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.
Related
In a Java project I have a dependency on my own library. I have installed this library in the local repository by running mvn install in the root of the library's directory.
When I updated the library and re-installed it, VS Code couldn't see a newly-added method (everything compiles fine from the command-line).
I've tried Java: Force Java Compilation (full) and that didn't work.
In pom.xml I right-clicked on my library and chose Update Project and that didn't help either.
If it makes any difference, I am running on WSL2 (Ubuntu-20.04) on Windows 10.
Is there any solution short of restarting VS Code (which is a rather cumbersome workaround)?
Executing the Java: Clean Java Language Server Workspace command from the Command Palette (Ctrl+Shift+P) should work.
If you added new dependencies or jars, java language server will build and compile them automatically.
In some rare cases, you may need to execute the above command to let the language server rebuild your dependencies.
Reference: Library Configuration
Background
I am a Maven newbie and I greatly like the fact that Maven knows where to pick up all the JAR files needed for executing a Java program (i.e. the fact that the required JARs need not be specified in the CLASSPATH environment variable since they are all stored in the .m2 repository).
I thought Maven could be the preferred way to invoke Java programs for real world applications but for a previous post of mine the following comment was received:
If you want to execute java programs I would suggest to create self running artifacts instead of using maven to execute a program
This brings me to the following questions:
Questions
Should using Maven as the tool for invoking Java programs be frowned
upon?
If yes (i.e. there are issues in using Maven as the
preferred method for Java program invocation), what are the better
alternatives and why?
Maven is a build tool and was not designed to run programs.
If you want to test your program, your IDE should be enough to start it without any classpath hassle.
If you want give the program to someone else, use the Maven assembly plugin or the Maven shade plugin to bundle the jars with the dependencies. Then you can run it on any computer with Java installed.
We just started using Lombok plugin for Java.
Developers in our company use Eclipse for workspace and we have some clients who get access to part of our source code.
If we use Lombok library, it doesn't get detected in Eclipse until the plugin is manually installed.
It's hard to send a communication to multiple clients and have them mandate the plugin installation.
Is there a way to automatically install a plugin from the project itself, may be with an yes/no question to let the users accept it, that way we don't get accused of sneaking stuff in :)
It is NOT possible to install an Eclipse plugin from the project itself.
It is clearly stated in the Lombok documentation that manual installation is necessary as Lombok is a preprocessor. Lombok needs to be installed to the Eclipse install folder (next to eclipse.ini). https://projectlombok.org/setup/eclipse
And I suppose it would be a security leak (both in Eclipse and your Customer's environment) if you are able to install something into the 'Program Files' folder from your projects without user interaction. However manually copying is feasible and could be a workaround if you are very keen to do so.
Workaround: You might provide an ANT/GRADLE script that will distribute you local copy of the lombok.jar into Eclipse's program folder. And also create a launcher configuration. So you can refer to this launcher step to be executed. Please note that you need to restart eclipse just after lombok installed. But in fact this is what lombok.jar does when running as described in the install guide.
The standard lombok installation is being done manually.
Therefore, I've created an automatic installer.
It's available here: https://github.com/zorik9/lombok-automatic-installer
Right now it supports only eclipse IDE in windows machine.
The idea is to configure once the variables: lombok_version, eclipse_home and workspace_dir (not mandatory)
And based on this configuration, run the installation script on each machine.
For more details, please read the readme.md file.
I have a Java application I've developed in Eclipse. To package it into a .jar, I simply run File->Export->Runnable JAR file with copy jar files into sub folder selected.
For deployment, I turn over the compiled jar file along with my source code and the deployment team packages it up and deploys it to our systems. One of the responsiblities of the deployment team is to verify that the source code that is turned over compiles into the binary that is turned over with it. This is the only Java program the deployment team works with so they don't have Eclipse available to import my source code and validate it against what I provided them. For the time being, they have just been taking my word for it, but that needs to change. They will need to compile the code on their own and make sure it matches what I've given them.
How would they go about doing this? I suppose one option is to get all of them up and running Eclipse, but that seems like an overkill. Is there something they can run outside of Eclipse without having Eclipse installed to generate a jar file that they could validate is the same as what I've provided?
Thank you for any assistance.
First, how can they tell that what you supplied "matches"? That doesn't really make sense.
What they really want to do is to build their own deployment artifacts from your source. They can either set up Eclipse and use that as their build tool, or you and they can agree to use a build tool such as Maven or Gradle. These tools integrate with Eclipse, but they are designed to run stand-alone or as part of a tool like Hudson or Bamboo, which will perform build on a schedule or when a VCS is updated.
A client used Maven and Bamboo, along with the rest of the Atlassian suite, to handle enormous builds based on contributions of more than 100 developers. That included running JUnit tests, test coverage, and code quality tools.
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.