OO-529: implement sorting for groups in the member view

src/main/java/org/olat/group/ui/main/AbstractMemberListController.java

@@ -19,6 +19,7 @@
  */
 package org.olat.group.ui.main;
 
+import java.text.Collator;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.HashMap;
@@ -125,6 +126,7 @@ public abstract class AbstractMemberListController extends BasicController imple
 	private final BusinessGroupModule groupModule;
 	private final ACService acService;
 	
+	private final GroupMemberViewComparator memberViewComparator;
 	private static final CourseMembershipComparator MEMBERSHIP_COMPARATOR = new CourseMembershipComparator();
 	
 	public AbstractMemberListController(UserRequest ureq, WindowControl wControl, RepositoryEntry repoEntry, String page) {
@@ -148,6 +150,8 @@ public abstract class AbstractMemberListController extends BasicController imple
 		businessGroupService = CoreSpringFactory.getImpl(BusinessGroupService.class);
 		groupModule = CoreSpringFactory.getImpl(BusinessGroupModule.class);
 		acService = CoreSpringFactory.getImpl(ACService.class);
+		
+		memberViewComparator = new GroupMemberViewComparator(Collator.getInstance(getLocale()));
 
 		isAdministrativeUser = securityModule.isUserAllowedAdminProps(ureq.getUserSession().getRoles());
 		mainVC = createVelocityContainer(page);
@@ -202,14 +206,23 @@ public abstract class AbstractMemberListController extends BasicController imple
 				Object b = table.getTableDataModel().getValueAt(rowb,dataColumn);
 				if(a instanceof CourseMembership && b instanceof CourseMembership) {
 					return MEMBERSHIP_COMPARATOR.compare((CourseMembership)a, (CourseMembership)b);
-				} else {
-					return super.compareTo(rowa, rowb);
 				}
+				return super.compareTo(rowa, rowb);
 			}
 		});
 		if(repoEntry != null) {
 			CustomCellRenderer groupRenderer = new GroupCellRenderer();
-			memberListCtr.addColumnDescriptor(new CustomRenderColumnDescriptor(Cols.groups.i18n(), Cols.groups.ordinal(), null, getLocale(),  ColumnDescriptor.ALIGNMENT_LEFT, groupRenderer));
+			memberListCtr.addColumnDescriptor(new CustomRenderColumnDescriptor(Cols.groups.i18n(), Cols.groups.ordinal(), null, getLocale(),  ColumnDescriptor.ALIGNMENT_LEFT, groupRenderer) {
+				@Override
+				public int compareTo(final int rowa, final int rowb) {
+					Object a = table.getTableDataModel().getValueAt(rowa,dataColumn);
+					Object b = table.getTableDataModel().getValueAt(rowb,dataColumn);
+					if(a instanceof MemberView && b instanceof MemberView) {
+						return memberViewComparator.compare((MemberView)a, (MemberView)b);
+					}
+					return super.compareTo(rowa, rowb);
+				}
+			});
 		}
 		
 		memberListCtr.addColumnDescriptor(new GraduateColumnDescriptor("table.header.graduate", TABLE_ACTION_GRADUATE, getTranslator()));

src/main/java/org/olat/group/ui/main/GroupMemberViewComparator.java

+/**
+ * <a href="http://www.openolat.org">
+ * OpenOLAT - Online Learning and Training</a><br>
+ * <p>
+ * Licensed under the Apache License, Version 2.0 (the "License"); <br>
+ * you may not use this file except in compliance with the License.<br>
+ * You may obtain a copy of the License at the
+ * <a href="http://www.apache.org/licenses/LICENSE-2.0">Apache homepage</a>
+ * <p>
+ * Unless required by applicable law or agreed to in writing,<br>
+ * software distributed under the License is distributed on an "AS IS" BASIS, <br>
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. <br>
+ * See the License for the specific language governing permissions and <br>
+ * limitations under the License.
+ * <p>
+ * Initial code contributed and copyrighted by<br>
+ * frentix GmbH, http://www.frentix.com
+ * <p>
+ */
+package org.olat.group.ui.main;
+
+import java.text.Collator;
+import java.util.Comparator;
+import java.util.List;
+
+import org.olat.group.BusinessGroupShort;
+
+/**
+ * Compare the groups of member views based on the group name.<br/>
+ * 
+ * Initial date: 04.02.2013<br>
+ * @author srosse, stephane.rosse@frentix.com, http://www.frentix.com
+ *
+ */
+public class GroupMemberViewComparator implements Comparator<MemberView> {
+	
+	private Collator collator;
+	
+	public GroupMemberViewComparator(Collator collator) {
+		this.collator = collator;
+	}
+
+	@Override
+	public int compare(MemberView m1, MemberView m2) {
+		List<BusinessGroupShort> g1 = m1.getGroups();
+		List<BusinessGroupShort> g2 = m2.getGroups();
+		
+		if(g1 == null || g1.isEmpty()) {
+			if(g2 == null || g2.isEmpty()) return 0;
+			return -1;
+		}
+		if(g2 == null || g2.isEmpty()) return 1;
+		
+		int maxLevel = Math.max(g1.size(), g2.size());
+		
+		int compare = 0;
+		for(int i=0; i<maxLevel && compare==0; i++) {
+			BusinessGroupShort gs1 = i < g1.size() ? g1.get(i) : null;
+			BusinessGroupShort gs2 = i < g2.size() ? g2.get(i) : null;
+			compare = compareLevel(gs1, gs2);
+		}
+		return compare;
+	}
+	
+	private int compareLevel(BusinessGroupShort g1, BusinessGroupShort g2) {
+		if(g1 == null) {
+			if(g2 == null) return 0;
+			return -1;
+		}
+		if(g2 == null) return 1;
+		
+		String n1 = g1.getName();
+		String n2 = g2.getName();
+		if(n1 == null) {
+			if(n2 == null) return 0;
+			return -1;
+		}
+		if(n2 == null) return 1;
+		return collator == null ? n1.compareTo(n2) : collator.compare(n1, n2);	
+	}
+}