OkHttp上传一个图像应用:DexBug

I'm a beginner on Andriod. I am using OkHttp to Upload an image by post method. So i added okio-1.6.0 jar file to my libs folder and following are my code i keep getting app:DexBug when I run my app. I tried right click the jar and add it to library and made sure compile files('libs/okio-1.6.0.jar') is in my gradle I'm a beginner on Andriod. I am using OkHttp to