Vibrant Technologies is headquarted in Mumbai,India.We are the best Advanced java training provider in Navi Mumbai who provides Live Projects to students.We provide Corporate Training also.We are Best Advanced Java classes in Mumbai according to our students and corporators
This document provides an overview and summary of Apache 2.2 configuration including:
1) Apache release statuses and where development is focused;
2) Common configuration directives like Listen, DocumentRoot, and VirtualHosts;
3) Tips for modularizing configuration using Include directives and separating into files.
Ch 22: Web Hosting and Internet Serverswebhostingguy
Web hosting involves providing space on a server for websites. Linux is commonly used for hosting due to its maintainability and performance. A web server software like Apache is installed to handle HTTP requests from browsers. URLs identify resources on the web using protocols like HTTP and FTP. CGI scripts allow dynamic content generation but pose security risks. Load balancing distributes server load across multiple systems. Choosing a server depends on factors like robustness, performance, updates, and cost. Apache is widely used and configurable using configuration files that control server parameters, resources, and access restrictions. Virtual interfaces allow a single server to host multiple websites. Caching and proxies can improve performance and security. Anonymous FTP allows public file downloads.
An introduction to the Docker concept. Experiences with ASP.NET Core and Docker, How Docker can help produce modular deployments for ASP.NET web applications. Presented at Vermont Code Camp #8, UVM, Burlington VT, September 17, 2016
Nginx is an open-source, lightweight web server that can serve static files, act as a reverse proxy, load balancer, and HTTP cache. It is fast, scalable, and improves performance and security for large websites. Some key companies that use Nginx include Google, IBM, LinkedIn, and Facebook. Nginx follows a master-slave architecture with an event-driven, asynchronous, and non-blocking model. The master process manages worker processes that handle requests in a single-threaded manner, improving concurrency.
Basic Understanding and Implement of Node.jsGary Yeh
Node.js is an event-driven JavaScript runtime built on Chrome's V8 engine. It uses non-blocking I/O and an event loop to handle multiple connections simultaneously without blocking. The document discusses Node.js' event loop model and asynchronous I/O, how callbacks allow non-blocking operations, and how modules and frameworks like Express allow building scalable network applications.
The document summarizes Apache Manager, a directory-based tool for managing Apache web servers. It stores Apache configuration directives in a hierarchy of objects in a directory service. This allows common directives to be consolidated and inherited by multiple servers. The Apache Manager includes a configuration daemon that extracts directives from the directory and builds httpd.conf files, and a web interface for managing configurations across servers from a single location. Storing configurations in a directory provides advantages like platform independence, centralized management, and reduced duplication.
This document compares AFNetworking and NSURLSession for making network requests in iOS, and describes how to implement caching. AFNetworking makes common networking tasks easier by providing convenient methods, while NSURLSession is Apple's preferred networking API introduced in iOS 7. It also supports features like background transfers and pause/resume of requests. Caching can be implemented using NSURLCache, which stores responses locally to improve performance and offline usage.
A short introduction (with many examples) to the Scala programming language and also an introduction to using the Play! Framework for modern, safe, efffcient and reactive web applications.
This document provides an overview and summary of Apache 2.2 configuration including:
1) Apache release statuses and where development is focused;
2) Common configuration directives like Listen, DocumentRoot, and VirtualHosts;
3) Tips for modularizing configuration using Include directives and separating into files.
Ch 22: Web Hosting and Internet Serverswebhostingguy
Web hosting involves providing space on a server for websites. Linux is commonly used for hosting due to its maintainability and performance. A web server software like Apache is installed to handle HTTP requests from browsers. URLs identify resources on the web using protocols like HTTP and FTP. CGI scripts allow dynamic content generation but pose security risks. Load balancing distributes server load across multiple systems. Choosing a server depends on factors like robustness, performance, updates, and cost. Apache is widely used and configurable using configuration files that control server parameters, resources, and access restrictions. Virtual interfaces allow a single server to host multiple websites. Caching and proxies can improve performance and security. Anonymous FTP allows public file downloads.
An introduction to the Docker concept. Experiences with ASP.NET Core and Docker, How Docker can help produce modular deployments for ASP.NET web applications. Presented at Vermont Code Camp #8, UVM, Burlington VT, September 17, 2016
Nginx is an open-source, lightweight web server that can serve static files, act as a reverse proxy, load balancer, and HTTP cache. It is fast, scalable, and improves performance and security for large websites. Some key companies that use Nginx include Google, IBM, LinkedIn, and Facebook. Nginx follows a master-slave architecture with an event-driven, asynchronous, and non-blocking model. The master process manages worker processes that handle requests in a single-threaded manner, improving concurrency.
Basic Understanding and Implement of Node.jsGary Yeh
Node.js is an event-driven JavaScript runtime built on Chrome's V8 engine. It uses non-blocking I/O and an event loop to handle multiple connections simultaneously without blocking. The document discusses Node.js' event loop model and asynchronous I/O, how callbacks allow non-blocking operations, and how modules and frameworks like Express allow building scalable network applications.
The document summarizes Apache Manager, a directory-based tool for managing Apache web servers. It stores Apache configuration directives in a hierarchy of objects in a directory service. This allows common directives to be consolidated and inherited by multiple servers. The Apache Manager includes a configuration daemon that extracts directives from the directory and builds httpd.conf files, and a web interface for managing configurations across servers from a single location. Storing configurations in a directory provides advantages like platform independence, centralized management, and reduced duplication.
This document compares AFNetworking and NSURLSession for making network requests in iOS, and describes how to implement caching. AFNetworking makes common networking tasks easier by providing convenient methods, while NSURLSession is Apple's preferred networking API introduced in iOS 7. It also supports features like background transfers and pause/resume of requests. Caching can be implemented using NSURLCache, which stores responses locally to improve performance and offline usage.
A short introduction (with many examples) to the Scala programming language and also an introduction to using the Play! Framework for modern, safe, efffcient and reactive web applications.
Modern application frameworks like Spring promote a POJO-based programming model, and POJOs are inherently easy to unit test. But how can we effectively integration test our application outside the container while still getting as close to a production-like environment as possible? This session will show attendees how to approximate a target production environment using the Spring TestContext Framework to drive fast, repeatable, "out-of-container" integration tests. To simulate a live system, the session will cover open source integration testing techniques such as the use of in-memory databases, JMS providers, and Servlet containers as well as mock SMTP and FTP servers.
Как мы взломали распределенные системы конфигурационного управленияPositive Hack Days
В лекции речь пойдет о том, как команда исследователей обнаружила и эксплуатировала уязвимости различных систем конфигурационного управления в ходе пентестов. Авторы представят различные инструменты распределенного управления конфигурациями, например Apache ZooKeeper, HashiCorp Consul и Serf, CoreOS Etcd; расскажут о способах создания отпечатков этих систем, а также о том, как использовать в своих целях типичные ошибки в конфигурации для увеличения площади атак.
ASIT is one of the leading providers of Programming courses "Advanced JAVA",along with professional certification. We associate with industry experts to deliver the training requirements of Job seeks and working professionals.for more details please visit our website.
The document discusses different approaches to networking on iOS, including lower-level frameworks like CFNetwork and higher-level frameworks in the Foundation like NSURLConnection. It focuses on NSURLConnection, describing how it uses NSURLRequest to define requests and NSURLResponse to handle responses. NSURLConnection can be used synchronously or asynchronously with delegates or blocks to retrieve URL content.
We are excited to continue our work on BeanStalk with the introduction of a range of great new features. If you are a Python shop you'll learn how BeanStalk now supports Python containers and the Django and Flask frameworks. Hear about BeanStalk integration with RDS and how custom configuration of containers is possible through simple configuration files.
Tomcat New Evolution discusses the new features introduced in Tomcat 6 and 7. Some key highlights include:
- Tomcat 6 introduced features like memory leak prevention, CSRF protection, session fixation protection, NIO connector, Comet support, logging improvements, web services support, and clustering.
- Tomcat 7 features included externalizing static resources, WebSocket support, easier embedded usage, and asynchronous logging.
- Both versions aimed to improve performance, security, and scalability through these new capabilities. Tomcat continues evolving to support newer standards and address common issues.
The document discusses using Play Framework, Docker, CircleCI, and AWS together to create an automated microservices build pipeline. Key aspects include using GitHub for source control, CircleCI for continuous integration to build Docker images, pushing images to Docker Hub, and deploying to AWS using ECS for container orchestration. The author demonstrates setting up each part of the pipeline live.
The document is an Apache web server tutorial for Linux that describes how to install and configure Apache, mod_ssl, and PHP on a Linux server. It discusses installing Apache and additional modules using yum, configuring Apache to start on boot with chkconfig, editing httpd.conf to set server settings and enable virtual hosts, creating a website directory structure, and starting the Apache service. The tutorial provides guidance for setting up the basic components needed to host a dynamic website on Apache.
This along with the binaries to be found at my github profiles @ github.com/shahenshah99 is used to present and conduct a hands-on session on securely deploying containers in docker at the time of production
PowerUp - Automating Windows Privilege EscalationWill Schroeder
This slidedeck was given as a firetalk at @BSidesBoston '14, and covers the genesis and implementation of PowerUp, a Powershell tool for Windows privilege escalation.
CON 2107- Think Async: Embrace and Get Addicted to the Asynchronicity of EEMasoud Kalali
This presentation covers the whole spectrum of Asynchronous processing present in Java EE through introducing a use case. The coverage starts with introducing the usecase and showing how a mix of JMS, MDB and Async Servlet can address the requirement of the use case. The session will also cover asynchronicity in JAX-RS as well as covering NIO in Servlet 3.1
This 3-day course provides an overview of installing, configuring, and administering the Apache Web Server on Linux. It covers topics such as installing and configuring Apache, adding security, supporting dynamic and virtual hosting, using proxies and firewalls, and monitoring and improving performance. Participants should have prior Linux system administration experience. Upon completing the course, students will be able to install, configure, secure and manage all aspects of the Apache Web Server.
This document discusses OWIN (Open Web Interface for .NET), which defines a standard interface between .NET web servers and web applications to decouple them. It aims to make .NET web development resemble HTTP, be asynchronous and composable. OWIN defines an "AppFunc" that takes an environment dictionary as input and returns a task. This allows multiple middleware components to process requests and responses in a pipeline. The document outlines the goals of OWIN and provides an overview of its key concepts like applications, middleware, hosts and the environment.
The document discusses Node.js, including what it is, its benefits, use cases, and readiness for enterprise use. Node.js is an event-driven, non-blocking I/O model that is well-suited for building scalable web applications with real-time features but not CPU-intensive batch processes. It promotes fast development with smaller codebases and is widely adopted by enterprises. The document also covers Node.js application architecture, database support, development tools, deployment practices, and strategies for adoption.
This document discusses various Docker orchestration platforms and their key features. It begins with questions about when an orchestration platform is needed and how to choose one. It then covers considerations like deployment scenarios, features for scheduling, networking, service discovery, recovery, and auto-scaling. The rest of the document demonstrates Docker Swarm, Docker EE, Mesosphere DC/OS, AWS ECS, and Kubernetes/GCP and how they handle scheduling, load balancing, self-healing, auto-scaling and more.
Vibrant Technologies is headquarted in Mumbai,India.We are the best Advanced java training provider in Navi Mumbai who provides Live Projects to students.We provide Corporate Training also.We are Best Advanced Java classes in Mumbai according to our students and corporators
This document outlines goals, realities, and options for increasing awareness of ATL (Approaches to Learning) at a school. The goal is to disseminate information about ATL and involve the administration and entire school community. However, the reality is that only a small number of people are currently aware of ATL. Several options for training teachers, support staff, and administrators are proposed, and monitoring implementation through professional development days and assessing success will help reach the goal of schoolwide ATL awareness.
The Nepse index decreased throughout last week, losing 27.59 points (-2.39%) to close at 1134.47 due to political instability and the ongoing fuel crisis. Technical indicators such as MACD, RSI, and OBV pointed to a bearish market sentiment. Support and resistance levels were seen at 1112 and 1183 respectively. Volatility is expected to remain high given domestic economic challenges.
Modern application frameworks like Spring promote a POJO-based programming model, and POJOs are inherently easy to unit test. But how can we effectively integration test our application outside the container while still getting as close to a production-like environment as possible? This session will show attendees how to approximate a target production environment using the Spring TestContext Framework to drive fast, repeatable, "out-of-container" integration tests. To simulate a live system, the session will cover open source integration testing techniques such as the use of in-memory databases, JMS providers, and Servlet containers as well as mock SMTP and FTP servers.
Как мы взломали распределенные системы конфигурационного управленияPositive Hack Days
В лекции речь пойдет о том, как команда исследователей обнаружила и эксплуатировала уязвимости различных систем конфигурационного управления в ходе пентестов. Авторы представят различные инструменты распределенного управления конфигурациями, например Apache ZooKeeper, HashiCorp Consul и Serf, CoreOS Etcd; расскажут о способах создания отпечатков этих систем, а также о том, как использовать в своих целях типичные ошибки в конфигурации для увеличения площади атак.
ASIT is one of the leading providers of Programming courses "Advanced JAVA",along with professional certification. We associate with industry experts to deliver the training requirements of Job seeks and working professionals.for more details please visit our website.
The document discusses different approaches to networking on iOS, including lower-level frameworks like CFNetwork and higher-level frameworks in the Foundation like NSURLConnection. It focuses on NSURLConnection, describing how it uses NSURLRequest to define requests and NSURLResponse to handle responses. NSURLConnection can be used synchronously or asynchronously with delegates or blocks to retrieve URL content.
We are excited to continue our work on BeanStalk with the introduction of a range of great new features. If you are a Python shop you'll learn how BeanStalk now supports Python containers and the Django and Flask frameworks. Hear about BeanStalk integration with RDS and how custom configuration of containers is possible through simple configuration files.
Tomcat New Evolution discusses the new features introduced in Tomcat 6 and 7. Some key highlights include:
- Tomcat 6 introduced features like memory leak prevention, CSRF protection, session fixation protection, NIO connector, Comet support, logging improvements, web services support, and clustering.
- Tomcat 7 features included externalizing static resources, WebSocket support, easier embedded usage, and asynchronous logging.
- Both versions aimed to improve performance, security, and scalability through these new capabilities. Tomcat continues evolving to support newer standards and address common issues.
The document discusses using Play Framework, Docker, CircleCI, and AWS together to create an automated microservices build pipeline. Key aspects include using GitHub for source control, CircleCI for continuous integration to build Docker images, pushing images to Docker Hub, and deploying to AWS using ECS for container orchestration. The author demonstrates setting up each part of the pipeline live.
The document is an Apache web server tutorial for Linux that describes how to install and configure Apache, mod_ssl, and PHP on a Linux server. It discusses installing Apache and additional modules using yum, configuring Apache to start on boot with chkconfig, editing httpd.conf to set server settings and enable virtual hosts, creating a website directory structure, and starting the Apache service. The tutorial provides guidance for setting up the basic components needed to host a dynamic website on Apache.
This along with the binaries to be found at my github profiles @ github.com/shahenshah99 is used to present and conduct a hands-on session on securely deploying containers in docker at the time of production
PowerUp - Automating Windows Privilege EscalationWill Schroeder
This slidedeck was given as a firetalk at @BSidesBoston '14, and covers the genesis and implementation of PowerUp, a Powershell tool for Windows privilege escalation.
CON 2107- Think Async: Embrace and Get Addicted to the Asynchronicity of EEMasoud Kalali
This presentation covers the whole spectrum of Asynchronous processing present in Java EE through introducing a use case. The coverage starts with introducing the usecase and showing how a mix of JMS, MDB and Async Servlet can address the requirement of the use case. The session will also cover asynchronicity in JAX-RS as well as covering NIO in Servlet 3.1
This 3-day course provides an overview of installing, configuring, and administering the Apache Web Server on Linux. It covers topics such as installing and configuring Apache, adding security, supporting dynamic and virtual hosting, using proxies and firewalls, and monitoring and improving performance. Participants should have prior Linux system administration experience. Upon completing the course, students will be able to install, configure, secure and manage all aspects of the Apache Web Server.
This document discusses OWIN (Open Web Interface for .NET), which defines a standard interface between .NET web servers and web applications to decouple them. It aims to make .NET web development resemble HTTP, be asynchronous and composable. OWIN defines an "AppFunc" that takes an environment dictionary as input and returns a task. This allows multiple middleware components to process requests and responses in a pipeline. The document outlines the goals of OWIN and provides an overview of its key concepts like applications, middleware, hosts and the environment.
The document discusses Node.js, including what it is, its benefits, use cases, and readiness for enterprise use. Node.js is an event-driven, non-blocking I/O model that is well-suited for building scalable web applications with real-time features but not CPU-intensive batch processes. It promotes fast development with smaller codebases and is widely adopted by enterprises. The document also covers Node.js application architecture, database support, development tools, deployment practices, and strategies for adoption.
This document discusses various Docker orchestration platforms and their key features. It begins with questions about when an orchestration platform is needed and how to choose one. It then covers considerations like deployment scenarios, features for scheduling, networking, service discovery, recovery, and auto-scaling. The rest of the document demonstrates Docker Swarm, Docker EE, Mesosphere DC/OS, AWS ECS, and Kubernetes/GCP and how they handle scheduling, load balancing, self-healing, auto-scaling and more.
Vibrant Technologies is headquarted in Mumbai,India.We are the best Advanced java training provider in Navi Mumbai who provides Live Projects to students.We provide Corporate Training also.We are Best Advanced Java classes in Mumbai according to our students and corporators
This document outlines goals, realities, and options for increasing awareness of ATL (Approaches to Learning) at a school. The goal is to disseminate information about ATL and involve the administration and entire school community. However, the reality is that only a small number of people are currently aware of ATL. Several options for training teachers, support staff, and administrators are proposed, and monitoring implementation through professional development days and assessing success will help reach the goal of schoolwide ATL awareness.
The Nepse index decreased throughout last week, losing 27.59 points (-2.39%) to close at 1134.47 due to political instability and the ongoing fuel crisis. Technical indicators such as MACD, RSI, and OBV pointed to a bearish market sentiment. Support and resistance levels were seen at 1112 and 1183 respectively. Volatility is expected to remain high given domestic economic challenges.
This document provides information about Anna Kochetkova and her content marketing business called Content Queen. Anna is a Russian-born Australian who has been storytelling since childhood. She has degrees in journalism, communications, and business. Anna arrived in Australia in 2008 and has been working in marketing since. Content Queen provides content marketing services like blogging, copywriting, and storytelling for entrepreneurs and business owners. The business helps clients improve their marketing through engaging content.
Choco-libertin is a chocolate company started by four friends who were interested in chocolate. They lacked chocolate making experience but had financial backing. The company collaborated with a Scottish chocolate company and focused on innovation. Their vision is to make people happy by serving good quality and healthy chocolates based on customer feedback. They support charitable causes and introduced calorie-free chocolates to attract customers and shareholders.
The search for_extraterrestrial_civilizations_with_large_energy_suppliesSérgio Sacani
This document discusses potential signatures that could distinguish transiting megastructures from exoplanets. It identifies nine potential anomalous signatures:
1) Non-disk shapes could produce anomalous transit light curves.
2) Non-gravitational forces could cause orbits inconsistent with the star's density.
3) "Swarms" of many structures could cause irregular or aperiodic transit signals.
4) Structures large enough to completely occult the star could be detected.
5) Very low inferred masses would be anomalous for objects blocking significant starlight.
6) Nearly achromatic eclipses would differ from exoplanets' atmosphere-influenced transits.
This document provides an overview of the Android operating system, including its history, architecture, versions, features, advantages, and disadvantages. Android was founded in 2003 and was later acquired by Google in 2005. It uses an open source Linux kernel and is developed by the Open Handset Alliance. The architecture consists of four layers - the Linux kernel, native libraries, the Android runtime (Dalvik virtual machine), and applications. Key features include multi-tasking, a rich application ecosystem, and integration with Google services. Advantages are customization and openness, while disadvantages include inconsistent designs between apps and battery drain issues on some devices.
My Node.js workshop from Sela's Developer Conference 2015.
In the Workshop we covered The basics Node.js api's and the express web application framework.
The document is a presentation about Node.js, a JavaScript runtime built on Chrome's V8 JavaScript engine. It discusses how Node.js uses an event-driven, non-blocking I/O model that makes it particularly suited for real-time web applications and I/O-intensive applications compared to traditional threaded server models. It provides examples of Node.js features like asynchronous I/O, event loops, modules and the npm package manager.
Save 10% off ANY FITC event with discount code 'slideshare'
See our upcoming events at www.fitc.ca
Node.js: The What, The How and The When
with Richard Nieuwenhuis
Node.js is a JavaScript runtime built on Chrome's V8 engine that is used to develop fast and scalable network applications. It uses an event-driven, non-blocking I/O model that makes it lightweight and efficient, especially for data-intensive real-time applications that run across distributed devices. Node.js relies heavily on asynchronous event handling, callbacks, and data streams.
1. The document discusses an FTP servlet, which acts as an intermediate application between FTP clients and servers. It helps distribute computing load from the FTP server to the servlet.
2. An FTP servlet wraps FTP traffic over HTTP or HTTPS for firewall friendliness and enhanced security. It processes client requests by overriding the service() method.
3. Using a generic servlet for FTP would make the servlet protocol independent. However, existing servlet containers do not support the FTP protocol at the connector level needed to implement this. The document explores using other protocols like WebDAV and SOAP with servlets as well.
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 provides an overview of servlets, including:
1. Servlets are Java programs that extend the functionality of web servers by dynamically processing HTTP requests and responses.
2. The life cycle of a servlet involves loading, instantiating, processing requests, and destroying.
3. Common steps to create and run a simple "Hello World" servlet using Tomcat include writing Java code, compiling, configuring deployment descriptors, and making HTTP requests.
4. Servlets offer benefits over other technologies like CGI scripts by being more efficient, persistent, portable, robust, and secure.
This document discusses the tools and components needed to develop a Node.js application. It explains that Node.js, NPM, and an IDE or text editor are required. A Node.js application consists of importing modules, creating a server to listen for requests, and reading and responding to requests. Code samples are provided to demonstrate creating a basic "Hello World" Node.js application that runs on port 8080 when loaded on the command line. The document also discusses callbacks and blocking vs non-blocking behavior in Node.js.
A server is a computer program that provides services to other programs. The computer running the server program is called the server. Servers are often categorized by their purpose, such as web servers, application servers, proxy servers, and mail servers. A web server responds to HTTP requests to deliver web content and services. Servlets are Java programs that extend server functionality and respond dynamically to requests. Servlets provide advantages over older CGI programs like improved performance and scalability.
This document discusses asynchronous I/O in Java and Scala using the Play Framework. It describes how LinkedIn uses a service-oriented architecture with hundreds of services making requests to each other. It then covers how Play supports non-blocking I/O using asynchronous code, promises, and futures to allow parallel requests without blocking threads. Key points covered include using map and flatMap to transform promises and futures, handling errors and timeouts, and the benefits of non-blocking I/O for scalability.
The document discusses Java servlets and Java Server Pages (JSP). It provides an introduction to HTTP and web interactions, and describes how servlets and JSPs allow Java code to generate dynamic web content. It explains the request-response cycle between clients and servers, and how servlets fit into this model. It also covers servlet containers, the servlet lifecycle, deployment descriptors, and developing and running servlets.
The document provides an overview of the Java programming language and related technologies including servlets, JSP, Struts, Hibernate, and Tiles. It discusses what Java is, its history and technology, the different Java editions, J2EE and its components, how servlets and JSP work, database handling with JDBC, the MVC pattern implemented by Struts, and object relational mapping with Hibernate. Tiles is described as a framework for assembling web pages from individual visual components.
This power point presentation provides an overview of advance Java topics including servlets, session handling, database handling, JSP, Struts, MVC, and Hibernate. It begins with a brief introduction of Java and its history. It then discusses advance Java topics like J2EE, servlets, session handling using different techniques. It also covers database handling using JDBC and topics like JSP, Struts framework, MVC pattern, Tiles framework, and Hibernate for object-relational mapping.
Slides from my workshop about node.js which I conducted in Girl Geek Dinner Bangalore. More details at http://sudarmuthu.com/blog/introduction-to-node-js-at-yahoo-girl-geek-dinner
This document provides an introduction to Java servlet technology. It discusses how servlets address limitations of CGI scripts by providing a portable way to generate dynamic web content from the server side using Java. Key topics covered include the servlet interface, lifecycle, and advantages over CGI such as improved performance and portability. Configuration and use of servlets within Eclipse and Tomcat are also explained.
The document discusses servlet technology and how it is used to create dynamic web applications. Some key points:
- Servlet technology allows creating web applications that reside on the server-side and generate dynamic web pages.
- Servlets are more robust and scalable than previous CGI technology due to being implemented in Java.
- The servlet API defines interfaces like Servlet, GenericServlet, HttpServlet, ServletRequest, and ServletResponse that are used to build servlets.
Java servlets are small Java programs that run on a web server and respond to requests from a client browser. Servlets receive HTTP requests from the browser, generate dynamic content, and return HTTP responses. When the server first loads a servlet, it calls the servlet's init() method to initialize it. The servlet then handles requests via its service() method, building responses using server resources. When the server removes a servlet, it calls the servlet's destroy() method to perform cleanup. Servlets allow dynamic web content and interaction between clients and server resources like databases.
The document provides an overview of middleware in Node.js and Express. It defines middleware as functions that have access to the request and response objects and can run code and make changes to these objects before the next middleware in the chain. It discusses common uses of middleware like logging, authentication, parsing request bodies. It also covers Connect middleware and how Express builds on Connect by adding features like routing and views. Key aspects covered include the middleware pipeline concept, error handling with middleware, and common middleware modules.
The document provides information on various web server software, web application servers, HTTP requests and responses, and the differences between web servers and application servers. It also discusses servlets, web applications, and the servlet API. Specifically, it lists popular web server software like Apache HTTP Server, Microsoft IIS, and Apache Tomcat. It explains how web application servers extend web servers to support dynamic content through templates, programs, and databases. It also defines the key components of HTTP requests and responses.
This document provides information on Java servlets including: what servlets are and their advantages; the servlet architecture and lifecycle including initialization, processing requests via doGet and doPost methods, and destruction; how to deploy servlets in an application server; and how servlets handle form data submission. Servlets act as a middle layer between web requests and applications/databases, and allow dynamically generating web pages.
What is an RPA CoE? Session 1 – CoE VisionDianaGray10
In the first session, we will review the organization's vision and how this has an impact on the COE Structure.
Topics covered:
• The role of a steering committee
• How do the organization’s priorities determine CoE Structure?
Speaker:
Chris Bolin, Senior Intelligent Automation Architect Anika Systems
Essentials of Automations: Exploring Attributes & Automation ParametersSafe Software
Building automations in FME Flow can save time, money, and help businesses scale by eliminating data silos and providing data to stakeholders in real-time. One essential component to orchestrating complex automations is the use of attributes & automation parameters (both formerly known as “keys”). In fact, it’s unlikely you’ll ever build an Automation without using these components, but what exactly are they?
Attributes & automation parameters enable the automation author to pass data values from one automation component to the next. During this webinar, our FME Flow Specialists will cover leveraging the three types of these output attributes & parameters in FME Flow: Event, Custom, and Automation. As a bonus, they’ll also be making use of the Split-Merge Block functionality.
You’ll leave this webinar with a better understanding of how to maximize the potential of automations by making use of attributes & automation parameters, with the ultimate goal of setting your enterprise integration workflows up on autopilot.
[OReilly Superstream] Occupy the Space: A grassroots guide to engineering (an...Jason Yip
The typical problem in product engineering is not bad strategy, so much as “no strategy”. This leads to confusion, lack of motivation, and incoherent action. The next time you look for a strategy and find an empty space, instead of waiting for it to be filled, I will show you how to fill it in yourself. If you’re wrong, it forces a correction. If you’re right, it helps create focus. I’ll share how I’ve approached this in the past, both what works and lessons for what didn’t work so well.
"Choosing proper type of scaling", Olena SyrotaFwdays
Imagine an IoT processing system that is already quite mature and production-ready and for which client coverage is growing and scaling and performance aspects are life and death questions. The system has Redis, MongoDB, and stream processing based on ksqldb. In this talk, firstly, we will analyze scaling approaches and then select the proper ones for our system.
HCL Notes und Domino Lizenzkostenreduzierung in der Welt von DLAUpanagenda
Webinar Recording: https://www.panagenda.com/webinars/hcl-notes-und-domino-lizenzkostenreduzierung-in-der-welt-von-dlau/
DLAU und die Lizenzen nach dem CCB- und CCX-Modell sind für viele in der HCL-Community seit letztem Jahr ein heißes Thema. Als Notes- oder Domino-Kunde haben Sie vielleicht mit unerwartet hohen Benutzerzahlen und Lizenzgebühren zu kämpfen. Sie fragen sich vielleicht, wie diese neue Art der Lizenzierung funktioniert und welchen Nutzen sie Ihnen bringt. Vor allem wollen Sie sicherlich Ihr Budget einhalten und Kosten sparen, wo immer möglich. Das verstehen wir und wir möchten Ihnen dabei helfen!
Wir erklären Ihnen, wie Sie häufige Konfigurationsprobleme lösen können, die dazu führen können, dass mehr Benutzer gezählt werden als nötig, und wie Sie überflüssige oder ungenutzte Konten identifizieren und entfernen können, um Geld zu sparen. Es gibt auch einige Ansätze, die zu unnötigen Ausgaben führen können, z. B. wenn ein Personendokument anstelle eines Mail-Ins für geteilte Mailboxen verwendet wird. Wir zeigen Ihnen solche Fälle und deren Lösungen. Und natürlich erklären wir Ihnen das neue Lizenzmodell.
Nehmen Sie an diesem Webinar teil, bei dem HCL-Ambassador Marc Thomas und Gastredner Franz Walder Ihnen diese neue Welt näherbringen. Es vermittelt Ihnen die Tools und das Know-how, um den Überblick zu bewahren. Sie werden in der Lage sein, Ihre Kosten durch eine optimierte Domino-Konfiguration zu reduzieren und auch in Zukunft gering zu halten.
Diese Themen werden behandelt
- Reduzierung der Lizenzkosten durch Auffinden und Beheben von Fehlkonfigurationen und überflüssigen Konten
- Wie funktionieren CCB- und CCX-Lizenzen wirklich?
- Verstehen des DLAU-Tools und wie man es am besten nutzt
- Tipps für häufige Problembereiche, wie z. B. Team-Postfächer, Funktions-/Testbenutzer usw.
- Praxisbeispiele und Best Practices zum sofortigen Umsetzen
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Monitoring and Managing Anomaly Detection on OpenShift
Overview
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Key Topics Covered
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12. Jupyter Notebooks with Code Examples
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3. To create a simple HTTP server in Java
To use the implementation to illustrate a
number of advanced Java features:
› TCP/IP Sockets and Server Sockets
› Interfaces
› Software components (more from John later)
› Multithreading
To show how to create executable
server objects (using Sun’s Servlets API)
4. Java Network Programming, Elliotte
Rusty Harold, O’Reilly and Associates,
1997, ISBN 1-56592-227-1
TCP/IP Network Administration, Second
Edition, Craig Hunt, O’Reilly and
Associates, 1997, ISBN 1-56592-322-7
The Java Developer’s connection:
http://www.javasoft.com/jdc
The Javadoc documentation
5. Server must be able to process HTTP/1.0
file transfer requests and deliver files
Connections are to be made via TCP/IP
Must be efficient and prompt
Must be simple to understand and
elegant in design
6. Developed by Tim Berners-Lee at CERN
Like most Internet protocols it is
described in an RFC (Request for
Comment document): RFC1945
May be downloaded from the Internet
Engineering Task Force’s web site:
http://www.ietf.org
7. Some of you may have covered this in
the introductory Java course
Servers have a listener loop
› Loop until the server is shutdown
Wait for a client to request a connection
Read the details of the client’s request
Provide the requested information to the client
Here’s the listener loop from our
example:
8. ServerSocket socket = new ServerSocket(80, 5);
public void listen()
throws IllegalAccessException,
InstantiationException,
IOException
{
for (;;) {
System.err.println("HttpServer: waiting...");
Socket s = socket.accept();
FileServer f = createFileServer();
f.dispatch(s);
}
}
9. 2037 80
2037 1583
2037 1583
Client (sid) Server (fred)
ServerSocket ss.
s = ss.accept()
s = new Socket
(“fred”, 80)
Socket s
s.getInputStream()
s.getOuputStream()
s.getInputStream()
s.getOuputStream()
10. Good software is designed in a modular
fashion avoiding stovepipe designs!
This is a form of software components
Java has strong support for components
Components hide their implementation
behind interfaces
An interface defines a contract between
the supplier/server and the user/client.
11. ServerSocket socket = new ServerSocket(80, 5);
public void listen()
throws IllegalAccessException,
InstantiationException,
IOException
{
for (;;) {
System.err.println("HttpServer: waiting...");
Socket s = socket.accept();
FileServer f = createFileServer();
f.dispatch(s);
}
}
12. Simplifies client implementation
Clients do not need to worry about the
implementation details
Interfaces encapsulate state of different
subsystems ⇒ side effects reduced
Define clear boundaries between different
teams of programmers
Clients can substitute alternative
implementations: polymorphism
Clients can purchase off the shelf solutions:
software components
13. Software Component
Client Program
Interface /ublic class HttpServer
{
/**
Listens indefinitely for transfer requests and creates a server
instance for each request.
*/
public void listen()
throws IllegalAccessException, InstantiationException, IOException
{
for (;;) {
/*
Block, waiting for a request to occur then spawns a new
(anonymous) socket with which to deal with the request.
*/
System.err.println("HttpServer: waiting...");
Socket s = socket.accept();
/*
Create a file server to deal with the new socket.
*/
FileServer f = createFileServer();
f.dispatch(s);
}
}
public static void main(String[] args)
{
try {
HttpServer htts = new HttpServer("sea.server.ThreadedFileServer");
htts.listen();
}
catch (Exception e) {
System.err.println("HttpServer: failed due to exception:n" + e);
}
}
14. public interface FileServer
{
/**
This method allows an incoming HTTP request to initiate a
file dispatch. The socket will provide an input stream (which
is at the beginning) from which an HTTP/1.0 header request may
be read.<p>
It also provides an output stream on which the request should be
delivered. The delivery should have an HTTP/1.0 header
prepended.
@param s The socket on which a request is being made.
Once this method has returned the socket will have
been closed by the dispatcher.
*/
public void dispatch(Socket s);
}
15. Each interface is a contract between
two parties
The contract should be made as strict
and precise as possible
Avoid unnecessary ambiguity
Document the contract within the
interface’s source file using Javadoc
16. Two flavours of FileServer have been
provided using deferred instantiation
› A simple one but with low performance:
sea.server.SimpleFileServer
› A server that uses multiple threads to
increase performance:
sea.server.ThreadedFileServer
› A server which uses a pool of threads to
achieve the maximum possible
performance: sea.server.ThreadedServer2
17. Must implement the FileServer interface
so that it can plug in to the HttpServer
Reads the HTTP request from the Socket’s
input stream
Decides which file is required
Reads the file and spools to the Socket’s
output stream.
18. public class SimpleFileServer implements FileServer
{
protected Socket s = null;
public void dispatch(Socket s)
{
this.s = s;
respond();
}
. . . .
}
19. Must get an input stream so that we
can analyse the request
Socket provides the method
› InputStream getInputStream();
Socket s;
InputStream inStream = s.getInputStream();
InputStreamReader reader = new InputStreamReader(inStream);
BufferedReader input = new BufferedReader(reader);
20. Request consists of a number of lines of
text separated by “rn”
First line is all this server is interested in
A typical request might be of the form:
GET /path/to/file.html HTTP/1.0
Accept: text/html
Accept: image/gif
User-Agent: Lynx/2.4
21. Cuts out the file name
Looks for the file relative to the current
working directory (not portable!!)
If the file is a directory look for the file
“index.html” in the directory
If the file does not exist then respond with
an error (code 404)
22. Must construct a header for the response
Code 200 means success
Simple header takes the following form:
HTTP/1.0 200 OK
Server: SEA/1.0
MIME-version: 1.0
Content-type: text/html
Data starts after blank line. . .
More data, etc. . .
23. Get the output stream from the Socket
› OutputStream getOutputStream()
Spool (copy) the file contents into the
socket
If the MIME type is textual then we must
make sure the lines are delimited by
“rn”.
Otherwise we pass the file unmodified
24. The SimpleFileServer is completely
sequential.
› It handles one request at a time.
Reading a file from disk takes a long time
(around 10ms)
The server will be sitting idle while it waits
for the file to load (wasting up to 106
instruction cycles)
Other web browsers will be kept waiting
25. Start HTTP request loading
Block awaiting disk availability
Deliver web page across network
time
26. Threaded servers can process several
requests at once. Each request is
handled by a separate thread.
This doesn’t increase the overall amount
of work done (unless using SMP)
. . . but it does reduce the wastage!
Threaded operation is worthwhile when
threads are expected to block, awaiting
I/O operations
27. Start HTTP request loading
Block awaiting disk availability
Deliver web page across network
time
28. Java provides very convenient
multithreading to programmers
We can add threads using inheritance
› We can supplement the existing capabilities
of the SimpleFileServer class
› We create a class ThreadedFileServer which
extends the existing SimpleFileServer
You may have covered threads in the
Introductory Java Course
29. public class ThreadedFileServer extends SimpleFileServer
implements FileServer, Runnable
{
private static int index = 0;
public void dispatch(Socket s) {
super.s = s;
Thread thread =
new Thread(this, ”Server-" + (index++));
thread.start();
}
public void run() {
super.respond();
}
}
30. Creates new threads within the virtual
machine
Classes which start threads must
implement interface java.lang.Runnable
interface Runnable
{
/**
This is the method that will be run when the
new thread is started.
*/
public void run();
}
31. Must create a Thread object associated
with each new thread using the
constructor
› Thread(Runnable run, String threadName)
Start a thread with the method
› void start()
Other useful methods can be used to set
priorities and interrupt a running thread
32. Our threads do not share any common
memory locations (except for index)
When threads read/write a shared
memory area access must be
synchronized
Otherwise it is impossible to predict how
the system will behave
Java has mechanisms for achieving this
33. Starting a thread can be relatively
expensive when performance is critical
Our threaded server creates a new Thread
for each file to be transferred
A better approach is to create a pool of
threads and recycle them
› Create a pool of threads which are ready to
work when needed
› Have threads wait until work is available
Better, but more complex so look at the
class sea.server.ThreadedFileServer2
34. Our example web server performs a very
simple task
› Accept a request from a client
› Retrieve the appropriate document from disk
› Return the document to the client
This is too limiting
› How do we implement searches?
We need to be able to run programs within
the server to process user requests
› Accept a client request including arguments
› Run a program on the arguments
› Return results in the form of a document
35. When we run small Java programs within a
browser these are referred to as Applets. . .
so we run small Java programs within a
server these are “Servlets”
A servlet is a program designed to process
a client request (which requires
interactivity).
› It processes arguments and formats its results as
a short lived document.
HTML servlets are becoming a popular
mechanism for creating interactive servers.
36. Traditionally programs were run on web
servers using Common Gateway
Interface (CGI) scripts written in
languages such as Perl.
› Must create a new interpreter process for
each client request
› Comparatively slow to start
› Expensive of memory resources when serving
several clients at the same time
› Interpreted programs are CPU intensive
37. Servlets use Java objects which persist
between requests to the server
› Low latency since requests run in threads
› Offer performance advantages since programs
are compiled and can take advantage of JITs
and/or Hotspot JVMs.
› Servlet groups can share a JVM leading to
smaller memory footprints.
› Servlets run in a Sandbox offering protection
from malicious (or accidental) damage
› Programs are future proofed since WORA offers
better scope for server upgrades.
38. Servlets are written in a similar fashion to
applets
› Write a new servlet class which extends
javax.servlet.http.HttpServlet (or just
implements javax.servlet.Servlet)
› Override certain methods to deal with requests
› Get your methods to create an HTML document
to return information to the client’s browser
› Load the servlet byte codes onto your web
server (for example apache/jserv)
39. When the servlet is first loaded it makes a
single call to the method
› public void init(ServletConfig config)
This may optionally be overridden to initialise
the state of the servlet (for example loading
state information from a file).
When a servlet is finally unloaded it
makes a single call to the method
› public void destroy()
If you wish to save to servlet state to a file (or
using JDBC) this is the method to override
40. To handle an HTTP GET request implement
› protected void doGet(HttpServletRequest request,
HttpServletResponse response)
If a browser visits your servlet this is where you get
to create a document for it to display
To handle an HTTP POST request provide
› protected void doPost(HttpServletRequest request,
HttpServletResponse response)
If your document contains an HTML form and the
user posts the results this is where you can extract
and process them
Also methods for HTTP OPTIONS, TRACE and
DELETE (more exotic options)
41. Two objects are passed as parameters to all
these handler methods:
javax.servlet.http.HttpServletRequest
› Represents the formation that was passed to the
server when the user submitted the request by
visiting/posting to the servlets URL.
javax.servlet.http.HttpServletResponse
› Used to construct a reponse document that is
returned to the user
Each has a raft of methods so check the
Javadoc for details
42. An web based chat room server
A number of users can connect to the
servlet using browsers
Read a list of the previous messages
Optionally append new messages to the list
Messages are attributed to a specific
author and are time stamped
Messages do not persist after the chat
server is stopped (easy enough to rectify)
43. public class ChatServlet extends HttpServlet
{
Vector messages = new Vector();
public void init(ServletConfig config)
throws ServletException
{
super.init(config);
}
public void destroy()
{
// Currently does nothing
}
. . . .
}
44. protected void doGet(HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException {
createDocument(response);
}
protected void createDocument(HttpServletResponse response)
throws IOException {
response.setContentType("text/html");
response.setHeader("pragma", "no-cache");
PrintWriter writer = response.getWriter();
writer.println("<HTML>");
writer.println("<HEAD><TITLE>Chat Servlet</TITLE></HEAD>");
writer.println("<BODY>");
Date now = new Date();
writer.println("Current server time is " + now + "<P>");
. . . .
writer.println("</BODY></HTML>");
writer.close();
}
45. for (int i = 0; i < messages.size(); i++) {
writer.println("<HR>");
String messageString = (String) messages.elementAt(i);
writer.println(messageString);
}
writer.println("<HR><FORM METHOD=POST>");
writer.println("Enter your name: “ +
“<INPUT TYPE=TEXT SIZE=25 NAME=name><BR>");
writer.println("Enter your message:<BR>” +
“<TEXTAREA ROWS=5 COLS=40 NAME=message>” +
“Type your message here</TEXTAREA><BR>");
writer.println(
"<INPUT TYPE=SUBMIT NAME=action VALUE=Submit>");
writer.println("<HR></FORM>");
46. protected synchronized void doPost(
HttpServletRequest request,
HttpServletResponse response)
throws ServletException, IOException
{
String name = request.getParameter("name");
String message = request.getParameter("message");
if (name != null && message != null) {
Date timeStamp = new Date();
String messageString = "<B>Message " + messages.size() +
" from " + name + " at " + timeStamp +
":</B><BR>" + message + "<P>";
messages.add(messageString);
}
createDocument(response);
}
47. Servlets offer better performance than most
of the previous CGI like technologies
But CGI/Servlets concentrate the load on
the server
When designing high throughput servers
only use servlets where you really need
interactivity
› Searches/Shopping carts
› Data that is very short lived (stock quotes)
This also applies to low throughput servers
that might need to scale later
48. Consider using periodic programs to
generate static documents on disk
› The cost of serving fixed documents will always
be less than the cost of server side execution
› Disk space is cheap!
Consider using applets when possible
› This places the load on the client machines
rather than the server
Finally consider using SMP and/or server
farms
› Complex and very expensive
49. How can a chat reader find out when a
new message has been posted by another
author?
› Only by repeatedly hitting the Reload button!
HTTP (& TCP/IP services in general) transfer
documents on the user’s request
To push updates automatically from the
server you will need to:
› Start a reverse server within each client
› Use a multicast group
› Use a remote procedure call system such as RMI
or CORBA
50. Java Server Pages is an extension to the
servlets API.
With conventional servlets you embed the
HTML that you need inside a Java program.
With JSP you embed your Java program
within a HTML document (by using special
tags).
Works rather like JavaScript but the JSP
script runs on the server before the page is
dispatched to the user’s browser.
51. For information about HTML try
http://www.w3schools.com
You can download Sun’s servlet
development kit from their web site at
the http://java.sun.com/products/servlet
You can download apache’s Tomcat
server from http://jakarta.apache.org
For other information about Servlet
development try
http://www.servlets.com
52. Read through the sample code to
convince yourself you understand what’s
going on
Sample code can be downloaded from
http://ciips.ee.uwa.edu.au/~gareth
Read the code documentation
If you can, run the examples to check
they work