I am using OkHttp 2.0.0 jar in my android application on eclipse. As OkHttp is now dependent on Okio library, I also added Okio 1.0.0 jar in my project.The project compiles fine with no compilation errors but when I run on my android device, it gives me this
In OkHttp 2.0.0 the language level was updated to Java 7.
See Change log here https://github.com/square/okhttp/blob/master/CHANGELOG.md
In order to fix the issue you will need to update to java 7.
Also at this point you may also need change the target sdk to kitkat (API 19), and update your build tools etc in order for android to play nice with java 7
EDIT: I had the same problem when i upgraded to okHttp 2.0.0 and built with ant. Although the build seemed to succeed i got the NoClassDefFoundError. Going through my build logs I had a whole bunch of silent errors
The first came from javac
warning: com/squareup/okhttp/<classname>.class major version 51 is newer than 50, the highest major version supported by this compiler.
and the second from dex
[dx] trouble processing: [dx] bad class file magic (cafebabe) or version (0033.0000) [dx] ...while parsing com/squareup/okhttp/<classname>.class [dx] ...while processing com/squareup/okhttp/<classname>.class