topic [Activiti Explorer] NPE in LazyLoadingContainer in Alfresco Archive https://connect.hyland.com/t5/alfresco-archive/activiti-explorer-npe-in-lazyloadingcontainer/m-p/142496#M99775 <HTML><HEAD></HEAD><BODY><SPAN>Hi Activiti community,</SPAN><BR /><BR /><SPAN>We detected a NPE in Activiti Explorer, while trying to add a user in a group via the User Administration Panel.</SPAN><BR /><BR /><SPAN>Such try causes the following stacktrace :</SPAN><BR /><BR /><PRE class="language-none line-numbers"><CODE><BR />Caused by: java.lang.NullPointerException<BR />&nbsp;&nbsp;&nbsp;at org.activiti.explorer.data.LazyLoadingContainer.getContainerProperty(LazyLoadingContainer.java:87)<BR />&nbsp;&nbsp;&nbsp;at com.vaadin.ui.AbstractSelect.getContainerProperty(AbstractSelect.java:745)<BR />&nbsp;&nbsp;&nbsp;at com.vaadin.ui.Table.refreshRenderedCells(Table.java:1550)<BR />&nbsp;&nbsp;&nbsp;at com.vaadin.ui.Table.addContainerProperty(Table.java:3027)<BR />&nbsp;&nbsp;&nbsp;at org.activiti.explorer.ui.management.identity.GroupSelectionPopupWindow.initGroupTable(GroupSelectionPopupWindow.java:82)<BR />&nbsp;&nbsp;&nbsp;at org.activiti.explorer.ui.management.identity.GroupSelectionPopupWindow.&lt;init&gt;(GroupSelectionPopupWindow.java:64)<BR />&nbsp;&nbsp;&nbsp;at org.activiti.explorer.ui.management.identity.UserDetailPanel$6.buttonClick(UserDetailPanel.java:363)<BR />&nbsp;&nbsp;&nbsp;…<BR /><SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN></CODE></PRE><BR /><SPAN>You can reproduce the exception by deploying a fresh Activiti Explorer WAR and add some </SPAN><EM>assignement</EM><SPAN> and </SPAN><EM>security-role</EM><SPAN> groups.</SPAN><BR /><BR /><SPAN>After some investigation, the culprit is the </SPAN><STRONG>GroupSelectionQuery</STRONG><SPAN>. Indeed, the actual </SPAN><STRONG>loadItems()</STRONG><SPAN> implementation executes a paginated query and then filters result groups to retain only ones the user does not belong to. Thus it can cause a desynchronization of start and end indexes and throw NPE in the </SPAN><STRONG>LazyLoadingContainer.getContainerProperty()</STRONG><SPAN> method.</SPAN><BR /><BR /><SPAN>Here is how I temporarly fixed the problem :</SPAN><BR /><PRE class="language-none line-numbers"><CODE><BR />&nbsp;&nbsp;&nbsp; public List&lt;Item&gt; loadItems(int start, int count) {<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // Retrieve groups user belong to<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; Set&lt;String&gt; currentGroups = getCurrentGroups();<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // Retrieve all groups and remove ones that user is already member of<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; List&lt;Group&gt; groups = identityService.createGroupQuery().orderByGroupType().asc().orderByGroupId().asc().orderByGroupName().asc().list();<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; List&lt;Group&gt; groupsFiltered = new ArrayList&lt;Group&gt;();<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; for (Group group : groups) {<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; if (!currentGroups.contains(group.getId()))<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; groupsFiltered.add(group);<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; // Compute end index, extract sublist, create and populate result list<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; int end = start + count &lt;= groupsFiltered.size() ? start + count : groupsFiltered.size();<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; List&lt;Item&gt; groupItems = new ArrayList&lt;Item&gt;();<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; for (Group group : groupsFiltered.subList(start, end)) {<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; groupItems.add(new GroupSelectionItem(group));<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; }<BR />&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp;&nbsp; return groupItems;<BR />&nbsp;&nbsp;&nbsp; }<BR /><SPAN class="line-numbers-rows"><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN><SPAN>‍</SPAN></SPAN></CODE></PRE><BR /><SPAN>Please note this new implementation is no more lazy as it has to load all existing groups. I agree this could be more efficient but the </SPAN><STRONG>GroupQuery</STRONG><SPAN> builder currently does not allow search for groups that user does not belong to (we can only do the opposite, i.e. search for group the user belong to). I think add a new </SPAN><STRONG>groupNotMember()</STRONG><SPAN> method in the </SPAN><STRONG>GroupQuery</STRONG><SPAN> class could definitely fix the problem : the filtering would be done during the DB SELECT and return a consistent result set.</SPAN><BR /><BR /><SPAN>Nicolas</SPAN></BODY></HTML> Fri, 11 Jan 2013 19:47:57 GMT ncolomer 2013-01-11T19:47:57Z [Activiti Explorer] NPE in LazyLoadingContainer https://connect.hyland.com/t5/alfresco-archive/activiti-explorer-npe-in-lazyloadingcontainer/m-p/142496#M99775 Hi Activiti community,We detected a NPE in Activiti Explorer, while trying to add a user in a group via the User Administration Panel.Such try causes the following stacktrace :Caused by: java.lang.NullPointerException&nbsp;&nbsp;&nbsp;at org.activiti.explorer.data.LazyLoadingContainer.getContainerProperty(LazyLoad Fri, 11 Jan 2013 19:47:57 GMT https://connect.hyland.com/t5/alfresco-archive/activiti-explorer-npe-in-lazyloadingcontainer/m-p/142496#M99775 ncolomer 2013-01-11T19:47:57Z Re: [Activiti Explorer] NPE in LazyLoadingContainer https://connect.hyland.com/t5/alfresco-archive/activiti-explorer-npe-in-lazyloadingcontainer/m-p/142497#M99776 <HTML><HEAD></HEAD><BODY><SPAN>Is it possible to create a JIRA-issue for this, with your proposed solution attached? This way, we can both track it better, thanks!</SPAN></BODY></HTML> Tue, 15 Jan 2013 08:45:28 GMT https://connect.hyland.com/t5/alfresco-archive/activiti-explorer-npe-in-lazyloadingcontainer/m-p/142497#M99776 frederikherema1 2013-01-15T08:45:28Z