Why can't android find com.google.gson.Gson

I'm trying to use GSON in my project, but my application is crashing, with logcat saying that com.google.gson.Gson ca开发者_高级运维nnot be found. I've put import com.google.gson.Gson on my class files, I have gson in my package explorer, and added it by Right click -> build path -> add libraries. It also shows up in Project->properties->java build path->libraries tab->gson. What have I done wrong?

What worked for me: Check the checkbox next to the lib (gson-2.0.jar) in: 'Project Properties' -> 'Java Build Path' -> 'Order and Export' tab. Then do a clean/build.

This adds the exported=true attribute to the classpath entry

<classpathentry exported="true" kind="lib" path="libs/gson-2.0.jar"/>

Have you put the jar file in the libs folder of the project? If not , try moving it there, creating the folder if required. Should be at the same level as the src folder.

I had a similar issue trying to get an app built and that solved it.

I'm using IntelliJ, not eclipse but here is how I did it:

1. Download the source files from https://google-gson.googlecode.com/files/google-gson-2.2.4-release.zip

2. Unpack them

3. Copy them into the "libs" folder of your project. I did this manually by using the terminal but you can do it by going in your project folder located in your computer. Your Project_Name >app >Libs [paste them here]

4. Go to your editor (IntelliJ in my case) You should see the the following 3 files in the libs folder of the project structure:

   • gson-2.2.4.jar
   
   
   • gson-2.2.4-javadoc.jar
   
   
   • gson-2.2.4-sources.jar
   
   

5. Open your build.gradle file and insert the following line in the dependencies section:
   compile files('libs/gson-2.2.4.jar', 'libs/gson-2.2.4-javadoc.jar', 'libs/gson-2.2.4-javadoc.jar')

6. Right click on each of the source files and select "Add as Library..."

7. Use the following options:
   

   • Name: name of the jar file
   
   
   • Level: Project Library
   
   
   • Add to Module: select project your adding to
   
   

8. Rebuild project Build > Rebuild project
   

9. Import and use it!

   import com.google.gson.Gson;
   

I have observed today that it doesn't like when you add your library. The solution that worked for me was to add it as an external jar only. I have observed it by doing the steps described by author of this post i.e. Properties -> Java Build Path -> Libraries -> Add External JARs and point to the downloaded gson library.

I ran into the same issue (when installed SDK 17) ...

The solution is, that you just put the pure jar files into the "libs" folder (without subfolders). You also don't need to declare them, android wil find them itself. You may need to do a Project > Clean

I had similar problem, but I guess my requirement was more complicated as the GSON libarary was used by an Android Library Project that my main Android project depended on. I have tried both approaches above but none of them worked for me. If I add the GSON jar file directly to the main Android project it works, but that is not what I wanted.

With a bit of investigation I have realised that the GSON jar does not use any dependencies (third party libraries) itself. So my solution was to copy the source file of the GSON project to my Android Library project's src filder and it worked like a charm. so you can use the Source code rather then the binary code. The source code is part of the download in a jar file, just unzip it.

i'm sure you have copied the jar into "libs", and also added property> Java Build Path >(tab) Libraries, right?

my issue was stupid... please check other than Gson jar, if you have two stuffs at least in above tab:

1. android x.x
2. Android Dependencies (especially this one, i missed this, eclipse show me an error of "could not find class com.google.gson.xx" )

simply do a project copy will solve this problem...

Do not edit .classpath file directly or even put files into lib folders out of Eclipse. Instead use the Java Build Path->Order and Export tab to select libraries to be exported in the final deployment unit (eg war/apk) To be on safer side, do a Project->Clean after you change the build path.

I faced the same thing.But the solution was quite easy,just Right-Click on your project->Properies->Libraries->Add external jars->OK and thats it.It solved my problem.hope it will solve yours as well

If Projct Properties -> Java build path -> Add external jars doesn't work and your project is a web project, try adding the gson jar directly to the server lib folder. Example: for apache Tomcat to apache-tomcat/lib.

I have been trying the same thing and read so many answers and tried so many things but to not vial, but i solved this problem by doing just one click and its simple.

1) Add your .jar file in libs folder make sure its libs not lib 2) Clean and Build your project you will see that file under libs folder 3) right click the file and go to build path and select add to build path

Run your project it will work fine. Hope this helps

I am using Android Studio I had the same problem I had solve it by select project press f4 from popup click app and in dependencies select file dependency and select the three folders which I had pasted in lib directory