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Introduction

You should use doGet() when you want to intercept on HTTP GET requests. You should use doPost() when you want to intercept on HTTP POST requests. That's all. Do not port the one to the other or vice versa (such as in Netbeans' unfortunate auto-generated processRequest() method). This makes no utter sense.

GET

Usually, HTTP GET requests are idempotent. I.e. you get exactly the same result everytime you execute the request (leaving authorization/authentication and the time-sensitive nature of the page —search results, last news, etc— outside consideration). We can talk about a bookmarkable request. Clicking a link, clicking a bookmark, entering raw URL in browser address bar, etcetera will all fire a HTTP GET request. If a Servlet is listening on the URL in question, then its doGet() method will be called. It's usually used to preprocess a request. I.e. doing some business stuff before presenting the HTML output from a JSP, such as gathering data for display in a table.

@WebServlet("/products

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ServletContext

When the servletcontainer (like Apache Tomcat) starts up, it will deploy and load all webapplications. When a webapplication get loaded, the servletcontainer will create the ServletContext once and keep in server's memory. The webapp's web.xml will be parsed and every <servlet>, <filter> and <listener> found in web.xml, or annotated with respectively @WebServlet, @WebFilter and @WebListener, will be created once and kept in server's memory as well. For all filters, the init() method will also be invoked immediately. When the servletcontainer shuts down, it will unload all webapplications, invoke the destroy() of all initialized servlets and filters, and finally the ServletContext and all Servlet, Filter and Listener instances will be trashed.

When the Servlet in question has a <servlet><load-on-startup> or @WebServlet(loadOnStartup) value greater than 0, then its init() method will also immediately be invoked during startup. Those servlets are initialized in the same order as "load-on-startup

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<url-pattern>/*</url-pattern>

The /* on a servlet overrides all other servlets, including all servlets provided by the servletcontainer such as the default servlet and the JSP servlet. Whatever request you fire, it will end up in that servlet. This is thus a bad URL pattern for servlets. Usually, you'd like to use /* on a Filter only. It is able to let the request continue to any of the servlets listening on a more specific URL pattern by calling FilterChain#doFilter().

<url-pattern>/</url-pattern>

The / doesn't override any other servlet. It only replaces the servletcontainer's builtin default servlet for all requests which doesn't match any other registered servlet. This is normally only invoked on static resources (CSS/JS/image/etc) and directory listings. The servletcontainer's builtin default servlet is also capable of dealing with HTTP cache requests, media (audio/video) streaming and file download resumes. Usually, you don't want to override the default servlet as you would otherwise have to take ca

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http://docs.oracle.com/cd/E13222_01/wls/docs92/webapp/basics.html
http://docs.roguewave.com/hydraexpress/3.5.0/html/rwsfservletug/4-7.html
http://javabeat.net/spring-mvc-application-context/
http://www.programcreek.com/
https://netbeans.org/kb/docs/javaee/ecommerce/intro.html#about
https://docs.jboss.org/author/display/JBWS/Web+Services+Introduction
http://www.javatips.net/
http://www.sanfoundry.com/

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I have solved this issue by below steps:

    Right click the Maven Project -> Build Path -> Configure Build Path
    In Order and Export tab, you can see the message like '2 build path entries are missing'
    Now select 'JRE System Library' and 'Maven Dependencies' checkbox
    Click OK

Now you can see below in all type of Explorers (Package or Project or Navigator)

src/main/java

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To list all local users you can use:

cut -d: -f1 /etc/passwd

To list all users capable of authenticating (in some way), including non-local, see this reply: http://askubuntu.com/a/414561/571941

Some more useful user-management commands (also limited to local users):

To add a new user you can use:

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Info:
Description Resource Path Location Type Could not calculate build plan: Failure to transfer org.apache.maven.plugins:maven-compiler-plugin:pom:2.0.2 from http://repo1.maven.org/maven2 was cached in the local repository, resolution will not be reattempted until the update interval of central has elapsed or updates are forced. Original error: Could not transfer artifact org.apache.maven.plugins:maven-compiler-plugin:pom:2.0.2 from/to central (http://repo1.maven.org/maven2): No response received after 60000 ExampleProject Unknown Maven Problem

---------------------------------------------------Answer---------------------------------------------------

Remove all your failed downloads:

For *nix
find ~/.m2  -name "*.lastUpdated" -exec grep -q "Could not transfer" {} \; -print -exec rm {} \;

ToanPV90

First of all, the term "redirect" is in web development world the action of sending the client an empty HTTP response with just a Location header with therein the new URL on which the client has to send a brand new GET request. So basically:

    Client sends a HTTP request to some.jsp.
    Server sends a HTTP response back with Location: other.jsp header
    Client sends a HTTP request to other.jsp (this get reflected in browser address bar!)
    Server sends a HTTP response back with content of other.jsp.

You can track it with the webbrowser's builtin/addon developer toolset. Press F12 in Chrome/IE9/Firebug and check the "Network" section to see it.

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Note: I am using Ubuntu Linux.

    – Close Eclipse
    – Go to your Eclipse workspace directory
    – Then go to directory .metadata/.plugins/org.eclipse.core.runtime/.settings
    – In Ubuntu, I do it by: cd ~/workspace/.metadata/.plugins/org.eclipse.core.runtime/.settings
    – Delete the following two files:
    – org.eclipse.wst.server.core.prefs
    – org.eclipse.jst.server.tomcat.core.prefs
    – You can do it by the following command:

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How To Uninstall tomcat7 On Ubuntu 15.04

To uninstall tomcat7 just follow these instructions.
Are you having problems? You can always add tomcat7again by following the instructions at this link.
Uninstall just tomcat7

      `sudo apt-get remove tomcat7`

This will remove just the tomcat7 package itself.
Uninstall tomcat7 and it's dependencies