OO-553: improve "StringHelper.transformDisplayNameToFileSystemName" to remove...

OO-553: improve "StringHelper.transformDisplayNameToFileSystemName" to remove more special characters and all non-ascii characters in general

src/main/java/org/olat/core/util/StringHelper.java

@@ -324,10 +324,10 @@ public class StringHelper {
 	 * @return transformed string
 	 */
 	public static String transformDisplayNameToFileSystemName(String s){
-		s = s.replace('?', '_');
-		s = s.replace('/', '_');
-		s = s.replace(' ', '_');
-		return s;
+		//replace some separator with an underscore
+		s = s.replace('?', '_').replace('\\', '_').replace('/', '_').replace(' ', '_');
+		//remove all non-ascii characters
+		return FileUtils.normalizeFilename(s);
 	}
 	
 	public static boolean isLong(String string) {

src/test/java/org/olat/core/util/StringHelperTest.java

@@ -22,9 +22,8 @@ package org.olat.core.util;
 import static org.junit.Assert.assertFalse;
 import static org.junit.Assert.assertTrue;
 
+import org.junit.Assert;
 import org.junit.Test;
-import org.junit.runner.RunWith;
-import org.junit.runners.JUnit4;
 
 /**
  * Description:<br>
@@ -34,10 +33,8 @@ import org.junit.runners.JUnit4;
  * Initial Date:  13.07.2010 <br>
  * @author gnaegi
  */
-@RunWith(JUnit4.class)
 public class StringHelperTest {
 
-
 	@Test
 	public void testContainsNonWhitespace() {
 		// positive tests
@@ -53,4 +50,12 @@ public class StringHelperTest {
 		assertFalse(StringHelper.containsNonWhitespace("             "));
 		assertFalse(StringHelper.containsNonWhitespace("  \t  \r"));
 	}
+	
+	@Test
+	public void transformDisplayNameToFileSystemName() {
+		Assert.assertEquals("Webclass_Energie_2004_2005", StringHelper.transformDisplayNameToFileSystemName("Webclass Energie 2004/2005"));
+		Assert.assertEquals("Webclass_Energie_2004_2005", StringHelper.transformDisplayNameToFileSystemName("Webclass Energie 2004\\2005"));
+		Assert.assertEquals("Webclass_Energie_20042005", StringHelper.transformDisplayNameToFileSystemName("Webclass Energie 2004:2005"));
+		Assert.assertEquals("Webclaess", StringHelper.transformDisplayNameToFileSystemName("Webcl\u00E4ss"));
+	}
 }