project classpath in eclipse - eclipse

I have a question about adding folder/jars/libraries to a project in eclipse.
Let's say i download a folder off the internet which has libraries, do I add it as a folder, external jar or a class folder ?
Either way, I added it and it is now part of the libraries available, but I still get an error in my program saying the class is not available.
I then tried to modify $CLASSPATH to where the folders are sitting and I'm still getting errors.
What am I doing wrong ?

Simply try the following (if your project is a web-application):
Add your libraries (I presume jar files) to your WebContent/WEB-INF/lib folder. What you can do is simply copy the jar (i.e. Ctrl+C) and then past into this Eclipse folder. In this manner, the library will automatically be added to the build-path.
Alternatively, you can follow any of the three-steps outlined in this example:
http://www.wikihow.com/Add-JARs-to-Project-Build-Paths-in-Eclipse-(Java)
I would personally try Method-3 first (which is exactly what I mentioned in the comment provided below).
If this does not work, please try add more specifics to your question. For example, which library did you download (it might help to mention in case you’re missing something we don’t know about). Also, what exactly are the errors you are getting? If you cannot post an image, simply copy what the error is.

After adding all the JARs , try pressing Ctrl + Shift + O (as in Orange). This should re-organize the Imports and try to add any missing ones.
For example, go to excelToText.java and press Ctrl + Shift + O OR Click Source -> Organize Imports like so :
Then when you Save the file ( File -> Save) do you see the Errors disappear ?
See this video to take a look at how this works.

Related

Eclipse Ctrl+Shift+R not showing all files in the project

When i press Ctrl+Shift+R to open the Open Resource Dialog box, the filter box does not show most of the other resource files for example.. jsp, xml etc. it works fine with all the java files.. This is happening for only this particular java project. i have refreshed the project multiple times but still no-go. I have also rebuilt the index for eclipse under workspace/.metadata/.plugins/org.eclipse.jdt.core by deleting the index files but to no avail.
I am using eclipse Kepler version. Any help would be great..
Thanks All. Yes i had closed and opened the project many times. I have also not set any Resource filter exclusions. What i noticed was that opening any of these files for edit would set off an alert saying file was derived and would i like to edit? But on the properties for these file they were not ticked as derived but rather as Archived. So had to manually hunt for the parent folder which was making these files as derived. Also noticed that the Open Resource Dialog box has option for including Resource files "Show Derived Resources"...
This one helped me solve the problem
Eclipse treating all the files in a project as Derived
This is going to sound ridiculous...but maybe this'll help others too: make sure your file search string is correct! You may need to begin it with a wildcard (*).
I lost about 45 minutes on this as the result of user error.
I was looking for some local files named eRCaGuy_PPM_Writer.h and eRCaGuy_PPM_Writer.cpp (from my repo here). So, I pressed Ctrl + Shift + R and searched for ppm_writer, as shown here:
Nothing! It would not find those files! No matter what I did to the files it couldn't seem to find them. I tried all sorts of things. Then, I realized Eclipse doesn't have a fancy fuzzy search like Sublime Text 3, so I simply added an asterisk (*) to the front of the search, and voila! It works perfectly. Since the "PPM_Writer" part of those two file names is NOT at the beginning, I must start the search with a wildcard (*).
Now it works fine, as you can see here:
I've just added a note about this to my personal Eclipse setup and configuration instructions here: https://github.com/ElectricRCAircraftGuy/eRCaGuy_dotfiles/tree/master/eclipse (for my full documentation, see also the PDF and Google Drive links at the top of that page).

How to modify Xcode 4 Project to be Machine independent like Visual Studio or Eclipse behave

I'm very surprised not to be able to open my Xcode project on another mac, I have never that kind of problem with Visual Studio or Eclipse. I have tried this Info.plist file "no such file" error but it's not enough.
I have other errors like MyAppViewController files not found in some folder whereas I checked that the files are actually there.
So how do I modify XCode 4 project so that it can be opened on any mac ?
Update: contrary to what is claimed here Duplicating / importing Xcode projects from one Mac to another copying isn't enough
Update 2: should I be obliged to buy that kind of tools to do so ? http://itunes.apple.com/fr/app/project-duplicator-for-xcode/id467950482?mt=12
Copying the files over is enough, as long as you copy all files over and no files are referenced from your project file using absolute paths.
Note that you don't have to choose to have absolute paths. I'm unsure of the exact details, but I've ended up with absolute paths in projects without doing so explicitly.
For example, here's a project with a missing file:
When I select the missing file, I can see that it's using an absolute path:
At this point, you have two options:
You can click the button in the bottom right of that red box I've drawn to find the file. Make sure you pick the right file; if you pick one with a different name, Xcode will happily replace DetailViewController.m with SomeUnrelatedFile.m and you'll have lost the hint about the original file. After finding it, make sure to pick Location: Relative To Group (usually, that'll be the right choice anyway) to avoid this happening again.
Possibly safer, go back to the original computer. For any file that you know is missing on the destination computer, pick Location: Relative To Group. Then copy everything over again.
I'm not sure if this is what you're after but it might help; I use git on to keep my two laptops in sync with a single project. I don't have any file missing errors and it comes with all those other repository benefits.
You shouldn't need any tools to do this, Xcode projects can be moved, shared between other members of your team and opened on any supported machine.
There must be another problem you have, so you need to post the error.
And when you get it resolved.... using a free remote source control service such as bitbucket, would be good for you to know and get into the practice of using.

Any way to disable syntax checking for a project?

I created a project "Sample Code"... here I just paste sample code... much of it is snippets that won't compile.
Is there some project-specific setting I can make so that Eclipse doesn't try to compile it?
I would prefer not to have the source code littered with red error markers.
Put your code in a non-java project, ie a general project.
Downside: you will have to create package directory structure (unless you can copy and paste from somewhere else).
Upside: it won't try to compile.
MY SOLUTION
ok, this is not an exact solution to my problem... but it is another way to do it and I kinda like it now...
I simply forget about using Eclipse to store the sample java files!
I found a good program CodeBox for Mac to store code snippets and I'm sure there exist such things for Windows, Linux too...
there interesting thing is that when I choose from this program to open the java snippet file (.java) in an external editor (Eclipse), it will open in Eclipse without any Syntax checking... wohoo! no squiggly lines
Because of this, it is not full blown code highlighting... classes and variables same color... but that's ok.. still quite readable. Much more than if it was in Eclipse with syntax highlighting running on it...
So basically, if you want to get rid of these red squiggles... one way to do it is don't keep sample .java (or other language) files in a project in Eclipse... simply keep them in the filesystem or code storage app and open them with Eclipse when you want to view them.
Depending on how you prefer to structure your project:
you could put your java files into a separate folder that is not configured as a source folder. There is an entry in the eclipse help on how to configure your build path.
or you can set exclusion-patterns in the build configuration, so that specific packages or files that follow a pattern you define don't get compiled.
Yet another way to handle your snippets could be to use a Scrapbook page.
Eclipse won't highlight anything in a scrapbook page but you can select code parts inside the page and execute them isolated. That's nice if you're experimenting and don't want to set up a whole class with imports and methods just to see if a specific snippet works as expected.

Easily Open Existing Non-Eclipse Project in Eclipse?

Alright, this has caused me enough grief. The answer may be dead simple, but I need some help.
I figured it would be simple to open an existing project in Eclipse, but I'm having quite a time actually making this work. I don't want to change where it's located. I don't want to pull a bunch of strings to get Eclipse to point to it. I just want to take the project directory from where it is now and open it in Eclipse.
Is there any way to do this?
Not sure that I entirely follow, but here's my general routine for creating projects in Eclipse.
I go to File > New > Project and
pick out what sort of project I
want, and hit Next.
I enter the name I want to use for
the project, and the path where I
want to store it. I never store
stuff in my workspace folder.
For projects with existing code, I
just put the path to the existing
folder, and Eclipse just imports the
code.
Hoping that answers your question, but if not let me know.

Eclipse: Refreshing known types in Java project

If you press Shift+Ctrl+T or choose "Navigate > Open Type..." you get the "Open Type" dialog for quickly navigating to a known class. When you start typing a name only the classes for which the name matches stay visible. That way you can find a class of which you know the name very quick without having to browse through the package explorer tree.
This has been working great for me up until this morning. All of a sudden for a couple of my projects I am only seeing some of the types that exist. Of course I tried the obvious steps of refreshing the projects, cleaning the projects, re-building the projects, rebuilding the projects externally, but all to no avail. It is a bit odd since the types are known in other places. If I add an import statement Eclipse does not complain that it doesn't know the type and I can Ctrl-Click through the types to get to their file. However, the type navigation knows nothing about them.
In the past when InteliJ used to do this to me I would go find its cache files and delete them forcing it to rebuild. Does Eclipse have something similar I might do (I'm an Eclipse newbie)? I am using Eclipse 3.4.2 and I have it configured to not delete files on a clean (because our actual build process puts files into the output directories that I don't want Eclipse mucking with).
Have you tried closing and reopening the project? Only types from open projects are held in memory, and the refresh occurs when you Shift+Ctrl+T for the first time on a newly opened project.
Edit to add: Ctrl+Shift+R also displays the types (along with everything else) but it also supports the Camel-case thing to find the Java types quickly.
Close eclipse and delete any .index files and the savedIndexNames.txt file in workspace/.metadata/.plugins/org.eclipse.jdt.core once eclipse is restarted it will rebuildl the entire index for Ctrl+T
try starting eclipse with the -clean flag, you can add this to your eclipse.ini which can be found in the same directory as you eclispe.exe, or if you start eclipse using a bat or shell script, add it as a startup argument, e.g. eclipse -clean.
The clean will tidy your workspace, and should force eclipse JDT to recalulate types. Ive had issue with .snap files (with seem to be created on dirty shutdowns) that seem to corrupt my workspace until I clean them up, not long ago eclipse lost the Object class!! made for some interesting errors!
I get problems like this often. I tried your solution, noticed it seemed to rebuild its search index, but I still couldn't find any of my classes. Then I took a look at the little green arrow on top right corner of that dialog, and noticed I had a working set selected which belonged to another project. I find it a little dumb that Eclipse doesn't warn you about this or anything, since this can be a very annoying little detail that one tends to forget (me at least ;-)).
Anyways, clicked on "Deselect Working Set" and bam I can find my classes again. Thought I'd add this here since others may make the same mistake.
This worked for me -
Select your project in Package Explorer
Press F5 or Right click and select Refresh
I used the "-clean" as first line in the eclipse.ini (version Juno) and worked like a charm.
I'v tried all the answers and I still had the issue. I then tried this:
I deleted the project (it's a maven project) and re-imported it. This time I made sure i check the "Add Project(s) to working set" checkbox. After that Eclipse was able to find the classes in that project.
The problem must have started because I didn't check this checkbox when i first imported this project.
By the way, I'm using Neon
(Warning: Shameless marketing ahead)
If you like this feature, you would love nWire. nWire allows, among other things, to quickly search not only for types, but for any possible Java element like method or field. It also uses a navigator view which is non-modal. After searching you can see the class associations in a very quick and easy way. Check out the video on our site.