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.
Related
My team is working on a Java application that runs on Jboss WildFly, using Maven to resolve dependencies and Primefaces.
We're using Eclipse to build, deploy and run the server. Eclipse does most of the work, building the WAR file, deploying it to server and running it.
Now we need to create an script that performs all those steps because it has to run on remote server.
.
The steps would be something like this...
1 Run Maven:
$M2_HOME/bin/mvn clean install
2 Build project to a war file
3 Deploy war file into the WildFly deployment folder
$WILDFLY_HOME/bin/jboss-cli.sh --connect --command="deploy --force [PATH_TO_WAR]"
4 Start server
$WILDFLY_HOME/bin/standalone.sh
.
I can perform every step but once the server is running it don't seem to be any changes in the application. I think this is because the WAR file has to be built optimizing it for JBoss. Eclipse has a way to do this when exporting the project. I need to know how to do that from command.
EDIT:
The real problem is that Jboss is not updating the published project when i run it from bash script. I thought it was because i had to build it on a specific way. I was wrong. The build is fine, just running Maven the deploy is done. The thing is that even if i rebuild project and redeploy it, server doesn't seem to notice at all.
I've tried deleting tmp, lib and data folders from standalone folder, and nothing happens. I also deleted standalone/deployed sub files and folders and got the same result.
The only way i achieve the result i'm expecting is getting into Eclipse, go to Servers tab, right click on JBoss Wildfly and click on 'Clean...'. This options seems to clean cache, rebuild and re publish the application in a right way that i don't know. I didn't find any answers on google.
eclipse server clean option
Give a look on Eclipse war export: optimize for a specific server runtime.
Quoting from #Konstantin Komissarchik's answer :
Eclipse itself doesn't do anything with that option. What happens is
dependent on a particular server adapter. Many of the adapters don't
do anything with this option either, but they might in the future.
If a server adapter does support export optimization, it has the
option of displaying custom options beneath that pop-up list of
runtimes, so that's a good cue to use to see if something will
actually happen.
So taking in consideration that in your provided image there is no custom options below Wildfly 9 selection, I am pretty sure that this option does not perform any optimization at your exported war so you can totally omit it in your new build-deploy process.
How can i build the war file from command, knowing it will have to run on Wildfly?
We are also deploying applications for a long time on several versions of Widlfy with the same approach as you are planning to, without the optimization thing. I can ensure you that we have not faced any performance issue.
I installed Hadoop-0.20.2(single node) and configured it on Linux(Centos).I installed Eclipse and added Eclipse-plugin for Hadoop. I put dataset in /home/Hadoop/input/ali.txt . I am not able to run Wordcount example on Hadoop in Eclipse. When I select the option "to Run on Hadoop", Something doesn't happen.
In addition , when running Wordcount example in Eclipse as java application, encounter with the following error:
Input path does not exist: file:/home/hadoop/workspace/wordcount/home/hadoop/input/ali.txt
help me.
Without the details about which is your $HADOOP_HOME directory and how you configured eclipse before trying to run the program, it is difficult to pin-point the error. However, this is a nice step-by-step guide on creating and testing a Hadoop project using eclipse.
I am the first time for JBPM. When I create object, the project do not know the jar file. Please help me.
The following is my step by step installation.
1.I installed the JBPM plugin in Eclipse Kepler.
2.I extract the jbpm-6.0.1.Final-installer-full.jar in D:
3.I create new projct in Eclipse.
4.After that they do not known jar file.
Please see my image.
Thank in advances.
You need to configure a jBPM runtime (point it to a folder containing the right version of the jBPM libraries you want to use) first.
I would recommend using the installer script to generate a fully preconfigured eclipse environment.
If you want to manually do this:
- unzip the -bin zip from jbpm-installer/lib to a folder
- in eclipse preferences, under jBPM, create a new jBPM runtime and point to the folder you just created
- restart eclipse for the changes to take effect
I have javac version 1.6.0_16 already installed on Windows XP and I'm using both Dr.Java and command prompt to compile and run Java programs.
I downloaded and extracted Checkstyle 5.5 and Findbugs 2.0.1. I'm trying to install Checkstyle and the instructions stated that I need to include checkstyle-5.5-all.jar in the classpath.
My question is, should I place the Checkstyle directory in the lib folder of the jdk1.6.0_16 directory and set the classpath as follows:
C:>set classpath=%C:\Program Files\Java\jdk1.6.0_16\lib\checkstyle-5.5\checkstyle-5.5-all.jar
Is this correct? Should I do the same for Findbugs? Thanks in advance
EDIT: When I added the above path using the environmental variables, and ran checkstyle hello.java, I got the error: 'checkstyle' is not recognized as an internal or external command, operable program or batch file
Maven will solve this problem for you
It sounds like you're just getting started in the world of Java. To that end, I'd suggest that you look into Maven for your build process. Also, you should be using at least JDK1.6.0_33 at the time of writing.
Essentially, Maven will manage the process of running Checkstyle, Findbugs (and you should also consider PMD) via standard plugins against your code. It will also manage the creation of the Javadocs, linked source code and generate a website for your project. Further, Maven promotes a good release process whereby you work against snapshots until ready to share your work to the wider world.
And if I don't use Maven?
Well, just create a /lib folder in your project and stuff your dependencies into it. Over time you will create more and more and these will get intertwined. After a while you will enter JAR Hell and turn to Maven to solve the problem.
We've all been there.
I'm working on an application for my distributed system laboratory course. I have a working ant buildfile that runs multiple targets. My modus operandi currently is to open terminal windows (linux) and run separate ant targets.(with a Logger)
what i would need is the possibility to:
run and debug the project with the ant buildfile in eclipse
open multiple eclipse consoles (or maybe eclipse remote systems - local shells), one per ant target
i found a very good answer/solution here:
https://stackoverflow.com/q/316783
but i didn't get it all together. i read the oracle tut for jar file creation and tried to write a manifest file, i guess creating a java launcher is really basic knowledge,
but it didn't work.
could someone please describe, how to implement the solution by "VonC" in detail (https://stackoverflow.com/q/316783) or share a better/similar/more "simple" one?
You don't need to create your own jar. What the solution is talking about is setting up an Eclipse launcher from an ant target.
A tutorial on how to set it up:
http://individual.utoronto.ca/kia/