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Android Studio not working after Reinstall

I've been having some struggles with building my app after Reinstalling Android Studio. The cues I've gotten have been related to either Java location or installation. With the jre already installed it seems more likely not to be an issue with JAVA.
I've tried importing my project, copy and pasting from .txt files, reinstalling java, redefining java PATH, changing build dependencies, downloading command line sdk manager to build outside of the ide, erasing build caches, and I also let Android Studio rewrite properties.profile when importing Android Studio Project.
Another strange thing, when I create a directory in the project structure it shows up when the ide is initiating before gradle builds. After gradle builds the folder is no longer visible.
EDIT
error: package R does not exist
error: cannot find symbol class appcompat
UPDATE
This seems like a common problem. I've tried to follow most of the current questions on java incompatiblity but still haven't come up with a work around. I downloaded oracle's jdk (unnecessarily) and pointed the studio project at it. Created a shortcut using the jdk java.exe and placed it in Studio core, added java to the PATH which allowed gradlew build in the terminal to initiate but not complete. What are the next steps?
UPDATE
Just in case somebody else stumbles onto this. This post and also this one got me there.
The fix ended up being an import of the .R file. com.example.android.recyclerview.R Hope it can help

Correct Java dependencies installed for eclipse ADT development

I have eclipse and the ADT bundle correctly installed on my home PC, and tried to install it on my laptop so I can work on my projects on the go. However, I either didn't set the java paths correctly, or installed them in the wrong place, because I can't get a default project to load without errors.
I have correctly:
-Installed the ADT bundle and launched eclipse without errors
-Created a workspace
-Correctly Installed both the jre8 and jdk1.8.0_05 in the location C:\Program Files\Java
I am very new to Android development, and I feel like I was lucky to set up the Java dependencies correctly on my home PC, no such luck this time from what the error look like...
However, when I try to make a basic "Hello world" project, I immediately get the following error:
The container 'Android Dependencies' references non existing library 'C:\Users\userName\workspace\appcompat_v7_3\bin\appcompat_v7_3.jar'
I have tried adding the library, by checking build configurations, but I don't understand fully whats going on to correctly solve the problem. Here is my workspace:
And lastly, I tried checking the build configurations to see that the libraries are, in fact, missing. Or something like that. I am not sure if I should just try to reinstall java and the jdk.
Build configuration:
Anyway, I'm not sure what I deleted, misplaced, uninstalled, or didn't install, but if anyone could point me to a solution I would be very grateful. If anyone has any other questions on my setup I will try and be as thorough as possible. Thank you!

In my experience I have had issues like this if not running eclipse as Administrator. Make sure that you aren't being blocked here.
EDIT: Please note Chris Stratton's concers regarding running an IDE as Administrator, as seen in the comments below.
EDIT 2: In my more recent experience, I have noticed that if I installed the SDK by copying and pasting the contents of the downloaded, compressed, folder to a destination rather than extracting it first, I would be required to run as Administrator. If this is the case, delete the SDK that you copied out of the compressed folder and simply extract the contents of the downloaded compressed folder. I am running Windows 7 so it is likely that this applies to all Windows 7 and 8 OS's.
In another case, I have also seen issues like this if the JRE is installed second rather than first. In this case, a reinstall of the SDK is probably all that is required.

java.lang.Object cannot be resolved in Eclipse

When I installed the latest installment in Mac OSX - the Mountain Lion - I experienced some problems getting Eclipse to work I also lost most of my Android developer files (but I still have my projects). I suspect this is due to the choice of removing the /Developer and move the XCode and other Apple developer tools (I placed my Android tools here).
I have now installed the latest version of Eclipse and the problem still seems to be around. There are errors in all my projects and I get an error message prompting:
The type java.lang.Object cannot be resolved. It is indirectly referenced
from required .class files
I tried to check the Java class-path both in Eclipse and in my terminal and these seems to be OK. java and javac both run in my terminal and there is a valid path to the java source files in Eclipse (Under Preferences, Java, Installed JREs). That being said I'm not an expert in Eclipse so there may be that I have misunderstood how this problem ought to be solved. Anyone here with similar problems or who know the cure?

Make sure that you have a valid JRE or JDK defined in the Java Build Path of your project. Right-click on your project, select Properties... and then Java Build Path.

I had this problem moving a Maven project from Eclipse to RAD. I had a JSP file that worked in Tomcat and JBoss, but threw a NullPointerException in WebSphere on the form definition during the compile.
Anyway, after transforming the Maven project into an Ant project (mvn ant:ant), I imported the Ant project into RAD and got this error. The fix:
Open the Java Build Path, selecting the Libraries tab.
Find the JRE System Library and remove it.
Add the JRE System Library.
Goofy, but it works. It must reset some property in a file. I don't know if the problem is the older version of Eclipse or RAD.

After updating my Android SDK to make Appcelerator Titanium happy, I started getting "java.lang.Object cannot be resolved" for my Android projects in (non-Titanium) Eclipse.
I updated all dependencies in Eclipse, and the error healed after a restart of Eclipse.

I had that error almost every time I launched Eclipse for the first time; if I close and then re-open Eclipse, the error is gone.
I found this solution useful, though (I've copied here to protect the link, credit goes to the original author):
In Eclipse go to Windows -> Preferences -> Java -> Installed JREs.
Select the currently active JRE/JDK and press the Edit button.
Select the rt.jar and change its position in the list of JRE system libraries (e.g. press the Up button once).
Confirm all changes, clean and rebuild the workspace.
The next time you face the problem reposition the rt.jar again (or reset the order by pressing the Restore Default button).

please select your installed system jre version from java build path.

Try the following and problem will go away
Close the project and reopen it.
Clean the project (It will rebuild the buildpath hence reconfiguring with the JDK libraries)
OR
Delete and Re-import the project and if necessary do the above steps again.

This is an annoying Eclipse Bug which seems to bite now and then. See http://dev-answers.blogspot.de/2009/06/eclipse-build-errors-javalangobject.html for a possible solution, otherwise try the following;
Close the project and reopen it.
Clean the project (It will rebuild the buildpath hence reconfiguring with the JDK libraries)
OR
Delete and Re-import the project and if necessary do the above steps again.
The better cure is to try NetBeans instead of Eclipse

I got this error and what I had to do was remove the JRE from the Window/Preferences/Java/Installed JREs and re-add it. This somehow cleared up eclipse's cache and rebuilt the project successfully. To get rid of the error in the file-editor I also had to close it and open the file once again.

My problem was that I had in Eclipse: Window / Preferences... and then in the tree on the left Java / Installed JREs: C:\Program Files\Java\jre7
I changed to: c:\Program Files (x86)\Java\jre7
It solved my problem.

I had the same issue and none of the above solutions worked for me.
Then I realized than the library (libs) folder was missing in the project. Once i added the libs folder and the corresponding Jar file, the issue was resolved..

If your project specific (or if not applicable, workspace default) JDK/JRE is being referenced correctly and you've just begun to get this issue out of the blue: restart Eclipse.
Unfortunately, "restart Eclipse" is one of the standard troubleshooting steps when a project won't build. Eclipse even has a dedicated entry under the File menu.

I had to add the JDK under the build path. After adding the correct build path it worked.

I just had to restart eclipse, and the error went away. Strange.

I solved this by pointing my eclipse to the jre available in jdk.

This error caused by invalid sdk is pointing in your project.properties file of your project.
project.properties -> target=android-19 . change to version which is installed in your eclipse.The error will be gone.

I had the same issue after moving from JRE7 to JDK7. Finally I had to remove the JRE7 configuration from the Eclipse preferences and then add the following two lines to the eclipse.ini file.
-vm
C:\Program Files\Java\jdk1.7.0_55\bin\javaw.exe

I had this problem, and I understood that Eclipse has automatically imported a core reference, instead of the reference for the project I needed.
Deleted the import, and rearranged it, and everything worked fine.

Same problem facing Me
Project->properties->Android
And select the api level and also go in java build path and check some external jar file path if we already add in it.update the jar file path

On "The type java.lang.Object cannot be resolved. It is indirectly referenced
from required .class files":
I found my project had 2 meta-inf.java files in 2 different directories with the same 'module ' on line one (a copy/paste error).
Once this was corrected, I cleared the meta-inf.java file with the issue, rebuilding it line by line, guided by Eclipse, until I had a working module configuration.

Error launching first test application: Android Packaging Problem?

Conversion to Dalvik format failed: Unable to execute dex:
wrapper was not properly loaded first
[project]
Android Packaging Problem
I've never worked with Java or eclipse before, I'm following this introductory guide and all searches via google return no helpful results. I'm guessing the problem is I have built Android stuff with eclipse properly but I have no idea, I followed this guide to the letter and everything went as it explains it should.
Any ideas what caused this problem, or is it specific to the guide? If so I'll post on their help page.
I have tried doing project -> source -> clean up, but that didn't fix anything.
Edit:
I went to Project -> Android tools -> Dex bytecode and it reported:
DexDump: missing classex.dex for project. Please compile first.
So I guess that's my problem! Not sure how to solve though.

Go to Project -> Clean
It will rebuilt workspace and fix the errors if any.

As I said, I had the same problem so I tried all the different versions and
then I stopped filling in the SDK-version number
and finally it did not complain anymore about the wrapper.
After that it was totally fine to write the SDK-version when I created new projects.
Hope it works out for you too.

Had the same problem (running on Windows 7). I resolved it by running Eclipse with Administrator privileges.

try to run eclipse under administrator permission. Problem may be resolve.
I think you installed the SDK in "Program Files" folder . So for do something inside, must have administrator permission.

One thing that may help is to create a new test Android project.
In Eclipse, select File → New → Android Project.
Set the project name to "Test3", check Android 2.3 for the build target, type "com.example.android.apps.test3" for the package name, and type "Test3Activity" in the "Create Activity:" text box. The form should look like:
Click Finish.
Expand the entry for "Test3" in the Package Explorer. Navigate to res/values/strings.xml. Double click on the entry for strings.xml:
Set the text content of the string element having name "app_name" to "Test3":
Right click on "Test3" in the Package Explorer and select Run As → Android Application. The emulator should open and after a long while, you should see:
If these steps do not work, then you probably have an error in your installation.
Try it out and let me know.

I had the same problem earlier today. Google was largely unhelpful.
I fixed it by removing the project from eclipse, then re-importing it.
According to this bug report the problem is caused by upgrading to version 9 of the SDK.

Had the same HelloWorld problem with Ubuntu 64 Lucid / Eclipse 3.5.2 from Ubuntu repository. Restarting Eclipse did the trick, though I notice it still fusses about API level requirement when HelloWorld is run.

Running it as Administrator has solved this issue for me..

Had the same problem - occurred after I tried downloading Android platform v2.3.3 (was using 3.1 and 3.2 earlier) and it interrupted in the middle - restarted eclipse and cleaned all projects and rebuilt and the problem went away

At what point in this tutorial/guide are you running into this problem and did you make sure to include your package information in each file or ie com.something.somethingelse at the top of your class or classes?
Perhaps a registry error or maybe even a problem with activity implementation.
Please post your code if this did not start you in the right direction.

Here are a few things to check:
Make sure you have the latest version oF Eclipse (Helios)
Make sure that you have the Android SDK plug-in for Eclipse.
Now if you have done that... Make sure that any classes you add (Each screen you view on Android is a class and is called an Activity) are in your androidmanifext.xml file See http://wrenbjor.com/2011/01/12/the-androidmanifest-xml-file/ for help on understanding this process.
otherwise make sure there are no red x's in your code or it wont work.
If you still have problems post some code and we can try to help.

Had the exact same problem the other night. Upgraded to Helios (3.6) and it went away, quite possibly as a side-effect.

Under windows 7, rather than run eclipse as an admin, change the permissions on the eclipse folder so the creator/owner has full control, and do the same with the folder the android SDK is installed into.

I had installed Eclipse using the files provided by Windows' native ZIP extractor. I deleted the files and took them from 7-Zip instead. Now the error is gone. So maybe using another ZIP extraction tool will help.

Recently got this when failing upgrade using adb-manager with eclipse open (win32). As eclipse was open, upgrade failed. Then returning to my project this problem occured.
Was solved by closing eclipse, restart as administrator and cleaned project.

I had the same problem but I resolved it using following steps(using eclipse helios and windows XP ) :-
Right click on eclipse.exe.
click on Run As...
Uncheck the checkbox before "protect my computer from unauthorized activity".
And it is running for me as expected !
hope it will also run for you.

Error: Unable to open class file R.java [duplicate]

This question already has answers here:
Developing for Android in Eclipse: R.java not regenerating
(64 answers)
Closed 9 years ago.
Did a fresh install of Eclipse, JDK and android-sdk.
I am currently receiving this error when creating a new project
[2010-09-26 16:07:56 - Test] ERROR: Unable to open class file C:\workspace\Test\gen\com\example\test\R.java: No such file or directory
What's the reason for this and how do I fix it?
Eclipse Helios 32 bit
java version "1.6.0_21"
Android sdk API 8
P.S. I'm new to Android development.
EDIT: I tried most of your solutions, but nothing worked. So I started using my friend's install of Eclipse Ganymede.

I have had same issue, all what I needed to do, was create project and restart eclipse.
//Edit: Complete collapsing of "Package" tree works as well.

This is a mighty annoying error.
It happens 100% of the time when I create a new android project.
What seems to work for me is to just delete the file (which DOES exist and is accessible by my user), then hit build, and it will regenerate it and stop moaning.
It's clearly a bug as there are too many people getting it simply by filling in the boxes in the new project dialog (like me) without even modifying any code!

Have a look at your console. It is an aapt aborted error. Since aapt is the tool that auto-generates R.java, therefore, R.java was not getting generated.
Since R.java is a auto-generated file that stores information about your drawables you should rebuild your project. Before that have a look at your layout xml files and check them for errors.
Notice that Project -> Build All should be selected. Also try to run your project.

Removing Read Only attribute on Eclipse workspace directory and Project->Clean->Build Project
did the trick for me. I then clicked on the project directory from within Eclipse and did a F5 (Refresh) . R.java was generated in the gen folder.

I had a similar error on the creation of new projects myself. After messing around I tried moving the R.Java file into the same location as my projects java file (the src file). Eclipse then saw I removed the R.Java file from its location and created another and that seemed to clean up the error.....I dont know if it was because eclipse rebuilt the file and then saw it or what but that seemed to work for now.

After creating the Project, Right click the Project Folder within the Project Explorer on the Left Tab of Eclipse.
Click on Source->Format.
The Console will say:
[2010-11-24 11:57:42 - YourProject] R.java was modified manually! Reverting to generated version!
Then you're good to go. Try running your Project and it will compile.

Check your imports. If this has sneaked in, then delete it.
import android.R;

Had a almost identical issue with Eclipse Helios 64 bit on Linux, but I had the "1.6.0" API selected like you. The bizarre thing was I could type;
cat <the path it was moaning about>
in a console it would display correctly.
I created a new AVD which used Android 2.1, the issue magically vanished. Perhaps it's a bug in Android SDK or Eclipse?

Right click on your project name in package explorer. Then click 'Validate'. It will be fine.

Here is how to fix it:
Go to your "workspace" folder and make sure it's not "read-only"

Eclipse Menu > Projects > clean

Had the same issue.I was able to solve it by doing the following:
go to Window/Preferences/Java/Build Path
select 'Folders' and change the output folder to 'gen' (this is where Android looks for the generated java files,but the default in eclipse is 'bin').
restart Eclipse
Windows 7,Eclipse 3.5.2

Configure buildpath.. check android , it worked, of course i followed one of the posts mentioned above window, preferences, java, java build path and selected project,
then created a project, and tried to build same error, then i checked build path and saw android is unchecked, checked it and build again, it works!

I had this exact same problem with no helpful errors. finally, I tried deleting my debug keystore and it worked:
rm ~/.android/debug.keystore
I had seen people mention that, but I figured it wasn't my problem because I wasn't getting any errors relating to the debug keystore. I found the answer here:
"Debug certificate expired" error in Eclipse Android plugins
apparently the debug keystore is only valid for one year.

I would say that once you have created your project and you've mention the R.class error --> just restart the Eclipse IDE and everything will be fine ;)

1.-Open Eclipse
2.-Open Window/Preference
3.-Expand JAVA option
4.-Select Build Path
5.-Check the option "Projec"t and uncheck "folder" options
6.-Click on OK
7.-Restart eclipse IDE
Let's go to code !!

This problem can be solved by merely cleaning and rebuilding the project. How ever there is a link to the latest version of Eclipse for Android.
**Eclipse Java EE IDE for Web Developers.
Build id: 20100218-1602
(c) Copyright Eclipse contributors and others 2005, 2009. All rights reserved.
Visit http://www.eclipse.org/webtools**
Here is a link to Android Tutorial with Eclipse
http://developer.android.com/resources/tutorials/hello-world.html

In mac,
I select Project>Clean
after that, i unchecked Build Automatically
then i run the project and it works :)

Windows 7 64bit, run eclipse as administrator, solved the problem for me.

In my case there was no gen folder after pressing clear...
To solve it, i created a new gen file, then when to Build Path => Configure Path, and pressed ok.
All went smooth after that :-)

Following steps are done as solutions:
1. Collapse the project tree structure
2. Go to the workspace and remove the readonly permission of the workspace.
3. right click "default.properties" and go to properties and uncheck the readonly permission in eclipse.( this is done when the workspace shows build error even though there are no compilation issues)