Comet / WebSocket Web Applications

Handling Http Request and Response in servlets and details about user authentication using mysql database

HTTP is the set of rules for transferring data across the World Wide Web. It uses clients like web browsers to make requests to servers using URLs over TCP/IP. HTTP defines request and response messages with request methods like GET and POST and response status codes. HTTP 1.1 supports persistent connections and caching via proxy servers for improved performance over HTTP 1.0.

This document provides an overview of HTTP including: - HTTP is a stateless protocol that does not require servers to retain user information across requests. - Popular HTTP proxy tools like Fiddler and Burp Suite can be used to inspect and debug HTTP traffic. - Key parts of HTTP include requests methods, response codes, headers for accepting content types, encoding, authentication, and more. - Common players that interact with HTTP include web servers, load balancers, caching servers, CDNs, and security tools.

This document discusses the Hypertext Transfer Protocol (HTTP) and how it enables communication on the World Wide Web. It begins by explaining some key concepts like URLs, web pages, and objects. It then describes how HTTP uses a client-server model where clients like web browsers make requests to servers, which respond with requested objects. The document outlines both non-persistent and persistent HTTP, how they establish TCP connections, and how persistent HTTP can improve performance. It also examines HTTP request and response messages, status codes, and how cookies can be used to maintain state across client-server interactions.

HTTP is an application-level protocol for distributed, collaborative hypermedia systems that has been used by the World Wide Web since 1990. The initial HTTP/0.9 version provided a simple protocol for raw data transfer, while HTTP/1.0 introduced MIME-like messages to include meta information and request/response modifiers. HTTP/1.0 did not sufficiently account for hierarchical proxies, caching, persistent connections or virtual hosts. HTTP sits at the top of the TCP/IP stack and uses ports to carry protocols between services, with HTTP typically using port 80. An HTTP message is delivered over a TCP/IP connection by chopping the message into chunks small enough to fit in TCP segments, which are then sent inside IP datagrams

The document discusses the format of HTTP messages, including requests and responses. An HTTP request contains a request line with the method, URL, and HTTP version. It also includes headers and an optional body. The response contains a status line with the HTTP version, status code, and reason phrase. It also includes headers and an optional body. The document provides examples of common request methods, status codes, and header types included in HTTP messages.

HTTP is a protocol for transmitting hypermedia documents across the internet. It uses a client-server model where a web browser makes HTTP requests to a web server. The server then responds with the requested resources. HTTP uses TCP/IP and the default port is 80. Requests have a method line specifying the request method (GET, POST, etc.), URL, and HTTP version. Responses have a status line with the HTTP version, status code, and reason phrase. Both include optional header lines and message body. Common methods are GET to retrieve a resource and POST to submit data to a server. Status codes indicate if a request was successful or encountered an error.

This document discusses HTML5 communication and messaging APIs, including cross-document messaging, CORS, server-sent events, and web sockets. Cross-document messaging allows sending messages between windows using postMessage. CORS enables cross-domain requests if responses include access control headers. Server-sent events allow push data from servers to clients. Web sockets provide bidirectional communications over a single TCP connection. The session explored examples of these APIs and their browser support.

This session focuses on how Java EE 7 provides extensive set of new and enhanced features to support standards like HTML5, WebSockets, and Server Sent Events among others.In this session we will show how these new features are designed and matched to work together for developing lightweight solutions matching end users high expectation from a web application’s responsiveness. The session will cover best practices and design patterns governing application development using JAX-RS 2.0, Async Servlet, and JSON-P (among others) as well as iterating over the pitfalls that should be avoided. During the session we will show code snippets and block diagrams that clarify use of APIs coming from the demo application we will show at the end.

HTTP is the application-layer protocol for transmitting hypertext documents across the internet. It works by establishing a TCP connection between an HTTP client, like a web browser, and an HTTP server. The client sends a request to the server using methods like GET or POST. The server responds with a status code and the requested resource. HTTP is stateless, meaning each request is independent and servers do not remember past client interactions. Cookies and caching are techniques used to maintain some state and improve performance.

1. The document discusses trends in web server architecture and technologies, including the evolution of servers like Apache and IIS to support scalability and extensibility through modularity. 2. It also covers web application development technologies and frameworks like JSP, ASP.NET, PHP, and how MGWSI provides normalized access to databases from different environments. 3. The document emphasizes that using a gateway like CSP or WebLink that handles requests as a proxy is better for performance and scalability than traditional web server architectures.

This document discusses WebSocket and Server-Sent Events (SSE) for building interactive web applications. It provides an overview of WebSocket including how it enables full-duplex communication over a single TCP connection and the handshake process. It also discusses the Java API for WebSocket including annotated endpoints and custom payloads. Finally, it covers SSE, the EventSource API, and an example SSE implementation in Java.

You want to collect the email id and a number of the potential customer. With the help of forms to help in building email lists, you will be to broadcasts the email to the contact with the personalization on a sequence Check out the blog to know How to build Email Lists by using HubSpot.

The HTTP protocol is an application-level protocol used for distributed, collaborative, hypermedia information systems. It operates as a request-response protocol between clients and servers, with clients making requests using methods like GET and POST and receiving responses with status codes. Requests and responses are composed of text-based headers and messages to communicate metadata and content. Caching and cookies can be used to improve performance and maintain state in this otherwise stateless protocol.

Lessons learned from migrating a large scale healthcare application from Windows to Unix at Partners Healthcare in Boston MA.

HTTP defines a client-server model for communication between browsers and web servers. A browser sends HTTP requests to a web server for web pages and objects. The server responds with HTTP responses containing the requested objects. HTTP uses TCP for reliable transmission and defines request and response message formats. Requests contain headers like Accept specifying object types. Responses contain status codes, headers like Content-Type, and the requested object data.

An overview of the HTTP protocol showing the protocol basics such as protocol versions, messages, headers, status codes, connection management, cookies and more. But it still remains an overview without in-depth information. Also some key aspects are left out (because of limited time) such as authentication, content negotiation, robots, web architecture etc..

This document provides an overview of real-time web technologies including Comet, long polling, HTTP streaming, forever frames, Server-Sent Events, and WebSockets. Comet is an umbrella term for techniques used to push data from a server to a browser in real-time. Long polling, HTTP streaming, and forever frames are different Comet programming models. Server-Sent Events and WebSockets are HTML5 solutions for real-time connections, with Server-Sent Events using HTTP streaming and WebSockets using a bidirectional TCP connection. Both approaches have advantages and disadvantages in terms of features, reliability, and proxy/firewall support.

Reverse Ajax, also known as Comet, allows a server to push data to a client without the client explicitly requesting it. This is achieved through techniques like long polling where the client opens a persistent connection to the server to receive messages as they happen. Common libraries that implement Reverse Ajax include CometD, Atmosphere, and DWR, with CometD being a preferred option as it supports websockets and offers full client/server functionality.

Comet is an umbrella term for web techniques that allow a web server to push data to a browser without an explicit request. Cometd is an open source project that implements the Bayeux protocol for asynchronous messaging and provides a framework for building comet applications with bidirectional communication. It uses techniques like long polling, streaming, and websockets to enable server push capabilities in web applications.

This document discusses servlets, which are Java programs that extend the capabilities of web servers to enable dynamic web content. Servlets run on the server-side and generate HTML responses to HTTP requests from clients. The document covers the basics of servlets, how they interface with web servers, their lifecycle including initialization and destruction, advantages over previous technologies like CGI, and implementation details.

This document discusses real-time web applications and the technologies needed to enable them. It describes how HTTP is half-duplex and led to hacks like long polling to simulate real-time behavior. The WebSocket protocol provides full-duplex communications by upgrading the HTTP handshake. This allows real-time messaging over a single connection. The document also covers asynchronous programming, event-driven architectures, and frameworks like Spring that support WebSockets and asynchronous APIs.

Ville Lautanala describes different transport channels that allow pushing data from servers to clients in real time. He also introduces a case study of Flowdock's experience with socket.io and WebSockets. Presentation from Frontend Finland meetup, March 14th. A slightly modified version was presented at SFJS, April 3rd.

This document discusses real-time web technologies including server-sent events (SSE), websockets, and polling. It provides an overview of each technology, including how they work, browser support, and server-side support. The document concludes with a demo of websockets in Windows 8 using ASP.NET and WCF and a request for questions and answers.