking– Database access– Email generation– Security and encryption– …
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Web Containers
Client
Browser
Server
Port
http://homer.cis.ysu.edu/reciept.jsp&quantity=3
Web Container
Constantly running in background
Listen on portExecute code in requested server pageGenerate corresponding html page
<HTML><HEAD><TITLE>cgi-bin response</TITLE></HEAD><BODY><P>Thank you for your order of <%= request.getParameter(“quantity”) %>widgets!</P></BODY></HTML>
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Web Containers• Glassfish
– Written in Java – Built on Apache Tomcat– NetBeans IDE– Acts as engine for Java servlets, Java Server Pages and Java
Server Faces
• Microsoft Internet Information Server (IIS)– Visual Basic/C#– Acts as engine for Active Server Pages
Server-side Evolution• Servlets
– Programmatically generating response page
• Server pages– Inserting dynamically generated code into web page– Goal: separate web design and dynamic code
• Server faces/Active server pages– Directly linking client-side form elements to server-side
objects (JavaBeans)– Goal: separate web page development from underlying
business logic 10
Java Servlets
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Get quantity from request
Create output to response
Write response page as string to output with quantity inserted
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Java Server Pages
Java code executed inside web page
Resulting value inserted into html
Java Server Faces• Use managed beans to control information
– Data storage between pages– Computation methods (total bill, taxes, etc.)– Validation methods (positive quantity, items available)– Long-term storage (database read/write of orders)
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JSF web page JSF managed bean
Web design team Business logic team
Java Server Faces
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Bean stores quantity
Getters and setters to allow access
Java Server Faces
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XML tags specific to JSF
Input bound to quantity property of bean
Java Server Faces
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widgetBean
quantity: 33
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Active Server Pages• Active Server Page approach:
Create “form” which is translated to html
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Active Server Pages• Server-side code manipulates “form elements”
– Subroutine called when page submitted– Data read from elements (actually request string)– Used to set value of other elements
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Active Server Pages• Resulting form translated to response page
Why Two Platforms• Both widely used in practice
– Other platforms (Springs, Ruby, etc.) based on JSF model• Different approaches but common ideas
– Same underlying representation– Same best practices for web site design
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Other Major Topics• Session management• Modular web site design• Validation and error handling• Database manipulation• AJAX client-server communication• Security
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Session Handling• Most web transactions are sessions consisting of
series of requests and responses• Must associate steps if multiple clients
Who submitted this request?
Modular Web Pages• Most pages on same
site have similar content,layout, etc.
• Goal: Write once, include in all pages
• Tools:– Facelets (Java)– Master Pages (ASP)
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Form Validation
• Detecting user error– Built-in validation tools
• Correcting user error– Providing information or how to correct error
• Preventing user error– Field types/values – Error tolerance
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Database Manipulation• Database driver provides access to databases• Built-in tools to manipulate/display data
– JDBC: classes to query/manipulate database– Java Persistence API beans– ASP Data Source objects
web container
JPA bean
JSFpage database
database driverJDBC DBMS
database server
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AJAX• Asynchronous JavaScript and XML • Based on JavaScript running in browser
– JavaScript code sends data to server, reads response– Response is simple data instead of entire page – JavaScript code then modifies page without re-rendering it completely
Method call
Web Page
Server
Return valueJavaScript
Web Site Security
• SSL/TLS for encryption• Certificates for server authentication• Secure programming against attacks
– SQL injection– Cross-site scripting
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Request Server
Response
Client
Certificate
database
database server
Programming Assignments• Introductory Assignments
– Simple Java Server Faces web site– Simple Active Server Pages web site
• Web Site Project (four parts)– Modular user interface design– Validation and error handling– Database access– Shopping cart and other support objects
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Web Site Project• “E-Commerce” site of your design• You choose platform (JSF or ASP)
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List of products
List of productsList of
productsList of products
IndividualProduct
pages with “add” option
“Cart” of added
products
Shipping/payment/
etc. information
\Database of products and orders
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Background Knowledge• Java or C++ (for JSP)
– May want to get Java reference– I will cover basics in class
• Visual Basic or C# (for ASP)– Basics covered in class– If more familiar with C# can get corresponding text
• Basic html (including forms and tables)• Basic SQL
