Run Integration tests isolated from each other - maven

Question

is there a way to run integration tests independently?
I got a few selenium tests (reworked in java) in "integration" group, in pre-integration-test phase tomcat runs the webapp and in post-integration-test it shuts down. But the problem is I need the tests to be independent on each other. For example when first test runs, it creates a few posts here and there. I need to reset the webapp (clean everything that the first test did) before running the second test (on a default webapp). All of this needs to be automatic...
Here's my failsafe plugin config from pom.xml.
<plugin>
<groupId>org.apache.maven.plugins</groupId>
<artifactId>maven-failsafe-plugin</artifactId>
<version>2.19</version>
<configuration>
<groups>integration</groups>
</configuration>
<executions>
<execution>
<id>integration-test</id>
<goals>
<goal>integration-test</goal>
</goals>
</execution>
<execution>
<id>verify</id>
<goals>
<goal>verify</goal>
</goals>
</execution>
</executions>
</plugin>
And this is the part with the integration phases and tomcat init...
<plugin>
<groupId>org.apache.tomcat.maven</groupId>
<artifactId>tomcat7-maven-plugin</artifactId>
<version>2.2</version>
<dependencies>
<dependency>
<groupId>com.h2database</groupId>
<artifactId>h2</artifactId>
<version>1.4.190</version>
</dependency>
</dependencies>
<executions>
<execution>
<id>tomcat-run</id>
<goals>
<goal>run</goal>
</goals>
<phase>pre-integration-test</phase>
<configuration>
<webapps>
<webapp>
<groupId>...webapp...</groupId>
<artifactId>...webapp...</artifactId>
<version>${webapp.version}</version>
<type>war</type>
<asWebapp>true</asWebapp>
<contextPath>/</contextPath>
</webapp>
</webapps>
<fork>true</fork>
<port>${tomcat.port}</port>
</configuration>
</execution>
<execution>
<id>tomcat-shutdown</id>
<goals>
<goal>shutdown</goal>
</goals>
<phase>post-integration-test</phase>
</execution>
</executions>
</plugin>

Answer 1

Unfortunately I do not know of any tools out there that simplifies this and a solution will be very specific to the technologies your using (e.g. Tomcat/Jetty/etc., Jersey/Spring/etc., H2/MySQL/etc., etc.) but here are two options:
Do setup/teardown of your web-app from your Java code using a Tomcat Container Java API (instead of using a Maven plugin, e.g. Cargo supports Tomcat and has a Java API (start here although I doubt this will be easy but probably worth it)). This will let you use Before/After methods to set-up and tear-down web-apps on the fly and give you the control you're looking for (you might reuse the same web-container and just reinstall the app, reinitialize the database, etc. or you might tear everything down and start over, your call). This may even allow you to run multiple instances of your web-app at once (assuming you can do this with app) and then run integration tests independently in parallel.
Use the maven plug-in to install multiple instances of your app accessible from different base urls and/or ports.

Answer 2

Technically you'd need to add multiple executions each of which would need to restart app server, deploy the app and run the tests. Which you won't be able to do by standard Maven means. Though you always can write your own plugin.
The issue with your approach though is that it's very complicated (as you already noticed) and very ineffective since you'd need to do multiple deployments. I'd advice to change the approach, here are some suggestions:
Randomize data to isolate tests. In most cases it's possible to prepare and randomize data for tests. E.g. if you create posts on behalf of some user, you can create that user (with random name) for that particular test and create a randomly generated post. This way 2 tests will be isolated from each other. It's not always possible (e.g. you test global configuration of the app), but in 99% of cases it is.
Don't write many System Tests that require real deployment (like those that use Selenium). In most cases it's enough to write Unit tests or Component Tests. E.g. initialize several Spring contexts (or whatever DI you use) and test services/controllers directly. A lot of REST or MVC frameworks have ability to invoke services/controllers directly without real deployments (e.g. Spring MVC has MockMvc). If you still want to deploy the app in tests consider Arquillian instead of Tomcat, but it's still going to be slow. The only case where you need real deployment is when you want to test UI - that requires a full blown app server and browsers.
In general to get testing optimal and isolated you need to build a Test Pyramid where you've got a plenty of unit tests, many component tests and a small number of system tests (which are hard to isolate and take a lot of efforts anyway). See in this article how you can do this in Java apps.