Cannot find the class file for java.lang.Object - java

I reinstalled my eclipse. and then imported all the projects in the Eclipse, but every project has a common error:
Cannot find the class file for java.lang.Object. at Line 1.
I have checked my Java Path. But not able to sort it out.

Right click on Project--> Properties, Java Build Path.
Check whether you have JRE installed. If installed click on EDIT and check whether its pointing to correct location

Check this if it works:
There is a problem with your java repositories. I guess..:
goto Help>Install New Software> Click on Add Button .
on popup:
Name: ADT
Location:https://dl-ssl.google.com/android/eclipse
Install all the available softwares in the list. This may work.
Have a good day!!!

A quicker way will be
Right Click Project---> Properties--->Build Path--->Add External Jars--> Find your android-xx.Jar e.g android-17.jar
In my case I'm using the adt and it is here
E:\adt-bundle-windows-x86_64-20130219\adt-bundle-windows-x86_64-20130219\sdk\platforms\android-17
Hope it helps

This happened to me when I tried to merge two branches of an Android project using eGit. For some reason my build path basically disappeared (possibly one of the files was untracked).
To get the JRE and android libraries back, I just right-clicked on the project in the project explorer, and hit Android Tools -> Fix Project Properties (these options are only available if you have Android ADT installed).

Try this:
Go to Build Path -> Libraries -> Add Library -> JRE System Library -> Select JRE
I am not sure but you might be missing JRE System Library in your project, this does not happen often but it is possible.

I just had this problem and all I had to do was clean the entire workspace, i.e. all projects in the workspace. The error went away.

I've had this problem after installing a newer version of Google ADT.
The solution, at least running OS X, is to make a copy of your project to a safe location, delete it completely from Eclipse and then import it again using File->Import->General->Existing Projects into Workspace.
FYI
I am Using Google's on OS X Mavericks
Android Developer Tools
Build: v22.2.1-833290
but I am almost sure I have done in the past with previous OSX and ADT versions.

I had this issue too and in my case the issue was that the following line was missing from the .classpath file of the current project:
<classpathentry kind="con" path="org.eclipse.jdt.launching.JRE_CONTAINER"/>
Adding it solved the problem for me.

This error is because one of "Android Private Libraries" is either corrupted or of wrong version.
In my case it was android-support-v4.jar.
I replaced it with one from a working project and it works.

Related

IntelliJ: Cannot resolve symbol 'String' [duplicate]

What are common causes for IntelliJ IDEA not being able to resolve built-in JVM types and methods? For example, when I mouse over String the tooltip says "Cannot resolve symbol 'String'". It's as if IntelliJ has doesn't know where the JVM is.
By the way, I am running OS X 10.6.6. Everything was working fine until I ran the system update this morning.
Most likely JDK configuration is not valid, try to remove and add the JDK again as I've described in the related question here.
First check if you have configured JDK correctly:
Go to File->Project Structure -> SDKs
your JDK home path should be something like this:
/Library/Java/JavaVirtualMachine/jdk.1.7.0_79.jdk/Contents/Home
Hit Apply and then OK
Secondly check if you have provided in path in Library's section
Go to File->Project Structure -> Libraries
Hit the + button
Add the path to your src folder
Hit Apply and then OK
This should fix the problem
I was facing the same problem when import projects into IntelliJ.
for in my case first, check SDK details and check you have configured JDK correctly or not.
Go to File-> Project Structure-> platform Settings-> SDKs
Check your JDK is correct or not.
Next, I Removed project from IntelliJ and delete all IntelliJ and IDE related files and folder from the project folder (.idea, .settings, .classpath, dependency-reduced-pom). Also, delete the target folder and re-import the project.
The above solution worked in my case.
For me, I had to remove the intellij internal sdk and started to use my local sdk. When I started to use the internal, the error was gone.
I tried almost everything but nothing was helping with the ibm jdk 1.8. to fix this issue. then I found an article from https://youtrack.jetbrains.com/issue/IDEA-279214/Cannot-resolve-symbol-String-when-using-IBM-JDK-180 and it worked like charm!!!
so sharing original help credit goes to #Serge Barano. incase anybody needs and not able to able to resolve the issue using previous solutions like me.
according to the article answer is:
IBM JDK has a weird layout and the jar with the String class is in bin directory for some reason:
d:\dev\ibm_sdk80\jre\bin\default\jclSC180\vm.jar
If you add it to the JDK classpath in IntelliJ IDEA, the issue should resolve:
For me, IntelliJ could autocomplete packages, but never seemed to admit there were actual classes at any level of the hierarchy. Neither re-choosing the SDK nor re-creating the project seemed to fix it.
What did fix it was to delete the per-user IDEA directory ( in my case ~/.IntelliJIdea2017.1/) which meant losing all my other customizations... But at least it made the issue go away.
First of all you should try File | Invalidate Caches and if it doesn't help, delete IDEA system directory. Then re-import the Maven project and see if it helps.
For me ,
File -> project structure -> Project Language Level (11) selection worked. Local variable syntax for lambda paramters.
In my case, cloning repo from the remote was the easiest way to solve this issue.

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.

android-support-v4.jar isn't importing correctly in Eclipse

I'm trying to get an app to compile that uses the android-support-v4.jar and the Fragmentation classes it contains, but I keep getting messages whenever I try to compile that there are errors in the code. All of the errors have to do with different Fragmentation classes that are in the .JAR. I have tried ctrl-clicking the project folder and then selecting Android Tools -> Add Compatibility Library and I keep getting this error:
[2011-12-20 11:55:31 - Android Compatibility JAR not found:]
/Applications/eclipse/Eclipse.app/Contents/MacOS/v4/android-support-v4.jar
Why would it be looking for the .JAR in Eclipse's Package Contents? I've gone into the project properties and went to the Java Build Path, and imported the .JAR from the MainActivity/libs folder, that didn't work, and then I tried to import it from my SDK directory, and that didn't work. I've fixed the project properties and cleaned and built it countless times, I've restarted Eclipse, my computer, re-downloaded and installed Eclipse, the Android SDK's and ADT and still nothing. I am completely stumped.
Edit
I've gone through the build path and imported the .JAR from both the MainActivity/libs and my SDK directory. For the hell of it I added the .JAR in the directory that keeps appearing in the errors and that hasn't worked. What's making Eclipse look for it in it's Application Package Contents?
Update
So after tinkering the project contents aren't showing any errors but the MainActivity folder still says that there is one and I still can't compile.
Like nyah:
Revision
So I think the question may be "Why is Eclipse looking for the .JAR in the Eclipse Application's package contents instead of the libs directory of the project or the Android SDK directory that I used to import it as an external .JAR?"
Update #2
I am only getting one error now after tinkering, it's on this method:
#Override
public MenuItem setOnActionExpandListener(OnActionExpandListener onActionExpandListener) {
// Noop
return this;
}
The Quick Fix says that I should delete the #Override annotation but that method must override a super class method.
These are the errors that it shows:
Multiple markers at this line
- The method setOnActionExpandListener(MenuItem.OnActionExpandListener) of type SimpleMenuItem must override a superclass method
- implements android.view.MenuItem.setOnActionExpandListener
Looks like it is looking for jar here :/Applications/eclipse/Eclipse.app/Contents/MacOS/v4/android-support-v4.jar
android-support-v4.jar is found in <sdk>/extras/android/compatibility/v4
Please make sure you add this as an external jar in the java build path
I could solve this problem by
1- delete "android-support-v4.jar" from lib
2- right click on the name of the project choose "Android Tools" and "Add Support Library"
If this is still not solved:
Like already said, in Eclipse go to your Project Properties > Java Build Path > Libs > Add External and get the one from the adk directory.
Also set up Java 1.6 as your default compile version if you already haven't. This should solve the Override Errors you described.
It turns out that my Debug Certificate had expired so I just needed to delete ~/.android/debug.keystore and restart Eclipse and everything worked.
I realize that this question has been answered, but this is a known issue that is supposed to be fixed in the ADT-17 plugin release according to comment 9 here: http://code.google.com/p/android/issues/detail?id=21488
In addition, people who have this problem can copy the compatibility JAR to the location it says it can't find it. Clearly it's looking in the wrong place (since it's checking the Eclipse directory rather than the android-sdk directory), so the simple fix, for now, is simply to put the package where it wants to find it, even though it doesn't belong.
For me it was as simple as copying the v4 directory within C:/android-sdk/extras/android/support/ into the C:/eclipse/ directory.
I had the same problem running in Ubuntu. Go to Tools->Options.
Check Force https://... to http://
Open Android SDK Manager. Check Extras->Android Support Library.
Something similar happened to me. At the top of MainActivity.java I had the next imports giving errors:
import android.support.v4.app.FragmentActivity;
import android.support.v4.app.FragmentManager;
import android.support.v4.app.FragmentTransaction;
In each of the lines on the left they had the light bulb making some suggestions. If you click on it, one of the options will be "Fix project setup". You then will be able to choose between several options for fixing the imports, you should choose the one that specifies the android-support-v4.jar.
Right click on ur project --> select android tools --> select add support library and simply installed the supporting libraries.
Do you try not to do Android Tools -> Add Compatibility Library, and only add the jar in java build path library?.
I use this jar library of this way and it works without any problem.
I had the same problem.
Under the project properties:Java Build Path:Order and Export tab, the box next to android-support-v4.jar wasn't checked. I checked the box, and the error went away.
Another caveat was running Android SDK Manager in Windows 7 without administrator privileges. It would try to install support package, but would always fail, and the actual package never got downloaded to
C:\Program Files (x86)\Android\android-sdk\extras\android\support\v4\android-support-v4.jar
Solution: Make sure that you enter the same API for "Target SDK" and "Compile with" during Android project creation (or in the Manifest file once created).

How to avoid "Refreshing external Folders" in Android development in Eclipse

I am having this annoying problem which takes 10-20 seconds and sometimes more every time my android project is refreshed or rebuilt.
I searched for android forums and also in stackoverflow and but solutions does not make sense. Please give me the solution or link to it.
My android project depends on two external java libs and android libs. Tell me if you need more info.
Earlier I asked this question and it solved the problem by removing 'source attachment'. But I believe it is not a good solution because I need source to be attached with jar. It helps while debugging, code browsing. If source is not attached then, your breakpoint stops there and you can't go in readable source.
Better Solution Needed. Is there a launcher option? which disables when app launched. or build options?
Instead of attaching a source folder to the .jar file, you should zip the source folder and attach the zipped file to the .jar.
See this answer for more info https://stackoverflow.com/a/9699242/637754
The reason for this is that you have attached source with your dependent jars. Just the remove the source from the class path. This how it can be done.
Right click on the project -> Select Build Path -> Configure Build Path.. -> Select Libraries
Select the Source attachment and Remove button will highlight. Press Remove and OK.
I think that should fix your issue.
this helped me so you can try too:
Go to your Workspace root/.metadata/.plugins/org.eclipse.jdt.core/ and remove .org.eclipse.jdt.core.external.folders folder
it contains .project file with links to external folders which takes too long to refresh
You can disable "Refresh on access" option in Window->Preferences->General->Workspace - it have no effect as I think, because even it's turned on you must manually refresh projects if you modify them outside of Eclipse
If anything else fails (my case), install a fresh copy of Eclipse Juno
Go to Help-Install Software, and add this repo:
https://dl-ssl.google.com/android/eclipse/
Check all options and install.
For migration reasons I was trying to install Eclipse on MAC OS Yosemite, since Android Studio is now the official IDE, it is hard to find Eclipse setups with the ADT plugin included. I tried several versions of Eclipse, and JUNO did the work.

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)

Categories