Develop Reference

How to import OEM Java lib and source into Netbeans?

I have done a reasonable amount of programming in various languages but I am a Java / Netbeans newbie. I have successfully created and run "Hello World" so my Netbeans installation is OK.
I want to write code to control an LED display controller card. I have sample demo code zipped up by the OEM. I am trying to import, run and edit that code. If I can get this running, this will be the starting point of my own code.
The zip files only include library and source files in a directory structure that does not match Netbeans. All of my attempts to import the source and lib files have given fatal errors in Netbeans.
The directory tree has a lib and src branch at the root. The src branch cascades 4 levels to get to the source files.
I figure if I use a different tree structure, I will need to change the import statements in the source file. I'd rather not touch the code until I have it running. I have tried to unzip the project tree directly into the Netbeans directory but that didn't work.

How to import a JAR (Java Archive, the "library" in your case) in Netbeans:
Right click on your project name, in the 'Projects' pane usually located on the left
Click the 'Properties' link from the pop-up menu
Click the 'Libraries' link in the Categories list
Choose 'Add JAR/Folder', browse to your JAR and click OK
If you want Netbeans to create the JAR for the sources you have, do like Stefano says.

You should package the src folder as src.zip with a zip utility and the structure under lib with the java archiver as a jar file.
Now you can define a library in NetBeans and add these files to it (Tools => Libraries => New Library).

For Netbeans to be able to open a project, the folder has to contain some files that Netbeans itself generates when a project is created.
Since you only have src and lib folders available, I think the easiest solution would be to create a new project from Netbeans, so that the creation of those files is automatically managed, and then copying the content of the folders you have in the folders Netbeans will create.
You will also have to tell Netbeans to use those library, and you can do that from you new project's preferences.
Edit
A few more things you can try:
in NB, right click the folder containing the JARs you imported and select "remove", then import them back but selecting the jar files instead of the whole folder;
if you're not already doing so, use the "Clean and build project" button instead of "Build project";
If none of the above solve the issue, try starting from scratch again following these steps:
unzip your OEM files somewhere in your disk;
create a new empty project in NB
copy the files from the src OEM subfolder to src NB project subfolder
in NB, right click Libraries, then add JAR/Folder and select the jar files from the lib OEM subfolder
If this doesn't work either, tell me where I can find the OEM stuff and I'll try it myself :)

No source attachment in Java

I am trying to use an external .jar file in my project. I have put that .jar file in my project's /lib folder, and I have referenced it in the build path. However, when I try to use it in code, I can't get the javadoc for it, nor I can see the actual code from the referenced classes. It says it has no source attachment. What is it meant by source attachment? I do have a javadoc folder that came with it, but when I attach it to my build path, it still reports it could not found the javadoc for the classes. Any ideas on that?
I want to be able to see the javadoc.

The .jar file is the generated packed classes of the java code. Some jars will come with java doc and code and others won't.
For recent Eclipse versions:
right-click the jar in question (in the referenced jars, not the physical jar) and choose Preferences -> Javadoc. Here give a correct location (zip/URL) to the correct javadoc. (Select Validate!)
For older Eclipse versions:
First: Navigate to the jar itself in the Eclipse project explorer (to the left) and try to open aclass of the jar. Then, you will see the warning that it has no source attachment, and a button to attach the source code.
Then, push the button, select "external folder" and then navigate to the folder with source you already have.

hope I got you right:
try to right-click the jar in the references jar tab and go to Preferences -> Javadoc.
choose the right location to the correct javadoc and press "Validate" afterwards

Jar files can be built with or without source code. It's normal for 3rd party applications to produce a binary jar and a source jar, but it isn't required. The message is telling you that it doesn't know where the source code is for the library you are using. It's been a long time since I've done this in eclipse, but there is a way in the project settings to point each library jar to the corresponding source location (which can be a jar, zip file or directory).
Here are a couple of references
Attach the Source in Eclipse of a jar
Attaching the source to a library in eclipse

Attach the Source in Eclipse of a jar

I added a Student.jar into my Build Path in my eclipse like this-
Right click on the project->BuildPath->Configure Build
Path->Libraries->Add External Jars
There is one class named StudentTest in Student.jar file. When I was debugging my code in eclipse, I stepped into that StudentTest class in the Student.jar.
And after that eclipse shows me like this-
The JAR file S:\some_location\Student.jar has no source attachment.
You can attach the source by clicking Attach Source below
Now I am not sure how should I attach the source in my eclipse. And from where? Can anyone provide me step by step what I need to do.
Update:-
I tried unzipping the Student.jar and I got Student folder. And after that I tried pointing the source to Student folder But still I am not able to see the class properly so that I can debug it properly, it shows the same above behavior.

Use Java Source Attacher !
It does what eclipse should do - a right click context menu that says "Attach Java Source.
It automatically downloads the source for you and attaches it. I've only hit a couple libraries it doesn't know about and when that happens it lets you contribute the url back to the community so no one else will have a problem with that library.

Eclipse is showing no source found because there is no source available . Your jar only has the compiled classes.
You need to import the project from jar and add the Project as dependency .
Other option is to go to the
Go to Properties (for the Project) -> Java Build Path -> Libraries , select your jar file and click on the source , there will be option to attach the source and Javadocs.

A .jar file usually only contains the .class files, not the .java files they were compiled from. That's why eclipse is telling you it doesn't know the source code of that class.
"Attaching" the source to a JAR means telling eclipse where the source code can be found. Of course, if you don't know yourself, that feature is of little help. Of course, you could try googling for the source code (or check wherever you got the JAR file from).
That said, you don't necessarily need the source to debug.

This worked for me for Eclipse-Luna:
Right Click on the *.jar in the Referenced Libraries folder under your project, then click on Properties
Use the Java Source Attachment page to point to the Workspace location or the External location to the source code of that jar.

Go back in to where you added the jar. I believe its the libraries tab, I don't have Eclipse open but that sounds right. to the left of the jar file you added there should be an arrow pointing right, click that and 3 or 4 options expand, one of them being the source file of the library. Click on that and click edit(I think you can also double click it) then locate the file or folder on your hard disk, you probably have to click apply or okay and you're good to go, same with javadoc and i think the last one is native libraries. I don't pay much attention when I'm in there anymore if you couldn't tell. That's what you were asking, right?

I Know it is pretty late but it will be helpful for the other user, as we can do Job using three ways... as below 1)1. Atttach your source code using i.e, Right click on the project then properties --> Java build path--> attach your source in the source tab or you can remove jar file and attach the source in the libraries tab
2. Using eclipse source Analyzer In the eclipse market you can download the plugin java source analyzer which is used to attach the open source jar file's source code. we can achieve it after installing the plugin, by right click on the open source jar and select the attach source option.
3. Using Jadclipse in eclipse you can do it last not the least, you can achieve the decompile your code using this plugin. it is similar way you can download the plugin from the eclipse market place and install in your eclipse.
in jadclipse view you can see your .class file to decomplile source format note here you cannot see the comment and hidden things I think in your scenario you can use the option one and option three, I prefer option three only if i want to the source code not for the debug the code. else i ll code the option 1, as i have the source already available with.

Simply import the package of the required source class in your code from jar.
You can find jar's sub packages in
Eclipse -- YourProject --> Referenced libraries --> yourJars --> Packages --> Clases
Like-- I was troubling with the mysql connector jar issue
"the source attachment does not contain the source"
by giving the path of source folder it display this statement
The source attachment does not contain the source for the file StatementImpl.class
Then I just import the package of mysql connector jar which contain the required class:
import com.mysql.jdbc.*;
Then program is working fine.

I faced the same issue and solved using the below steps. Go to Windows->preferences->Editors->File Associations
Here click on Add
then type .class
click on OK
again click on Add
then type .classwithoughtsource
click on OK
Now you will be able to see JadClipse option under Java section in Windows->Preferences
Please provide the path of jad.exe file as shown below.
Path for Decompiler-C:\Users\ahr\Documents\eclipse-jee-galileo-SR2-win32\jad.exe
Directory for temporary Files-C:\Users\ahr.net.sf.jadclipse
click on Apply
Now you should be able to see the classfiles in proper format.

It is quite possible, just go to the jar in the Build Path and choose to attach a source just like follow.

Download JDEclipse from http://java-decompiler.github.io/
Follow the installation steps
If you still didn't find the source, right click on the jar file and select "Attach Library Source" option from the project folder, as you can see below.

I am using project is not Spring or spring boot based application.
I have multiple subprojects and they are nested one within another.
The answers shown here supports on first level of subproject.
If I added another sub project for source code attachement, it is not allowing me saying folder already exists error.
Looks like eclipse is out dated IDE. I am using the latest version of Eclipse version 2015-2019.
It is killing all my time.
My intension is run the application in debug mode navigate through the sub projects which are added as external dependencies (non modifiable).

I have faced same problem and resolved it by using following scenario.
First we have to determine which jar file's source code we want along with version number. For Example "Spring Core" » "4.0.6.RELEASE"
open https://mvnrepository.com/ and search file with name "Spring Core" » "4.0.6.RELEASE".
Now Maven repository will show the the details of that jar file.
In that details there is one option "View All" just click on that.
Then we will navigate to URL "https://repo1.maven.org/maven2/org/springframework/spring-core/4.0.6.RELEASE/".
there so many options so select and download "spring-core-4.0.6.RELEASE-sources.jar" in our our system and attach same jar file as a source attachment in eclipse.

Try removing the breakpoints. :)

How do you "install" Simple in eclipse?

How do I use simple in eclipse?
Do I add it to the JDK?
http://simple.sourceforge.net
The web site seem to have allot of info on using the methods but little on setting up the library.
I have used C and C++ to set up external libraries before but the Java set up confuses me.
Thank you!

In java world, in order to be able to use third party libraries, what you need to do is to add them to your project/application's CLASSPATH. In case of Simple, its library file is simple-xml-2.4.1.jar that is located inside a folder "jar" within the simple-xml-2.4.1.zip that you would download from Sourceforge.
Download and unzip the
simple-xml-2.4.1 Archive. (ZIP file).
Note that it has a Jar folder that
contains simple-xml-2.4.1.jar - that
is the library eclipse and other IDES
would use to set up the CLASSPATH
Goto your project in project
explorer.
Right-click on the project name and
select "Properties". Alternately, you
can click on the project name and
type "Alt+Enter". A window will
pop-up.
In the window, select "Java Build
Path". You will see several tabs,
including "Source", "Projects" and
"Libraries".
To add simple-xml-2.4.1.jar to your
project, click on the "Libraries"
tab. From there, you can add either
internal jars or external jars. The
"Add External Jar" would be to add a
jar that's on your computer somewhere
. So choose that button, browse to
where simple-xml-2.4.1.jar is located
and make sure to add it to your build
path

How do I include .class files in my project in Eclipse? (Java)

Hey all. I am working on a project for school where we are given the .class file but not the source to include in our code. I am using Eclipse, and I want to include the file in my project so I can instantiate objects from it and use it. The file is TokenizerImpl.class, and I want to use it like this: TokenizerImpl tokenizer = new TokenizerImpl(foo);
I put the file in my project folder, and Eclipse says that "TokenizeImpl cannot be resolved as a type", which I assume means it cannot find the class or source. I tried putting it in the "bin" folder of the project and got the same error. Google search and SO search didn't seem to answer this, so I will give it a shot. How do I do this, oh wise ones?
Edit: Oh dear, I found the problem was something else entirely. These solutions worked fine, but I just forgot to create the Tokenizer interface that TokenizerImpl implements. Doh. Thanks for all your help though, I did learn a lot about eclipse.

You can add a directory containing the class files to the Eclipse project, only if it is inside one of your Eclipse projects, either in a generated directory or in one you have created.
This can be done by adding the class folder to the Java build path of the application. You can set this in the Project properties, by visiting Java Build Path -> Libraries -> Add Class Folder. Keep in mind, that you will have to specify the root folder containing the class files in their packages.
Therefore, if you wish to have the compiler access com.stackoverflow.Example.class present in the classes directory under project A (but not in the build path of project A), then you should add 'classes' as a class folder, and not classes/com/stackoverflow as a class folder.

Project -> Properties -> Java Build Path -> Libraries -> Add External Class Folder
The folder must contain a package hierarchy, i.e. if your class is really foo.bar.TokenizerImpl it must be in the subdirectory foo/bar.

You could also JAR the class files that you want to add and add the JAR file to the build dependencies. To me this is the cleanest solution. Internally the JAR file has to have the correct directory structure, of course.
Right click into your project and select Java Build Path to add new dependencies.
Copying it into the bin folder won't work very well because it is meant to hold the result of compiled sources. As soon as you clean anything the file will be gone.

or put everything into a jar file and add this as an external jar.

Other people have now given better answers. This "answer" was mainly to get information from the OP because the original question didn't really tell us, fully, what had been tried. There are now two answers that truly answer the question in a long-term way.
My original answer is left below for context.
Did you copy it to the bin folder within Eclipse or outside Eclipse? If you did this outside Eclipse then you have to right click on the "bin" folder and select "refresh" for Eclipse to see the new file.
A *.class file in the appropriate folder (depending on its package) under the bin directory should do it.

zip the class folder.
Highlight project name, click "Project" in the top toolbar, click "Properties", click "Libraries" tab, click "Add External jars", add the zipped file