Add .jar dependency to Java Library Module Android Studio

Question

I am trying to create a Java library in Android Studio. I want to use functionality of another Java library (third party available as a .jar) in it. So I placed the library in libs folder of my java library project and added the following code in build.gradle file:

apply plugin: 'java-library'
dependencies { 
    implementation files('libs/libraryname.jar')
}

The .jar reference was added successfully and I can use the library methods in my code. My project also compiles successfully and I am able to generate a .jar file of my own java library project.

However, when I am using the generated .jar file in another project and try to access the methods of third party library, I get the following exception:

java.lang.ClassNotFoundException: Didn't find class "com.packagename.classname" on path: DexPathList[[zip file "/data/app/com.packagename-1/base.apk"],nativeLibraryDirectories=[/vendor/lib64, /system/lib64]]

What I have tried

I have tried multiple solutions provided here and here but none of them works.

I have tried to clean and re-build the project and .jar files as well but that doesn't help as well.

I have added the .jar dependency as a module before referring it in my project but it still generates the same error.

Note:

I am using Android Studio 3.1.4

Can you iport it from setting? Can I tell you about this way? — Alesandro Giordano, Nov 08 '18 at 11:16
@AlesandroGiordano If you are talking about Settings > Project Structure, then i have already tried it. — Jordan, Nov 08 '18 at 12:02
Yes I told about Project Structure -> Libraries -> Dependencies or also you can import it in other way.. I'll answer your question with this method — Alesandro Giordano, Nov 08 '18 at 13:13
Are your class public? are you importing the library in a second android studio project? Did you have imported the libray in the same way that you have import the first library? — Alesandro Giordano, Nov 09 '18 at 14:29
yes classes are public. Yes I am importing the library in a second project in the same way as i did in the first library — Jordan, Nov 10 '18 at 15:02
Ok tomorrow I will ask you more details if you haven’t find a soluction — Alesandro Giordano, Nov 11 '18 at 16:59

score 0 · Answer 1 · answered Nov 08 '18 at 13:16

0

Copy .jar in your libs project folder: change the navigator to project view, than you are able to see libs directory. Right click on your jar folder inside your project and select add as library, this will automatically import the library on your gradle dependencies

answered Nov 08 '18 at 13:16

Alesandro Giordano

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In android studio 3.1.4 add as a library option is not shown when i right click the .jar file. – Jordan Nov 09 '18 at 09:44
Probably is already added in project,, can you check on your project Structure -> libraries if the library is present? – Alesandro Giordano Nov 09 '18 at 10:03
Yes it is present. – Jordan Nov 09 '18 at 10:30
So the problem that you have is not in importing the library – Alesandro Giordano Nov 09 '18 at 10:48
can you check if the library that you are importing correctly? try to decompile it t see his method reference – Alesandro Giordano Nov 09 '18 at 10:49
I am able to call the library methods in my JAVA library code. The issue arises when I compile it and use the generated .jar file in another project. – Jordan Nov 09 '18 at 13:05
Please refer to my question again – Jordan Nov 09 '18 at 13:06

Add .jar dependency to Java Library Module Android Studio

1 Answers1