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
Related
I'm posting this query after doing lots of googling and trying out different options for last few days. Is there an easy way to attach source in Eclipse? is the closest answer I found to my question.
From above post, I tried all solutions but each time Eclipse is opening .class file instead of .java file.
Eclipse Details:
Kepler Service Release 2
Build id:20140224-0627
Please let me know if this is a bug with Eclipse or if I am missing something.
If you are using Maven, try this:
Double click on your project in eclipse -> Maven -> Enable Workspace Resolution
This is most likely because Eclipse actually use the class file for declaring the item you have requested the declaration for, and not the source file you think it should be using.
The typical reason for this is if you have a jar file containing previously compiled classes on your build path before (or instead) of the project containing the source you want. This is very rarely desirable as it can take quite a while to discover that your edits do not take effect.
Examine your build path carefully and ensure it is as you want it to be.
Maven is likely supplying a Classpath Container to your project, and generating entries for the Java Build Path based on the pom.xml contents (the JRE System Library is another example of this). Its entries will not have source attachment unless the container decides it will, which is why the Installed JREs preference page offers to let you set Source Attachments. If the pom.xml has something like that, see if you can use it. If not, see if you can configure the Maven container from its context menu. Otherwise, you may simply be stuck.
I had this same problem: when I pressed F3 or tried to open Declaration (after right click) for any element, it took me to the bytecode .class file.
My solution:
I went to the project in Project Explorer:
right click on project name->Properties
Then in Porject Properties window,
Java Build Path->"Order and Export" tab
There I selected the folder with the .java files (source code), which was below the folder having the .class files -in my case "JRE System Library [java-11-openjdk-amd64]", and pressed 'Top' button on the right frame. Then the folder with source files moved to the top.
Finally, pressed "Apply and Close" button.
That solved my problem forever and ever.
The folder
I installed a plug-in which allows me to download the sources for a maven project.
I'm not by my develop machine right now, but I think it was this:
http://marketplace.eclipse.org/content/m2e-dynamic-sources-lookup#.U8gjGWIaySM
With this, you can select a project an have maven download the sources and make then available when you navigate the code in Eclipse. All without "leaving" Eclipse.
Check into your project modules the Java Build Path, look inside the Source tab and verify if you have "Allow output folders for source folders" checkbox flagged; in this case you just need to uncheck it and you will be able to see again the right source from java files.
This is related to the Call Hierarchy in Eclipse IDE.
If you are in a situation, where you're seeing duplicate methods inside the call hierarchy showing Members calling 'myMethod(...)', double-clicking on one of the listed methods may open the .class file instead of the .java file.
When this happens, the solution is to set the search scope in the call hierarchy to Project instead of Workspace.
After setting the search scope, you won't be seeing duplicate methods listed in the call hierarchy, and double-clicking on the listed methods will only open the .java files.
(Using Eclipse DevStyle Dark Theme)
I'm a complete novice to Java, and I'm stuck in trying to use an external jar library in a Java project I'm working on.
The library is Twitter4J (http://twitter4j.org/), a complex group of files which I can't understand how to include. I'm using Eclipse on Windows. I understood the meaning of CLASSPATH enviroment variable (or well, I think I did), but I can't understand how to link it to the Eclipse enviroment.
This blog post seemed to be what I was looking for: http://jasperpeilee.wordpress.com/2012/01/25/how-to-set-up-twitter4j-quickly-in-your-java-project/
But:
Add twitter4j-core-2.2.5.jar into project for general use.
1) Where should I copy the core file? In the /bin/ folder? Or in a completly unrelated /lib/ folder, as this question in SO stated?
Copy Twitter API property file into your project/bin directory.
2) What is the Twitter API property file?
3) How can I include JavaDoc jar files too? Is it possibile to get them into Elipse?
Any kind of help, even just a link, will be very appreciated!
You probably have a project folder for your Eclipse project. Go ahead and make a lib folder inside of your project folder, in the same directory as src and bin. There's nothing special about the lib folder specifically, it's just a convenient name. Copy the .jar file into your newly created folder. Back in Eclipse, right click your project and click Refresh. The lib folder should pop up, including your JAR! Right click the JAR file and go to Build Path --> Add To Build Path. At this point, any class in the project should be able to use Twitter4J features.
As for the What question, the Twitter API property file contains configuration that is necessary for the Twitter jar to function. The file should probably be located on the classpath of your application.
And the How question, you can attach the javadoc jar file of the Twitter jar to the Twitter jar's classpath entry in Eclipse. Right-click your project and select Properties. Go to the Java Build Path entry and find the Twitter jar under the Libraries tab. If you expand the Twitter jar entry you will see 'JavaDoc location'. You can specify the javadoc jar there.
In Eclipse, right-click your project, select Properties. Now find the entry for Java Build Path and select it. Click the "Libraries" tab if it is not already selected. Click the "Add external JARs..." button. Follow the prompts.
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. :)
I have had problems getting Content Assist in Eclipse to work with Guava. This assist works fine for code which has source I have loaded into projects (such as JFreeChart), but I cannot find source code for Guava. I have tried putting all three jars into the build path (guava-14.0jar, guava-14.0-javadoc.jar, guava-14.0-sources.jar), and have pointed the Javadoc location to a folder on the hard-disk with guava-14.0-javadoc.jar. With any combination of these, I get "Note: This element has neither attached source nor attached Javadoc and hence no Javadoc can be found." from a hover. Any ideas?
In Eclipse, you have to point the Javadoc location to the guava-14.0-javadoc.jar file itself, and not to the folder containing it.
In your project properties, go to Java Build Path, tab Libraries, find the entry for the guava jar and click on the little triangle on the left to unroll the jar options. Click on "Javadoc Location" and chose the "Edit..." button. Then choose "Javadoc in archive" and "External file". Write the jar file path or use the Browse button to find the jar.
You don't need to put the javadoc and the source jar in the build path.
How can I link source to a jar package in eclipse?
I am trying to add the external library ch.ntb.usb.
I added the jar file to my build path, but when I tried to run the application it returned the following error:
The jar file ch.ntb.usb has no source attachment.
I've used JD-GUI to decompile the jar file and the source code is contained.
I doubt that you get that error when you only run the project unless you have an error in your code and eclipse debugger try to show the line of code that cause the exception, anyway you may need source files of a library for debugging purpose, to link source to a jar package in eclipse you can follow these simple steps :
Find the package which you want to add the source under Referenced Libraries in Package Explorer
Right Click on the library
Select Properties
Go under Java Source Attachment
Select the directory or archive where your source is located.
I "Saved all sources" with jd-gui into my build path as ch.ntb.usb.src after unzipping the jar file. Then I set the source attachment of the external library to ch.ntb.usb.src. This fixed the issue.
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
Click right in Package Explorer your Project
Select Properties
Select Android
Scroll down
Under Library click Add
Select the needed Lib and press OK