contentstack-android
· The Content Delivery SDK is used to retrieve content from your Contentstack account and deliver it to your web or mobile properties.
Download JD-GUI to open JAR file and explore Java source code file (.class .java)
Click menu "File → Open File..." or just drag-and-drop the JAR file in the JD-GUI window android-3.12.0.jar file.
Once you open a JAR file, all the java classes in the JAR file will be displayed.