I have the following project structure:
MyProject
--src
--test
--acceptance
--step_definitions
--features
--unit
The other answer suggested modifying your folder structure to have shared folder for integration and acceptance tests, but you can have the original folder structure as well. Also you mentioned in the comment you want to keep all three (including not-mentioned integration tests) separate, which is possible, though hackish.
Since you seem to have test/unit
for unit tests and test/acceptance
for acceptance test, I'm assuming test/integration
for integration tests.
acceptance-test
maven-failsafe-plugin
2.12
test/acceptance
**/*Acceptance.java
**/*IT.java
**/*Test.java
integration-test
verify
org.codehaus.mojo
build-helper-maven-plugin
1.9.1
add-test-source
generate-test-sources
add-test-source
org.apache.maven.plugins
maven-surefire-plugin
2.12
test/unit
org.apache.maven.plugins
maven-failsafe-plugin
2.19.1
test/integration
integration-test
verify
Note though that separation only applies for sources: compiled files will all go to the same folder, and AFAIK that's something you can't change. This means you need to have naming strategy for your tests to separate them from each other.