Servlet returns HTTP Status 404 The requested resource servlet is not available

Question

I have an HTML form in a JSP file in my WebContent jsps folder  I have a servlet class servlet java in my default package in src folder  In my web xml it is mapped as  servlet  I have tried several URLs in action attribute of the HTML form   lt form action  quot  servlet quot  gt    lt form action  quot  servlet java quot  gt    lt form action  quot  src servlet java quot  gt    lt form action  quot    servlet java quot  gt   But none of those work  They all keep returning a HTTP 404 error like below in Tomcat 6 7 8   HTTP Status 404      servlet Description  The requested resource   servlet  is not available   Or as below in Tomcat 8 5 9   HTTP Status 404     Not Found Message   servlet Description  The origin server did not find a current representation for the target resource or is not willing to disclose that one exists  Why is it not working

User · Answer

The fix that worked for me is if you are using Maven   Rightclick your project  Maven -  Update project  This might give you some other error with the JDK and other Libraries in my case  MySQL connector   but once you fix them  your original problem should be fixed

User · Answer

If you are a student and new to Java there might be some issue going on with your web xml file    Try removing the web xml file  Secondly check that your path variables are properly  set or not  Restart tomcat server Or your PC    Your problem will be surely solved

User · Answer

Scenario  1  You accidentially re-deployed from the command line while tomcat was already running   Short Answer  Stop Tomcat  delete target folder  mvn package  then re-deploy    Scenario  2  request getRequestDispatcher  MIS SPELLED FILE NAME jsp    Short Answer  Check file name spelling  make sure case is correct     Scenario  3  Class Not Found Exceptions  Answer put here because  Question  17982240     java lang ClassNotFoundException for servlet in tomcat with eclipse    was marked as duplicate and directed me here    Short Answer  3 1  web xml has wrong package path in servlet-class tag   Short Answer  3 2  java file has wrong import statement     Below is further details for Scenario  1     1  Stop Tomcat   Option 1  Via CTRL C in terminal  Option 2   terminal closed while tomcat still running  ------------ 2 1  press Windows R --  type  services msc  ------------ 2 2  Find  Apache Tomcat     Tomcat   in Name column of list  ------------ 2 3  Right Click --   stop    2  Delete the  target  folder   mvn clean will not help you here   3  mvn package  4  YOUR DEPLOYMENT COMMAND HERE   Mine  java -jar target dependency webapp-runner jar --port 5190 target   war    Full Back Story     Accidentially opened a new git-bash window and tried to deploy a  war file for my heroku project via   java -jar target dependency webapp-runner jar --port 5190 target   war  After a failure to deploy  I realized I had two git-bash windows open  and had not used CTLR C to stop the previous deployment   I was met with      HTTP Status 404     Not Found Type Status Report      Message  if-student-test jsp      Description The origin server  did not find a current representation   for  the target resource or is not willing  to disclose that one   exists       Apache Tomcat 8 5 31   Below is further details for Scenario  3     SCENARIO 3 1     The servlet-class package path is wrong     in your web xml file   It should MATCH the package statement at top    of your java servlet class   File  my stuff MyClass java      package my stuff    File  PRJ ROOT src main webapp WEB-INF web xml      lt servlet-class gt     my stuff MyClass     lt  servlet-class gt    SCENARIO 3 2   You put the wrong  package  statement    at top of your myClass java file   For example   File is in    my stuff  folder  You mistakenly write   package com my stuff   This is tricky because   1  The maven build  mvn package  will not report any errors here   2  servlet-class line in web xml can have CORRECT package path  E g    lt servlet-class gt  my stuff MyClass  lt  servlet-class gt      Stack Used  Notepad     GitBash   Maven   Heroku Web App Runner   Tomcat9   Windows10

User · Answer

Introduction This can have a lot of causes which are broken down in following sections   Put servlet class in a package Set servlet URL in url-pattern  WebServlet works only on Servlet 3 0 or newer javax servlet   doesn t work anymore in Servlet 5 0 or newer Make sure compiled   class file is present in built WAR Test the servlet individually without any JSP HTML page Use domain-relative URL to reference servlet from HTML Use straight quotes in HTML attributes  Put servlet class in a package First of all  put the servlet class in a Java package  You should always put publicly reuseable Java classes in a package  otherwise they are invisible to classes which are in a package  such as the server itself  This way you eliminiate potential environment-specific problems  Packageless servlets work only in specific Tomcat JDK combinations and this should never be relied upon  In case of a  quot plain quot  IDE project  the class needs to be placed in its package structure inside  quot Java Resources quot  folder and thus not  quot WebContent quot   this is for web files such as JSP  Below is an example of the folder structure of a default Eclipse Dynamic Web Project as seen in Navigator view  EclipseProjectName   -- src        -- com             -- example                  -- YourServlet java   -- WebContent        -- WEB-INF             -- web xml        -- jsps             -- page jsp     In case of a Maven project  the class needs to be placed in its package structure inside main java and thus not main resources  this is for non-class files and absolutely also not main webapp  this is for web files   Below is an example of the folder structure of a default Maven webapp project as seen in Eclipse s Navigator view  MavenProjectName   -- src        -- main             -- java                  -- com                       -- example                            -- YourServlet java             -- resources             -- webapp                  -- WEB-INF                       -- web xml                  -- jsps                       -- page jsp     Note that the  jsps subfolder is not strictly necessary  You can even do without it and put the JSP file directly in webcontent webapp root  but I m just taking over this from your question  Set servlet URL in url-pattern The servlet URL is specified as the  quot URL pattern quot  of the servlet mapping  It s absolutely not per definition the classname filename of the servlet class  The URL pattern is to be specified as value of  WebServlet annotation  package com example     Use a package    WebServlet  quot  servlet quot      This is the URL of the servlet  public class YourServlet extends HttpServlet      Must be public and extend HttpServlet                In case you want to support path parameters like  servlet foo bar  then use an URL pattern of  servlet   instead  See also Servlet and path parameters like  xyz  value  test  how to map in web xml   WebServlet works only on Servlet 3 0 or newer In order to use  WebServlet  you only need to make sure that your web xml file  if any  it s optional since Servlet 3 0   is declared conform Servlet 3 0  version and thus not conform e g  2 5 version or lower  Below is a Servlet 4 0 compatible one  which matches Tomcat 9   WildFly 11   Payara 5   etc    lt  xml version  quot 1 0 quot  encoding  quot UTF-8 quot   gt   lt web-app     xmlns  quot http   xmlns jcp org xml ns javaee quot      xmlns xsi  quot http   www w3 org 2001 XMLSchema-instance quot      xsi schemaLocation  quot http   xmlns jcp org xml ns javaee http   xmlns jcp org xml ns javaee web-app 4 0 xsd quot      version  quot 4 0 quot   gt       lt  -- Config here  -- gt   lt  web-app gt   Or  in case you re not on Servlet 3 0  yet  e g  Tomcat 6 or older   then remove the  WebServlet annotation  package com example   public class YourServlet extends HttpServlet                 And register the servlet instead in web xml like this   lt servlet gt       lt servlet-name gt yourServlet lt  servlet-name gt       lt servlet-class gt com example YourServlet lt  servlet-class gt   lt  servlet gt   lt servlet-mapping gt       lt servlet-name gt yourServlet lt  servlet-name gt       lt url-pattern gt  servlet lt  url-pattern gt    lt  -- This is the URL of the servlet  -- gt   lt  servlet-mapping gt   Note thus that you should not use both ways  Use either annotation based configuarion or XML based configuration  When you have both  then XML based configuration will override annotation based configuration  javax servlet   doesn t work anymore in Servlet 5 0 or newer Since Jakarta EE 9   Servlet 5 0  Tomcat 10  TomEE 9  WildFly 22 Preview  GlassFish 6  Payara 6  Liberty 22  etc   the javax   package has been renamed to jakarta   package  In other words  please make absolutely sure that you don t randomly put JAR files of a different server in your WAR project such as tomcat-servlet-api-9 x x jar merely in order to get the javax   package to compile  This will only cause trouble  Remove it altogether and edit the imports of your servlet class from import javax servlet    import javax servlet http     to import jakarta servlet    import jakarta servlet http     In case you re using Maven  you can find examples of proper pom xml declarations for Tomcat 10   Tomcat 9-  JEE 9  and JEE 8- in this answer  Tomcat 9 casting servlets to javax servlet Servlet instead of jakarta servlet http HttpServlet Make sure compiled   class file is present in built WAR In case you re using a build tool such as Eclipse and or Maven  then you need to make absolutely sure that the compiled servlet class file resides in its package structure in  WEB-INF classes folder of the produced WAR file  In case of package com example  public class YourServlet  it must be located in  WEB-INF classes com example YourServlet class  Otherwise you will face in case of  WebServlet also a 404 error  or in case of  lt servlet gt  a HTTP 500 error like below   HTTP Status 500 Error instantiating servlet class com example YourServlet  And find in the server log a java lang ClassNotFoundException  com example YourServlet  followed by a java lang NoClassDefFoundError  com example YourServlet  in turn followed by javax servlet ServletException  Error instantiating servlet class com example YourServlet  An easy way to verify if the servlet is correctly compiled and placed in classpath is to let the build tool produce a WAR file  e g  rightclick project  Export  gt  WAR file in Eclipse  and then inspect its contents with a ZIP tool  If the servlet class is missing in  WEB-INF classes  or if the export causes an error  then the project is badly configured or some IDE project configuration defaults have been mistakenly reverted  e g  Project  gt  Build Automatically has been disabled in Eclipse   You also need to make sure that the project icon has no red cross indicating a build error  You can find the exact error in Problems  view  Window  gt  Show View  gt  Other      Usually the error message is fine Googlable  In case you have no clue  best is to restart from scratch and do not touch any IDE project configuration defaults  In case you re using Eclipse  you can find instructions in How do I import the javax servlet API in my Eclipse project  Test the servlet individually without any JSP HTML page Provided that the server runs on localhost 8080  and that the WAR is successfully deployed on a context path of  contextname  which defaults to the IDE project name  case sensitive    and the servlet hasn t failed its initialization  read server logs for any deploy servlet success fail messages and the actual context path and servlet mapping   then a servlet with URL pattern of  servlet is available at http   localhost 8080 contextname servlet  You can just enter it straight in browser s address bar to test it invidivually  If its doGet   is properly overriden and implemented  then you will see its output in browser  Or if you don t have any doGet   or if it incorrectly calls super doGet    then a  quot HTTP 405  HTTP method GET is not supported by this URL quot  error will be shown  which is still better than a 404 as a 405 is evidence that the servlet itself is actually found   Overriding service   is a bad practice  unless you re reinventing a MVC framework     which is very unlikely if you re just starting out with servlets and are clueless as to the problem described in the current question    See also Design Patterns web based applications  Regardless  if the servlet already returns 404 when tested invidivually  then it s entirely pointless to try with a HTML form instead  Logically  it s therefore also entirely pointless to include any HTML form in questions about 404 errors from a servlet  Use domain-relative URL to reference servlet from HTML Once you ve verified that the servlet works fine when invoked individually  then you can advance to HTML  As to your concrete problem with the HTML form  the  lt form action gt  value needs to be a valid URL  The same applies to  lt a href gt   You need to understand how absolute relative URLs work  You know  an URL is a web address as you can enter see in the webbrowser s address bar  If you re specifying a relative URL as form action  i e  without the http    scheme  then it becomes relative to the current URL as you see in your webbrowser s address bar  It s thus absolutely not relative to the JSP HTML file location in server s WAR folder structure as many starters seem to think  So  assuming that the JSP page with the HTML form is opened by http   localhost 8080 contextname jsps page jsp  and you need to submit to a servlet located in http   localhost 8080 contextname servlet  here are several cases  note that you can safely substitute  lt form action gt  with  lt a href gt  here    Form action submits to an URL with a leading slash       lt form action  quot  servlet quot  gt   The leading slash   makes the URL relative to the domain  thus the form will submit to     http   localhost 8080 servlet  But this will likely result in a 404 as it s in the wrong context    Form action submits to an URL without a leading slash       lt form action  quot servlet quot  gt   This makes the URL relative to the current folder of the current URL  thus the form will submit to     http   localhost 8080 contextname jsps servlet  But this will likely result in a 404 as it s in the wrong folder    Form action submits to an URL which goes one folder up       lt form action  quot    servlet quot  gt   This will go one folder up  exactly like as in local disk file system paths    thus the form will submit to     http   localhost 8080 contextname servlet  This one must work    The canonical approach  however  is to make the URL domain-relative so that you don t need to fix the URLs once again when you happen to move the JSP files around into another folder       lt form action  quot   pageContext request contextPath  servlet quot  gt   This will generate      lt form action  quot  contextname servlet quot  gt   Which will thus always submit to the right URL     Use straight quotes in HTML attributes You need to make absolutely sure you re using straight quotes in HTML attributes like action  quot     quot  or action       and thus not curly quotes like action           or action            Curly quotes are not supported in HTML and they will simply become part of the value  Watch out when copy-pasting code snippets from blogs  Some blog engines  notably Wordpress  are known to by default use so-called  quot smart quotes quot  which thus also corrupts the quotes in code snippets this way  On the other hand  instead of copy-pasting code  try simply typing over the code yourself  Additional advantage of actually getting the code through your brain and fingers is that it will make you to remember and understand the code much better in long term and also make you a better developer  See also   Our servlets wiki page - Contains some hello world examples How to call servlet class from HTML form doGet and doPost in Servlets How do I pass current item to Java method by clicking a hyperlink or button in JSP page   Other cases of HTTP Status 404 error   HTTP Status 404 - Servlet  ServletName  is not available HTTP Status 404 - The requested resource   ProjectName   is not available HTTP Status 404 - The requested resource     is not available JSP in  WEB-INF returns  quot HTTP Status 404 The requested resource is not available quot  Referencing a resource placed in WEB-INF folder in JSP file returns HTTP 404 on resource Browser can  39 t access find relative resources like CSS  images and links when calling a Servlet which forwards to a JSP

User · Answer

Solution for HTTP Status 404 in NetBeans IDE  Right click on your project and go to your project properties  then click on run  then input your project relative URL like index jsp   Project- gt Properties Click on Run Relative URL  index jsp  Select your project root URL

User · Answer

Please check context root cannot be empty   If you re using eclipse  right click  select properties  then web project settings  Check the context root cannot be empty

User · Answer

Mapping in web xml is what i have done  -  If there s another package made for new program then we must mention  -  packagename filename between opening and closing of servlet-class tag in xml file   If you are mapping your files in xml and they are not working or showing errors   then comment on the annotation line of code in the respective files   Both methods dont work with one another   so either i use annotation method of files mentioned when we create servlet or the way of mapping   then i delete or comment the annotation line  Eg    lt servlet gt      lt servlet-name gt s1 lt  servlet-name gt      lt servlet-class gt performance FirstServ lt  servlet-class gt      lt  servlet gt              lt servlet-mapping gt      lt servlet-name gt s1 lt  servlet-name gt      lt url-pattern gt  FirstServ lt  url-pattern gt      lt  servlet-mapping gt          lt servlet gt      lt servlet-name gt s2 lt  servlet-name gt      lt servlet-class gt performance SecondServ lt  servlet-class gt      lt  servlet gt          lt servlet-mapping gt      lt servlet-name gt s2 lt  servlet-name gt      lt url-pattern gt  SecondServ lt  url-pattern gt      lt  servlet-mapping gt    Commenting the annotation line of code in the respective file if mapping in xml is done     WebServlet  quot  FirstServ quot      WebServlet  quot  SecondServ quot

User · Answer

I removed the old web library such that are spring framework libraries  And build a new path of the libraries  Then it works

User · Answer

If you would like to open a servlet with javascript without using  form  and  submit  button  here is the following code   var button   document getElementById   lt  lt button-id gt  gt     button addEventListener  click   function       window location href    lt  lt full-servlet-path gt  gt    eg  http   localhost 8086 xyz servlet        Key   1  button-id   The  id  tag you give to your button in your html jsp file   2  full-servlet-path  The path that shows in the browser when you run the servlet alone

User · Answer

My issue was that my method was missing the  RequestBody annotation  After adding the annotation I no longer received the 404 exception

User · Answer

Check if you have entered the correct URL Mapping as specified in the Web xml For example  In the web xml  your servlet declaration maybe   lt servlet gt           lt servlet-name gt ControllerA lt  servlet-name gt           lt servlet-class gt PackageName ControllerA lt  servlet-class gt   lt  servlet gt    lt servlet-mapping gt           lt servlet-name gt ControllerA lt  servlet-name gt           lt url-pattern gt  theController lt  url-pattern gt   lt  servlet-mapping gt   What this snippet does is  lt url-pattern gt  theController lt  url-pattern gt will set the name that will be used to call the servlet from the front end  eg  form  through the URL  Therefore when you reference the servlet in the front end  in order to ensure that the request goes to the servlet  quot ControllerA quot   it should refer the specified URL Pattern  quot theController quot  from the form  eg   lt form action  quot theController quot  method  quot POST quot  gt   lt  form gt

User · Answer

If someone is here who is using MySQL and felt that the code was working the previous day and now it doesn t  then I guess you must open MySQL CLI or MySQL Workbench and just make the connection to the database once  Once it gets connected  then the database also gets connected to the Java Application  I used to get the Hibernate Dialect error stating something wrong with com mysql jdbc Driver  I think MySQL in some computers has a startup problem  This solved for me

User · Answer

Do the following two steps  I hope  it will solve the  404 not found  issue in tomcat server during the development of java servlet application   Step 1  Right click on the server in the server explorer tab - gt Properties- gt Switch Location from workspace metadata to tomcat server  Step 2  Double Click on the server in the server explorer tab - gt Select Use tomcat installation option inside server location menu

User · Answer

I was facing this issue too  I was receiving a 404 when accessing a URL pattern that I knew was linked to a Servlet  The reason is because I had 2 Servlets with their  WebServlet name parameter set as the same string   WebServlet name    quot ServletName quot   urlPatterns     quot  path quot    public class ServletName extends HttpServlet      WebServlet name    quot ServletName quot   urlPatterns     quot  other-path quot    public class OtherServletName extends HttpServlet     Both of the name parameters are the same  If you re using the name parameter  make sure they are unique compared to all other Servlets on your application

User · Answer

First of all  run your IDE as Admin  After that  right click the project folder -  Project Facets and make sure that the Java Version is set correct  On my PC   For Example 1 8  Now it should work    Don t just start your server  for example Wildfly  using the cmd  It has to be launched within the IDE and now visit your localhost URL  Example  http   localhost 8080 HelloWorldServlet HelloWorld

User · Answer

An old thread  but since I didn t find it elsewhere  here is one more possibility   If you re using servlet-api 3 0   then your web xml must NOT include metadata-complete  true  attribute    This tells tomcat to map the servlets using data given in web xml instead of using the  WebServlet annotation

[html] Servlet returns "HTTP Status 404 The requested resource (/servlet) is not available"

Examples related to html

Examples related to forms

Examples related to jsp

Examples related to servlets

Examples related to http-status-code-404