I have managed to make JAVA8 / AWS SDK 1.9.x work with Maven and Eclipse following this remarkable examples pedropaulovc/aws-flow-maven-eclipse-samples and tweaking the pom.xml, including the brave Mircea suggestion and other reworks.
you can find the resulting working pom.xml here
Note that i had to add to the aspectj plugin aspect libraries also the updated flow-build-tools, otherwise, the Activity and Workflow impl version number annotations do not work properly
com.amazonaws
aws-java-sdk-swf-libraries
com.amazonaws
aws-java-sdk-flow-build-tools
Hope this could be helpful!