Error on @Override annotation with interface implementation

Check if the RequisitionTypeDTO in interface is the same type as RequisitionTypeDTO in implementation (different imports).

If ok then try adding maven-compiler-plugin

<build>
    <plugins>
        <plugin>
            <groupId>org.apache.maven.plugins</groupId>
            <artifactId>maven-compiler-plugin</artifactId>
            <version>2.5.1</version>
            <configuration>
                <source>1.6</source>
                <target>1.6</target>
            </configuration>
        </plugin>
    </plugins>
</build>

and Maven->Update project configuration... from context menu of your project - because that is the way you should set compilation jre.

And of course try mvn clean, in Eclipse Project->Clean...

If everything fails create new simple project with minimal code and check if there is the same error.

I got this too, and I did have a "Java Builder" set. Further investigation showed that the problem was that my "Compiler Compliance Level" was set to 1.5 rather than 1.6.

Realized no Builder is selected for current project. Selected Java Builder and boom. No more red flags all over the code.