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Hadoop Eclipse configuration

i am new to Hadoop,i successfully installed Hadoop 2.2.0 pseudo distributed mode and successfully executed some example programs like word count ,PI through command prompt ,now i want to practice some map reduce programs using eclipse ,so i installed Eclipse juno first but does not know how to configure eclipse for hadoop,can anyone tell steps to configure the Eclipse juno for hadoop 2.2.0.
Thanks in Advance.

It is easy to get Eclipse configured for Hadoop. Basically you need to setup the Build Path and configure Ant and Maven. There is a good write up Here Check that out and come back with any questions once you get started.
Even though the above link references Cloudera, the Eclipse configuration is the same as a manually installed Hadoop release as it relates to getting Eclipse working. You will need to follow steps 1 - 4 at least in order to get the correct Build Path, Ant configuration and Hadoop run time jars in the correct Path.
The easiest way to make sure you have configured Eclipse correctly is to create a Java project and copy/paste the wordcount java file into the project. Once saved take a look at any errors in the console. If you have everything correctly configured you will be able to compile worcount and should have wordcount.class in you projects bin dir

1.Build the project with maven(m2e plugin) and the required jar files in the classpath.
2.Export the jar for the project.
3.Use command line utility of Hadoop to execute the MapReduce Job.

JFreeChart Java JAR not running on a different machine

I have created an application using the JFreeChart library for use on another machine.
Previously I have developed applications with JFreeChart (using the same libraries) which has worked fine on other machines. The only difference is this machine is running Vista.
Please see below for the run-time exception I am getting:
The class that cannot be found, however, is located in the highlighted jar in the below image showing my imported libraries for the JAR. I have also established that this JAR is included in the manifest for the application. See below image:
So I very much need this to work and have no idea where to look next - or what is causing this problem!
Development machine Java version:
1.7.0_45
Target machine Java version:
1.7.0_45
Thanks in advance.

Check the Class-Path attribute in your JAR's manifest, which should contain entries like this:
Class-Path: lib/jfreechart-1.0.17.jar lib/jcommon-1.0.21.jar …
Also, examine dist/README.TXT in your NetBeans project folder, which should say something like this regarding libraries required by your project:
To run the project from the command line, go to the dist folder and
type the following:
java -jar "CISOnlineMonitor.jar"
To distribute this project, zip up the dist folder (including the lib folder)
and distribute the ZIP file.

This has nothing to do with os i belive.You dont have all the necessery libs within your jar.Try to open a jar and see if you have them in.Fact that you are able to run it on your maschine only proves that.Make executable jar with eclipse or whathever you use.And when it ask you for libs check -Extract required libraries into generated Jar.
if you dont know how to get to that point
File>Export>Java>Runnable Jar File> Runnable JAR File Specification.
Also right click on your project and check Your build path.
RightClick project>Properties>Java Build Path>Libraries
Make sure you have everything correct
EDIT-
As i see you use NetBeans im not sure exactly how to find all this there.Bud it will be very similiar.

Importing .war file using cmd

I'm developing an Installer for a project team to reduce the amount of work they have to do installing it manually.
We are using:
Windows 7 x64,
Eclipse Kepler
Right now I'm looking for a way to import a .war file using the commandline.
Is there any way to do this via cmd?

First of all, I would not recommend importing the source code from a file in Eclipse if you have a team of developers, as you would be giving everyone a version that will hardly be actual after some days of work. Using some repository (CVS, SVN, GIT) would be the way to go.
If you have your code in a central repository, then you could make a "Project Set" file in Eclipse wich can be imported easily to setup your whole workspace:
http://help.eclipse.org/juno/index.jsp?topic=%2Forg.eclipse.platform.doc.user%2Ftasks%2Ftasks-cvs-project-set.htm
This project set might have instructions on how to construct the Workspace based on checkouts of the repositories you need.
If you happen to work at a company that uses some X or Y old-fashioned Source Control tool (or worse, none at all), and you have no chances of implementing one that is compatible with Eclipse (like the three I stated above), then the time you are saving with automating the import of a war file will become irrelevant compared to the source code control issues you will be facing (or the team is facing already).

A WAR file is a ZIP file. If you need the content of the WAR you can use the tools for ZIP archives.

A workaround in case eclipse does not have any such options would be to
do a Import WAR through eclipse GUI
check what changes are made to workspace by eclipse (eg. folder created with exploded war file content, configuration files created by eclipse in the folder like .classpath for project folders etc)
Identify the steps and replicate the same through a batch file
Add a call to the batch file in eclipse launch short cut

There is no command line API I know to do this task for Eclipse just from command line, but with the right tools you can achieve what you want.
Please try this:
Straightforward approach that works with any GUI application. You can use AutoIt scripts for interaction with any application. The downside is that GUI may change more frequently than command line API.
Try to create Eclipse project with metadata and unpack WAR file in this project. It can be done, for instance, with Maven or Gradle. Those also can download all dependencies for you.

How to remove reference of a jar file in a java based web application?

I have a java based web application, which has certain java files and due to some need, i have added some jar files with in the project and made it project specific.
Now, While deploying them in production, I see, that the web file server (tomcat6) already has those jar files in its global library. Now, How do i remove reference of that jar file it, with out disturbing my code(which is working fine).
I saw in other article saying we just have to change the build path to refer the global library instead of local library.
Finally I have 2 questions.
How to do this?
If i'm working on windows and using path while configuring the build path, will it not be a problem if i deploy it in Unix environment.?
Please suggest. Also, its the problem with servlet-api.jar.
I use eclipse IDE. So how to perform these changes in eclipse?

Open your web project in eclipse and right click on the project. click on Properties and then choose build path and remove the jars you want to remove under the tab 'Libraries' and then export the war and deploy it in your tomcat6 server. if you want to run your web application in eclipse, you have to configure the server libraries by clicking 'Add Library' button in build path and then choose server runtime and choose the tomcat6 server configured in eclipse. Hope this helps

How to create a .exe file in netbeans?

I've created a project in netbeans and I want it to be runnable in another computer without having the netbeans installed (just like a .exe in visual basic).
I pressed F11 and I got a lib folder which has a .jar file on it. But then I don't know how to work it out, which one do I have to double click?
Can anyone please guide me?

If you created a java project, then the "other" computer should have the java runtime installed, in order for the jar to be executed there (java -jar your.jar) otherwise if you really want an .exe use one of the many jar2exe converters found on the almighty internet, such as http://www.ucware.com/jexec/index.htm

To run jar file on other computer you should have at least jdk. Their is no need to install NetBeans but you have to first set database connectivity to pc and your database. After connectivity just double click on jar file your project will run.
To know how to create Jar file in NetBeans check this link.

What type of project is this Desktop application OR Web based application ? If you are using java then for Desktop application you need to create a *.JAR and for Web based : *.WAR.
There are simple step to create jar/ war. please follow any tutorial.