Is there a plugin in eclipse where can type in a quick java code sample and run it? I remember seeing something like this a long time ago.
You can use the Scrapbook:
You need to explicitly reference all class files using a full package name, but you can get around this by importing all the libraries (including the JRE libraries) you need onto the runtime classpath.
Related
I am getting started with Jena and semantic technologies (I am taking a class on the topic). The lecturer recommends using Eclipse as IDE, but I would like to use Visual Studio Code. How can I import apache.jena? I would like to get information/error messages as you would with any other library.
I have had amongst VSCode's extensions, but did not find any support.
I include "import org.apache.jena.rdf.model.;" and get a "not found" error when I try to compile - unless I also include "-cp "/path/to/apacha/jena/on/my/computer/:." when compiling and running the program.
The goal is to be able to compile and run without having to include a path to the library and if possible, for VSCode to have an understand of the library (giving me warnings, suggestions, error messages osv.)
Use Java in VSCODE. You need to install the Extension Pack for Java, and the documentation contains more information.
Use VSCode to open the Java project folder, expand the project structure and display it on the JAVA PROJECTS panel.
Click the plus icon next to Referenced Libraries to add a .jar file reference. Of course you need to download the Jena library on your machine first.
Or use the following configuration in setting to add reference.
"java.project.referencedLibraries": [
"/path/to/jena/lib/*.jar"
]
I need to develop a Tool for checking certain Java Code conventions for all the java classes present in a Java Project.
For one of the rules(i.e;Checking the Class Name Convention)I need to get all the Class Names given the Folder Name.Instead of parsing it line by line,can anybody suggest me a better way to do the same.
NOTE 1: Reflection is not an option because it doesn't work across java projects.I can not use build path as well since there would be many projects at run time for which i need to check the code conventions.
NOTE 2: Currently,I ma using eclipse IDE to build this,but in run time I am not even sure whether they would be using only eclipse IDE.Hence,when you suggest any eclipse plugin ,please bear this in mind.
Thanks in advance:)
So i have tried to find an answer but didn't manage to do it yet. What I'm trying to do is to write a Java code for example in Atom editor, and compile it on Atom itself, without the need of an integrated development environment. Same goes with adding classes to a project.
Is that possible?
Yes. That is how they wrote the first Integrated Development Environments. Although the compilation step is typically performed externally from the editor, if the editor can execute external programs then you can "integrate" compilation. Adding "classes" is a little more involved, in that it requires your "editor" to understand the packaging and structure of the files composing the classes - at that point you have an integrated development environment.
Yes it's possible with atom package build. To install the package Edit-->Preferences-->Install and type build and hit Enter. Then you should configure your custom build command as mentioned in official package website. You may just fill cmd: javac in yml file for example
You need to install a package that will compile. Atom is a hackable text editor but not really an IDE as you pointed out. That said there are a lot of packages for compiling and for working with java.
You can look at Build Tools Package for compiling. It looks like it will work for Java but there are many compilers in the package list.
I would search on their package site for the keyword "Java" to see what java packages you might want to use. Then do another search for "Compile" to see what compiler you might want to use if the build tool above doesn't work for you. You can search atom packages at https://atom.io/packages.
In Eclipse, using the CCW plug-in, I want to load a clojure file into a REPL. The problem is that I have an import statement for one of my own java classes, but apparently it is not in my classpath.
(ns my-clj-ns
(:import [alg.gen Enumerator]))
Do I have to make jars out of every class that I want use/test in a Clojure REPL?
Currently, trying to load my clj into a REPL results in an error:
"Load file in Clojure REPL" did not complete normally. Please see the log for more information.
java.lang.NullPointerException
Any help would be greatly appreciated.
You can let leiningen compile these for you using,
:javac-options {:destdir "classes/"}
:java-source-path "src/main/java" ; location of Java source
options or manually compile them and move the class files to the classes/ directory. No need to create a jar.
When you're in the ccw repl, you can hit alt-e to see the stack trace. If you're getting a NullPointerException, I don't think its a classpath issue.
Your code looks fine to me.
I suspect the issue is with your Eclipse Java Build Path, which determines what Eclipse includes in the classpath for your application.
In particular, if your Java class is in a separate project, you will need to either add that project to the build path (right click on project / Properties / Java Build Path / Projects) or package it as a jar.
When you start to have more sophisticated build requirements, you may also want to start looking at Maven to handle this kind of thing for you. Maven is a pain to learn / set up in the first place but it pays of in the long run.
Leiningen is also a great tool to use but I personally don't use it for the following reasons:
It is great on the command line, but doesn't integrate so nicely with an Eclipse workflow
Maven is more widely used and better supported in the Java world
There is really nice guide if you want to learn how to do this.
https://github.com/technomancy/leiningen/blob/master/doc/MIXED_PROJECTS.md
But in gist, have a project definition like the following for Java source code.
(defproject megacorp/superservice "1.0.0-SNAPSHOT"
:description "A Clojure project with a little bit of Java sprinkled here and there"
:source-paths ["src/clojure"]
:java-source-paths ["src/java"])
I want my Java application to make a growl notification. My IDEs are Eclipse and Netbeans, and I am trying to implement a library in either (so far it worked it neither). How can I just add the library to my project and then reference the classes from within my own classes? Moreover, where can I find an appropriate library?
Thanks in advance!
EDIT: Ok, now I have somehow managed to implement the library ^^ However: the following command fails:
System.loadLibrary("growl");
It returns following error:
Message: no growl in java.library.path
How can I fix this?
About an appropriate library you should just google it. I found this one (that is tested on 10.5 so maybe it will need some tweaks): http://www.cocoaforge.com/viewtopic.php?f=6&t=17320
To add the library to your project in Eclipse copy it into the project folder (this is not necessary, you could just copy it wherever you want, also in extension folder of the JDK) and then add it through the project settings:
open project properties by right clicking the project and choosing Properties
go to Java Build Path option
go to Libraries and add it
It's possible to use AppleScript script engine in Java 6 on OS X to communicate with Growl. Here's a blog post describing how to do it.
You can use the network binding like in https://github.com/chamerling/JavaGrowl or https://github.com/aerofs/growljavabindings
Maybe this can help you.
If your classes are packaged in a JAR file, just like a 3rd party library, you should be able to put it in your project /lib directory and add it to the CLASSPATH using the IDE. That should be all you have to do (if I understand your question correctly).