OO-861: upgrade requirement to JDK 1.7, add some 1.7 specific code and check...

OO-861: upgrade requirement to JDK 1.7, add some 1.7 specific code and check if all our build chain works

pom.xml

@@ -63,7 +63,7 @@
 		level if necessary. -->
 	<properties>
 		<project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
-		<targetJdk>1.6</targetJdk>
+		<targetJdk>1.7</targetJdk>
 		<org.springframework.version>3.2.4.RELEASE</org.springframework.version>
 		<org.hibernate.version>4.2.6.Final</org.hibernate.version>
 		<com.sun.jersey.version>1.17.1</com.sun.jersey.version>
@@ -1220,14 +1220,14 @@
 		<pluginManagement>
 			<plugins>
 
-				<!-- OLAT requires JDK 1.6 or later ! -->
+				<!-- OLAT requires JDK 1.7 or later ! -->
 				<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>
+						<source>1.7</source>
+						<target>1.7</target>
 						<encoding>UTF-8</encoding>
 					</configuration>
 				</plugin>
@@ -1318,7 +1318,7 @@
 										<version>2.2+</version>
 									</requireMavenVersion>
 									<requireJavaVersion>
-										<version>1.6+</version>
+										<version>1.7+</version>
 									</requireJavaVersion>
 								</rules>
 							</configuration>

src/main/java/org/olat/core/util/vfs/version/VersionsFileManager.java

@@ -22,6 +22,7 @@ package org.olat.core.util.vfs.version;
 import java.io.File;
 import java.io.IOException;
 import java.io.InputStream;
+import java.nio.file.Path;
 import java.util.ArrayList;
 import java.util.Calendar;
 import java.util.Date;
@@ -761,6 +762,11 @@ public class VersionsFileManager extends VersionsManager implements Initializabl
 			if (absolutPath.startsWith(getCanonicalRoot())) {
 				relPath = absolutPath.substring(getCanonicalRoot().length());
 			}
+			
+			Path path = impl.getBasefile().toPath();
+			Path relativePath = getCanonicalRootFile().toPath().relativize(path);
+			String relPath2 = "/" + relativePath.toString();
+			log.debug(relPath + " :: " + relPath2);
 		}
 		return relPath;
 	}
@@ -797,11 +803,15 @@ public class VersionsFileManager extends VersionsManager implements Initializabl
 		return null;
 	}
 
-	public String getCanonicalRoot() {
+	public File getCanonicalRootFile() {
 		if(rootFolder == null) {
 			rootFolder = new File(FolderConfig.getCanonicalRoot());
 		}
-		return rootFolder.getAbsolutePath();
+		return rootFolder;
+	}
+	
+	public String getCanonicalRoot() {
+		return getCanonicalRootFile().getAbsolutePath();
 	}
 	
 	public File getRootVersionsFile() {