Java Servlets Mastery: Building Dynamic Web Applications

Discover how Java servlets act as the middle layer between web clients and databases, powering dynamic web applications and login workflows, with Eclipse and Tomcat setup.

Download and extract Apache Tomcat 7.0, configure it in Eclipse, start the server on port 8080, and run a dynamic web project with a welcome file list and index.html.

Explore the servlet lifecycle, from init to destroy, and learn how a web container maps URLs to servlets using annotations or Web.xml while creating a hello servlet.

Code a servlet and explore its lifecycle by overriding doGet or doPost, connect it to an HTML form via WebServlet annotation and action, and debug resource not available errors.

Discover how servlet mapping works by annotating hello servlet or configuring it in web.xml, route form actions to the servlet, and understand the web container’s lifecycle.

Explore do get versus do post in servlet life cycle: get puts parameters in the URL and can be bookmarked, while post encrypts and hides parameters in the request body.

Learn how servlet mapping routes requests through annotation and web.xml, define URL patterns, and validate a basic login app using get and post methods.

Build a very basic login servlet with hardcoded credentials using a username and password form, and validate admin/admin via request.getParameter in the doPost method.

learn how servlet config and servlet context initialize servlets using init parameters defined in web.xml. retrieve these values with config.getInitParameter, demonstrating per-servlet mappings and practical init examples.

Master servlet config and init parameters, access values with get init parameter, and understand that init runs once while service handles each request, with context enabling future database connections.

Access the one servlet context per web application and read init parameters via getInitParameter defined in web.xml, map new servlets, and verify outputs.

Understand how the load on startup element controls when a servlet is loaded and its init method runs, using a positive 0-128 value to order startup within the web container.

Discover how the MVC design pattern separates an application into model, view, and controller, with a servlet as controller and JSP views handling login validation.

Develop a simple mvc authentication app by wiring an html login form to a servlet controller, fetch username and password with request.getParameter, and validate via a model's checkLogin method.

Master the mvc design pattern with a login flow using authenticate user checks via servlet doPost, and the model validating credentials to yield login valid or invalid.

Examine content type and mime types, and master request dispatcher techniques to forward or include requests among servlets, html pages, and jsp pages within the mvc pattern.

Explain dispatching a request from servlet one to servlet two via a request dispatcher, forwarding username and password, and using include for partial responses with html and web.xml mappings.

Use the request dispatcher to forward an admin username login from servlet one to servlet two, and to include home.html for invalid usernames, staying on the current page.

Explore using response.sendRedirect in Java servlets to redirect to success or error pages, with relative or absolute URLs, and see why it can be easier than request dispatcher.

Compare request dispatcher forwards and send redirects, highlighting server-side versus client-side behavior, how they carry requests, and how dispatching accesses web content and web INF files.

Use a request dispatcher to forward requests to an HTML file inside web inf, enhancing security by preventing direct access, and contrast relative and absolute URLs with send redirect.

Create a simple servlet flow that uses an html username form to generate a cookie and pass it to another servlet, which prints the value via cookies.

Run a Java servlet web app on a server and configure the welcome file list. Explore cookie flow via cookie example and cookie value servlets, using do get and value.

Learn how hidden form fields enable session maintenance in Java servlets by sending hidden input values through forms and retrieving them with request.getParameter.

Learn how url rewriting appends session identifiers to the end of a URL using ? and & separated name=value pairs, and how to read them with request.getParameter in a servlet.

Master url rewriting to pass session data via name=value parameters in urls, learn how to construct query strings, and retrieve values with request.getParameter in servlets.

Explain how http session tracks a user across pages by creating a unique session id, setting and retrieving the username attribute, and sharing it between sender and receiver servlets.

Build a login flow with a login html page and a servlet, using post parameter retrieval, hardcoded admin authentication, cookies, and future oracle database integration.

Explore a basic login logout flow using cookies for session tracking in a Java servlets app, including handling post and get requests, creating and destroying cookies, and checking admin credentials.

Learn to implement login and logout using HttpSession in Java servlets by building a session-based authentication flow, handling user input, managing session attributes, and creating dedicated login and logout servlets.

Learn to log out a user by invalidating the HttpSession in a logout servlet, triggered via a post method from a logout button, completing the login/logout flow.

Learn how http sessions manage login and logout in Java servlets, retrieving attributes before invalidation and handling illegal state exceptions after the session is invalidated.

Learn how to move from hardcoded credentials to database driven login using Oracle DB, understand databases as organized collections of tables and records, and basic RDBMS concepts.

Explore relational database concepts with an Oracle database, using SQL to create, query, insert, update, delete, and manage tables, views, and permissions via an employee table example.

Learn to connect to an Oracle database via command line, create an employee table with id number, employee name varchar2(20), and employee city varchar2(20), understand varchar2 versus varchar memory usage.

Learn to insert records into the EMP table using value lists and column lists. Understand handling nulls and querying with select, where, and order by descending in Oracle SQL.

Master Oracle sql basics with select, insert, update, delete, where, and set on the emp table, noting case sensitivity and basic dml ddl dcl concepts.

Create and populate a login table in Oracle SQL, then query it using where, like wildcards, and distinct to retrieve and filter user data.

Explore accessing an Oracle database, using SQL to manipulate data, and distinguish DML from DDL with emphasis on commit versus auto commit through create table, insert, and select.

Explore Oracle database DDL and DML concepts, learn autocommit behavior, commit and rollback, and create, alter, drop, and rename tables while understanding normal versus abnormal exits.

Examine how alter and rename modify database objects, how drop removes tables, and how DDL, DCL, and TCL govern commits, savepoints, rollbacks, and privileges.

Explore using savepoints, rollback, and autocommit in Oracle to manage DML and DDL changes, illustrated by inserting, deleting, and selecting from a student table.

Explore Oracle database constraints, focusing on the not null rule and how null values affect inserts in a student table, plus unique, primary key, foreign key, check, and default.

learn how not null and unique constraints work in Oracle databases, preventing nulls and duplicate values while enforcing unique keys; practice inserting and counting rows to see constraints in action.

Primary key constraints combine not null and unique to give a unique identity to records in an employee table, using ID for fast lookups.

Explore Oracle database constraints on the employee table, including changing the primary key to a check, adding a salary column with a 500 default, and enforcing a check under 1000.

See how a Java application uses JDBC to connect to databases like Oracle, run queries such as select password from login, and enable login validation through a servlet-based flow.

Explore jdbc architecture by connecting java applications to databases via the driver manager and drivers for Oracle, MySQL, and PostgreSQL, creating connections, statements, and result sets using dsn in Eclipse.

Code a JDBC connection in a servlet project by loading the Oracle driver, establishing a DSN-based connection, and querying a login table with a statement and result set.

Iterate the JDBC result set with next, fetch username and password using get string by index or label, and validate login via a servlet with a database connection.

Execute a servlet-driven login flow that fetches the user password from the database via a db connection class, validates it in validate login class, and returns success or invalid password.

Demonstrates a login flow in a Java servlets app using jdbc, linking login.html to the login db servlet and validating credentials with a result set.

Explore servlet filters by building a login filter that handles pre-processing and post-processing, checks admin rights via a filter chain, and redirects users to admin or user pages.

Explain building a login flow with a login check servlet and login filter, validating admin access, forwarding requests through the filter chain, and handling redirects via web.xml mappings.

Learn how servlet filters perform pre-processing of requests before the login check servlet, using annotation or web.xml mapping, and enforce admin rights via a filter chain.

Develop a registration and login app using a database and jdbc, including creating a get connection method, a register user servlet, and an html form to insert and validate users.

Explore how to implement a register user servlet with a database connection, using prepared statements to insert username, password, and country into the users table, and verify registration with executeUpdate.

Learn to build a register and login workflow with servlets, using a db connection and prepared statements to verify credentials and enforce unique constraints in an mvc setup.