Fail build if Guava shows up in src/main/java

Signed-off-by: Dave Syer <dsyer@vmware.com>

Author: Dave Syer

examples/examples-release-10/.google

@@ -36,6 +36,7 @@
     <maven.compiler.source>${java.version}</maven.compiler.source>
     <maven.compiler.target>${java.version}</maven.compiler.target>
     <maven-plugin-version>1.0.0</maven-plugin-version>
+    <exec-maven-plugin.version>1.6.0</exec-maven-plugin.version>
     <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
 
     <javax.annotation.version>1.3.2</javax.annotation.version>
@@ -509,5 +510,51 @@ limitations under the License.
         </plugins>
       </build>
     </profile>
+    <profile>
+      <id>imports</id>
+      <activation>
+        <os>
+          <family>!windows</family>
+        </os>
+        <file>
+			<missing>.google</missing>
+        </file>
+      </activation>
+      <build>
+        <plugins>
+          <plugin>
+            <groupId>org.codehaus.mojo</groupId>
+            <artifactId>exec-maven-plugin</artifactId>
+            <version>${exec-maven-plugin.version}</version>
+            <executions>
+              <execution>
+                <id>imports</id>
+                <phase>process-sources</phase>
+                <configuration>
+                  <executable>egrep</executable>
+                  <successCodes>
+                    <successCode>1</successCode>
+                    <successCode>2</successCode>
+                  </successCodes>
+                  <arguments>
+                    <argument>-rm</argument>
+                    <argument>1</argument>
+                    <!-- Forbidden Keywords -->
+                    <argument>^import com.google.common</argument>
+                    <!-- file patterns -->
+                    <argument>--include=*.java</argument>
+                    <!-- search path -->
+                    <argument>${project.build.sourceDirectory}</argument>
+                  </arguments>
+                </configuration>
+                <goals>
+                  <goal>exec</goal>
+                </goals>
+              </execution>
+            </executions>
+          </plugin>
+        </plugins>
+      </build>
+    </profile>
   </profiles>
 </project>