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
Related
Hi i write a Java Swing GUI that includes alot of .jar files.
I have add alot of .jar files to my Buildpath. If now my friend trys to run the programm he got my Buildpath and they are wrong on his pc.
Is there a possible way to set the Buildpath so my friend don't have to set them again?
for example at the moment one buildpath is like this:
home/usr/bonzai/oad/xxx.jar
my programm that is executed is in the folder bonzai. so i want to set the path like this:
./oad/xxx.jar
So the programm knows go into the folder oad, that is in the same folder, then take xxx.jar.
Hope you understand what i want to do :-)
mfg
Christoph
I had this problem with using a project on Windows and Linux.
Go to Window->Preferences->Java->Build Path->Classpath Variables
Click "New", pick a name, like MY_PROJECT, and point to the project folder.
When you include jar files, you do it a different way.
Project Properties->Java Build Path->Libraries (where you add jar files)
To add, click "Add Variable"
Select the MY_PROJECT variable you made and click "Extend". Find the resource and add it to your project.
Now when anyone wants to use your project, they just have to do step 1 and 2. and point the MY_PROJECT classpath variable to where ever the folder is. It can be anywhere. As long as the structure inside is the same, everything works.
This is how I share .project files with GIT. You can clone the project anywhere but everything works.
I'm fresh to Java and cannot get this right.
I've got only a .java file from a Java study book, that represents a Java project. There seems to be no option to input such file from Netbeans interface, that would automatically compile corresponding class and enable project to run.
I've spend a long time to figure this out, copying files manually, changing the automatically created class names and packages, moving this around - but I don't find a solution.
If someone can help - this will be great.
Pawel
It seems the issue was following. .java file should be placed in "src" directory within the Project folder, rather than straight in the Project folder.
So if say "Project" is one's destination folder, then one can:
choose from menu: New Project-Java-Java project from existing resources - indicate path to the ...\Project folder
the next step is to choose "Source Packages Folders" and here the path should lead to ...\Project\src .If the file .java is correctly placed there, the creator will indicate below that .java file is included to the project
If the code is right after finishing the creator and compiling it we get a compiled class Project.class and we can run it :)
Not sure if there is some work around to this in NetBeans, as it's not super intuitive, but I might not have found a better option.
I too was looking for File > "Import File", because there is an "Import Project" option. It appears dragging and dropping the java file into Source Package is just as easy. :)
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'm running a simple Java program from the IntelliJ IDE using the Run->Run menu. It works fine. Now I want to add log4j logging.
I added a resources folder under my project root.
I added a log4j.properties file in that folder.
I changed the code to log something.
What is the right way to tell IntelliJ to include the resources folder in the classpath so the properties file is seen?
With IntelliJ 8 I could guess like a drunk monkey and eventually get it to work. I have 9 now and I am wholly unsuccessful. I've been trying for an hour. How about an "Add to classpath" option somewhere? /fume /vent /rant
Try this:
Go to Project Structure.
Select your module.
Find the folder in the tree on the right and select it.
Click the Sources button above that tree (with the blue folder) to make that folder a sources folder.
Actually, you have at least 2 ways to do it, the first way is described by ColinD, you just configure the "resources" folder as Sources folder in IDEA. If the Resource Patterns contains the extension of your resource, then it will be copied to the output directory when you Make the project and output directory is automatically a classpath of your application.
Another common way is to add the "resources" folder to the classpath directly. Go to Project Structure | Modules | Your Module | Dependencies, click Add, Single-Entry Module Library, specify the path to the "resources" folder.
Yet another solution would be to put the log4j.properties file directly under the Source root of your project (in the default package directory). It's the same as the first way except you don't need to add another Source root in the Module Paths settings, the file will be copied to the output directory on Make.
If you want to test with different log4j configurations, it may be easier to specify a custom configuration file directly in the Run/Debug configuration, VM parameters filed like:
-Dlog4j.configuration=file:/c:/log4j.properties.
I have the same problem and it annoys me tremendously!!
I have always thought I was surposed to do as answer 2. That used to work in Intellij 9 (now using 10).
However I figured out that by adding these line to my maven pom file helps:
<build>
...
<resources>
<resource>
<directory>src/main/resources</directory>
</resource>
</resources>
...
</build>
I spent quite a lot of time figuring out how to do this in Intellij 13x. I apparently never added the properties files to the artifacts that required them, which is a separate step in Intellij. The setup below also works when you have a properties file that is shared by multiple modules.
Go to your project setup (CTRL + ALT + SHIFT + S)
In the list, select the module that you want to add one or more properties files to.
On the right, select the Dependencies tab.
Click the green plus and select "Jars or directories".
Now select the folder that contains the property file(s). (I haven't tried including an individual file)
Intellij will now ask you what the "category" of the selected file is. Choose "classes" (even though they are not).
Now you must add the properties files to the artifact. Intellij will give you the shortcut shown below. It will show errors in the red part at the bottom and a 'red lightbulb' that when clicked shows you an option to add the files to the artifact. You can also go to the 'artifacts' section and add the files to the artifacts manually.
Faced a similar challenge adding files with .ini extensions to the classpath. Found this answer, which is to add it to Preferences -> Compiler -> Resource Patterns -> [...] ;*.ini
If you ever end up with the same problem with Scala and SBT:
Go to Project Structure. The shortcut is (CTRL + ALT + SHIFT + S)
On the far left list, choose Project Settings > Modules
On the module list right of that, select the module of your project name (without the build) and choose the sources tab
In middle, expand the folder that the root of your project for me that's /home/<username>/IdeaProjects/<projectName>
Look at the Content Root section on the right side, the red paths are directories that you haven't made. You'll want to put the properties file in a Resources directory. So I created src/main/resources and put log4j.properties in it. I believe you can also modify the Content Root to put it wherever you want (I didn't do this).
I ran my code with a SBT configuration and it found my log4j.properties file.
For those of you who migrate from Eclipse to IntelliJ or the other way around here is a tip when working with property files or other resource files.
Its maddening (cost my a whole evening to find out) but both IDE's work quite different when it comes to looking for resource/propertty files when you want to run locally from your IDE or during debugging. (Packaging to a .jar is also quite different, but thats documented better.)
Suppose you have a relative path referral like this in your code:
new FileInputStream("xxxx.properties");
(which is convenient if you work with env specific .properties files which you don't want to package along with your JAR)
INTELLIJ
(I use 13.1 , but could be valid for more versions)
The file xxxx.properties needs to be at the PARENT dir of the project ROOT in order to be picked up at runtime like this in IntelliJ. (The project ROOT is where the /src folder resides in)
ECLIPSE
Eclipse is just happy when the xxxx.properties file is at the project ROOT itself.
So IntelliJ expects .properties file to be 1 level higher then Eclipse when it is referenced like this !!
This also affects the way you have to execute your code when you have this same line of code ( new FileInputStream("xxxx.properties"); ) in your exported .jar.
When you want to be agile and don't want to package the .properties file with your jar you'll have to execute the jar like below in order to reference the .properties file correctly from the command line:
INTELLIJ EXPORTED JAR
java -cp "/path/to_properties_file/:/path/to_jar/some.jar" com.bla.blabla.ClassContainingMainMethod
ECLIPSE EXPORTED JAR
java -jar some.jar
where the Eclipse exported executable jar will just expect the referenced .properties file to be on the same location as where the .jar file is
Right-click on your directory and from Mark directory as select Resources root as below:
Perhaps this is a bit off-topic, seeing as the question has already been answered, but I have experienced a similar problem. In my case only some of the unit test resources were copied to the output folder upon compilation. My persistence.xml in the META-INF folder got copied but nothing else.
In the end I "solved" the problem by renaming the problematic files, rebuiling the project and then changing the file names back to the original ones. Do not ask me why this worked but it did. My best guess is that, somehow, my IntelliJ project had gotten a bit out of sync with the file system and the renaming operation triggered some kind of internal "resource rescan".
This is one of the dumb mistakes I've done. I spent a lot of time trying to debug this problem and tried all the responses posted above, but in the end, it was one of my many dumb mistakes.
I was using org.apache.logging.log4j.Logger (:fml:) whereas I should have used org.apache.log4j.Logger. Using this correct logger saved my evening.
I had a similar problem with a log4j.xml file for a unit test, did all of the above. But figured out it was because I was only re-running a failed test....if I re-run the entire test class the correct file is picked up. This is under Intelli-j 9.0.4
Is it possible in Eclipse to create a separate Folder in a package? When select "new --> folder", my eclipse version always creates a package. But i want the new folder to be in the old package.
How can this be achieved?
Thanks in advance...
Patrick
What you might want to do, if you aren't putting code in that folder, is remove the folder from the build path. Right-click on the offending folder in eclipse and choose 'exclude from build path.'
Or, you may want a different effect:
Right click on your project and choose add new source folder.
Then in that folder, add the correct package folder structure.
You can have files in the same package located in different folders.
You need to exclude the folder from the source path
In a source folder, all 'new' folders will be considered a new package. It's part of the Java spec that makes all folders from a root to be part of the package structure.
As others have said, this is standard java behaviour and shouldn't really be worked around.
You are probably better off creating another folder outside of the source folder.
However there is a way to do it in Eclipse, be warned that this might come back to haunt you if you later try to build outside Eclipse as other tools won't honour these settings.
You can exclude a folder from the source path by opening the project properties.
Selecting Java Build Path->Source
Select the appropriate source folder and select the Excluded: child item
Hit the Edit... button.
Select the Add button next to the Exclusion patterns: pane
Add your folder and Finish/OK back to the editor.
The matching resources will now be excluded from compilation within Eclipse. It will still appear as a package in the editor though.
You want to create a new child package (bar) of the existing package. (com.foo)
Select new package and name it "com.foo.bar". Eclipse will correctly place it under com.foo.
FYI: Folders under any "source" folder are shown as packages. There is no physical difference except that they appear on the build path. As shown elsewhere you can exclude them but it's easier to just not put them under /src/... to begin with.