We can create a Java Tomcat Project in eclipse. As per my knowledge its a Java project with a WAR structure. I have searched a lot on web but did not get any satisfactory answer.
I want to know what is the need of Tomcat Project when Dynamic Web Project is there?
Are they different in project hierarchy only or there is any other difference?
Is it specific to Apache Tomcat i.e. can't be deployed on any other server like JBoss?
Thanks.
Related
I am familiar with Java as a language but not JSP and Spring framework. I am trying to load an existing project and using vim as my IDE.
Originally, when working on it using eclipse, I installed openjdk7-jdk, downloaded the tomcat7 server from its website and extracted to a location, imported project in current workspace, set up the tomcat for server environment. I was able to see the application in browser.
I am looking for a way to use vim, installing tomcat from official repos and then either set up a new host for this application or adding a context for the same. I have tried both the ways but still not able to make it work. I get the tomcat standard 404 error page.
This answer here says that this may work if I create a .war file and place it in the webapps folder. Is this the only way to run a spring based application?
After working in ASP.Net, ROR, Django, I am assuming Java also has similar deployment structure.
One thing is that Tomcat is not required for spring based applications. But if you are implementing J2EE application on Tomcat, make sure you have Spring context defined in your webapps web.xml (inside WEB-INF directory).
The Spring Application context must be initialized through your ServletContextListener implementation.
Oups, seems there a long way to heaven ... More seriously you must pass by several steps (that a nice IDE like Eclipse or Netbeans can hide from you) :
create the source files for the application - you spoke of vim it can be used for that step
compile and build the application to a .war - this step is almost mandatory but i would not dare avoid it as I explain below - you can use low level tools like javac but you really should use ant or maven here ; if you are lucky, there is already a pom.xml (maven) or build.xml (ant) in the sources
deploy the war to a tomcat
In theory, it should be possible to individually compile the java file into .class, build a full hierarchy by hand and put that manually in webapps folder of tomcat. But never do that - or at least never say that I adviced you to do it :-)
i have tomcat project the directory structure is
previously i was using tomcat server, whenever i modified .java files i used to build the project and restarted the server in eclipse through plugin than the changes would have taken effect.
Now in my company they changed from tomcat to weblogic since i am new to it, i used to build war file every time and deploy manually to check the changes.
Can any one tell me how to do hot deployment in web logic. i googled it but it says i need to change project type to dynamic project, that i cant do since it already in development.
is their better way just make changes to java file build and no need to restart the server through eclipse in weblogic 12c.
Eclipse IDE luna
weblogic 12c server
project type : tomcat project structure
I think how you doing that is a little old fashioned. With eclipse luna, tomcat 5.0 - tomcat 8.0 is well supported. And take some effort to turn your project into a 'Dynamic Web Project', in that way you will benifit a lot from the experience of other people.
For hot redeploying, you can try JRebel, it reload your changed java class without reloading the whole applcaition.But it's a commercial software, and I don't know a good and free alternative yet.
I guess a drawback of using such an awesome IDE like eclipse is that you miss the point for what happens behind the scenes of an application. I'm a ruby developer so not a java veteran. So I've been coding a project in java and using the spring framework for IOC and MVC. Can someone explain to me what is going on when I select run on server in eclipse? Because eventually I will be deploying this masterpiece of an application to a Linux server. Here is my setup. I am using Spring MVC 3 and the maven plugin in eclipse. In the pom.xml file, I have stuff like latest spring release version, log4j, spring mvc, spring context etc.
I have been testing my application on localhost using the handy option of run on server in the eclipse IDE. The server configuration in eclipse is pointing to the tomcat directory location for where I have installed tomcat 7. Please demystify what happens behind the scenes and what I will need to do if I want to deploy this application on a production server. The more detail the better. Thanks a ton in advance.
Deploying a web application to Tomcat is as simple as this (assuming Tomcat is installed)
Bundle your application in a .war with the correct format.
Move the generated .war file to the /webapps directory of your Tomcat installation folder.
Run the /bin/startup.[sh|bat] script in the Tomcat installation folder.
Note that there are intermediate steps you can do to configure the deployment, like changing your context path. Go through the Tomcat documentation for details.
In step 3, Tomcat will extract the .war contents to a directory in the /webapps folder with the same name as your .war file. It will use this as the context path. The script itself launches a java process by putting the WEB-INF/[class|lib|...] onto the classpath along with some Tomcat libraries.
So Eclipse basically does all the steps above for you.
Ultimately you are deploying an web application that means you are deploying a war file to the server. Regardless of using frameworks like spring, struts anything.
SO a web application request starts from web.xml file. SO for spring mvc application, you are mapping all request coming from browser to DispatcherServlet and then this guy is responsible to manage whole life cycle of your application.
For more details of how MVC works please see
http://docs.spring.io/spring/docs/3.2.x/spring-framework-reference/html/mvc.html
So in order to deploy your application (a war) on server first of all you have to create a war from your source code. You can go to traditional approach to use java given utility like using jar from command prompt or you can use ANT, GRADLE, MAVEN and such build tool that creates war for you in automated way.
Spring is not doing anything extra for you. I believe you to research a bit more on how these tools works.
Once a war is ready for you, you can simply go to tomcat UI and there you will find options to deploy your war.
I hope it helps you.
All the majic happens in two places.
The first is your 'Servers' directory in the root of your Eclipse Package Explorer. These are your server configuration files that Eclipse will use (mostly) when it creates a new server instance.
The second is in the ./metadata/.plugins/org.eclipse.wst.server.core/ file system directory in your Eclipse workspace. This is where the tomcat application is actually deployed by eclipse.
The Tomcat Documentation is pretty good actually and helps explain how to do deployments. FYI, I do not know many people that use the Manager, from my experience most people deploy their applications by hand.
I am new in spring.I imported one spring project in eclipse and try to run with apache tomcat but it is not running.There is no main method in project.It contains only controllers and models and one jsp page.When i tried to run as a java application is shows below dialog. Please help me.I tried all in google for how to run spring project but i can't understand.Please tell me how to do?
Assuming you have added tomcat to your eclipse.
If your project is pure java project then it will not show you the run on server option in eclipe. You need to change project facet and add dynamic web module to it then you can run it on tomcat server from eclipse.Basically project needs to be web project.
After doing above if it gives error or do not run properly, check your project deployment assembly and add projects webapps folder in eclipse.
you need to have a tomcat installed in your eclipse and run it on the server.
Here is a tutorial to do this
You need to install the Web Tools Platform, which has support for the usual Web-application tools.
I don't know if some one asked this but I have a problem that I am working on this tutorial Hello World Example with annotation driven Spring 3 MVC in Eclipse .Now I am very embarrassed to say that how can I make war file to deploy on tomcat. Please guide me in this regard. Thank you
P.S: Just to inform you that I have Tomcat 6.0 and eclipse indigo 3.7
You have many options depending on the environment you're using; the more simple ways can be:
for testing purpose you can reference a Tomcat installation inside your Eclipse in the Severs tab of the J2EE perspective and add your Dynamic Web Project to it; then you can control (start/stop/debug) your server from Eclipse
to build a war to deploy, you can right click the Dynamic Web Project and choose Export War File
I would recommend using Apache Maven as it will help you much as you project will get bigger and your will have a lot of dependencies. You can try it as Eclipse plugin (m2eclipse) or use it from command line.