DATAJDBC-220 - Added a Degraph test for inter module dependencies.

The existing test only analysed Spring Data JDBC itself.
The new test also considers packages from commons and treats

    org.springframework.data.x.X

and

    org.springframework.data.jdbc.x.Y

as belonging to the same "sub-module" "x".

src/test/java/org/springframework/data/jdbc/degraph/DependencyTests.java

@@ -14,25 +14,52 @@
  * limitations under the License.
  */
 package org.springframework.data.jdbc.degraph;
-import static de.schauderhaft.degraph.check.JCheck.classpath;
-import static org.junit.Assert.assertThat;
+
+import static de.schauderhaft.degraph.check.JCheck.*;
+import static org.junit.Assert.*;
+
+import de.schauderhaft.degraph.check.JCheck;
+import scala.runtime.AbstractFunction1;
 
 import org.junit.Test;
 
-import de.schauderhaft.degraph.check.JCheck;
-
 /**
+ * Test package dependencies for violations.
+ *
  * @author Jens Schauder
  */
 public class DependencyTests {
 
-	@Test public void test() {
-		assertThat(	classpath()
-				.noJars()
-				.including("org.springframework.data.jdbc.**")
-				.filterClasspath("*target/classes")
-				.printOnFailure("degraph.graphml"), JCheck.violationFree());
+	@Test // DATAJDBC-114
+	public void cycleFree() {
 
+		assertThat( //
+				classpath() //
+						.noJars() //
+						.including("org.springframework.data.jdbc.**") //
+						.filterClasspath("*target/classes") // exclude test code
+						.printOnFailure("degraph.graphml"),
+				JCheck.violationFree());
 	}
 
+	@Test // DATAJDBC-220
+	public void acrossModules() {
+
+		assertThat( //
+				classpath() //
+						// include only Spring Data related classes (for example no JDK code)
+						.including("org.springframework.data.**") //
+						.filterClasspath(new AbstractFunction1<String, Object>() {
+							@Override
+							public Object apply(String s) { //
+								// only the current module + commons
+								return s.endsWith("target/classes") || s.contains("spring-data-commons");
+							}
+						}) // exclude test code
+						.withSlicing("sub-modules", // sub-modules are defined by any of the following pattern.
+								"org.springframework.data.jdbc.(**).*", //
+								"org.springframework.data.(**).*") //
+						.printTo("degraph-across-modules.graphml"), // writes a graphml to this location
+				JCheck.violationFree());
+	}
 }