We don't currently have any committers actively working on tomahawk. The original JIRA for that was https://issues.apache.org/jira/browse/TOMAHAWK-952 and it looks like I only started to do the groundwork add that support.
As this was 10 years ago, I don't really remember any details about it. My clients have long ago switched over to primefaces. I have only one legacy app in maintenance mode that uses tomahawk, so I doubt I will ever revisit working on this. Your best bet is to file a bug and propose a fix in the form of a unified diff. While someone (maybe me) will apply that fix, I don't know if we have any plans to do an official tomahawk release any time soon. >From my email, it looks like part of the problem was determining how to maintain backwards compatibility short of subclassing the model. I guess you could try a delegating approach. Sorry, but I doubt I will be of any more help than that. On Tue, Jul 25, 2017 at 8:01 AM, s-awinte <s-awi...@haw-landshut.de> wrote: > Hi, > > I'm currently trying to use a <t:commandSortHeader> Tomahawk tag inside > <t:column defaultSorted="true" sortable="true"> with auto sorting, similar > to the example here: > https://wiki.apache.org/myfaces/Working_with_auto_sortable_tables > > Problem is, the tag's "propertyName" references to a string property of an > attribute of a given entity object (which itself does not extend > BaseSortableModel) and the entity's attribute is optional (nullable), which > will lead to a NestedNullException: > > ERROR [org.apache.myfaces.component.html.ext.SortableModel]... > org.apache.commons.beanutils.NestedNullException: Null property value for > 'attribute.shortName' on bean class 'class > com.my.app.model.food.exotic.fruit' > ... > javax.faces.FacesException: java.lang.IllegalArgumentException: Comparison > method violates its general contract! > at > javax.faces.component.UIComponentBase$AttributesMap.get(UIComponentBase.java:2352) > ... > Caused by: java.lang.IllegalArgumentException: Comparison method violates > its general contract! > at java.util.TimSort.mergeLo(TimSort.java:777) [rt.jar:1.8.0_60] > at java.util.TimSort.mergeAt(TimSort.java:514) [rt.jar:1.8.0_60] > at java.util.TimSort.mergeCollapse(TimSort.java:439) [rt.jar:1.8.0_60] > at java.util.TimSort.sort(TimSort.java:245) [rt.jar:1.8.0_60] > at java.util.Arrays.sort(Arrays.java:1512) [rt.jar:1.8.0_60] > at java.util.ArrayList.sort(ArrayList.java:1454) [rt.jar:1.8.0_60] > at java.util.Collections.sort(Collections.java:175) [rt.jar:1.8.0_60] > at > org.apache.myfaces.component.html.ext.BaseSortableModel.sort(BaseSortableModel.java:201) > [tomahawk20-1.1.14.jar:1.1.14] > at > org.apache.myfaces.component.html.ext.BaseSortableModel.setComparator(BaseSortableModel.java:62) > [tomahawk20-1.1.14.jar:1.1.14] > at > org.apache.myfaces.component.html.ext.SortableModel.setSortCriteria(SortableModel.java:143) > [tomahawk20-1.1.14.jar:1.1.14] > at > org.apache.myfaces.component.html.ext.AbstractHtmlDataTable.createDataModel(AbstractHtmlDataTable.java:1643) > [tomahawk20-1.1.14.jar:1.1.14] > at > org.apache.myfaces.component.html.ext.HtmlDataTableHack.getDataModel(HtmlDataTableHack.java:932) > [tomahawk20-1.1.14.jar:1.1.14] > at > org.apache.myfaces.component.html.ext.AbstractHtmlDataTable.getDataModel(AbstractHtmlDataTable.java:1597) > [tomahawk20-1.1.14.jar:1.1.14] > at > org.apache.myfaces.component.html.ext.HtmlDataTableHack.getRowCount(HtmlDataTableHack.java:103) > [tomahawk20-1.1.14.jar:1.1.14] > at sun.reflect.GeneratedMethodAccessor32969.invoke(Unknown Source) > [:1.8.0_60] > at > sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43) > [rt.jar:1.8.0_60] > at java.lang.reflect.Method.invoke(Method.java:497) [rt.jar:1.8.0_60] > ... > > > As I understand it, the row Objects of a sortable <t:dataTable> column are > being automatically wrapped in SortableModel, which brings its own > "RowDataComparator" via BaseSortableModel.sort(), which seems to be > > a) not null-safe (for the wrapped model) > b) not supporting nulls first/last > c) in this case violating the Comparator contract > > Regardless of the contract violation problem (probably due to a > NestedNullException inside RowDataComparator or because > BaseSortableModel.sort() never returning -1), I'd like in general to be able > to use a custom Comparator here, which can handle nested nulls and > implements a customized comparison, but <t:commandSortHeader> does not seem > to support this. > > Most references I find, completely ignore the commandSortHeader auto-sorting > and do the implement a custom backing Bean.sort(), an approach I'd like to > avoid, if possible. > > There would seem to exist a solution for the problem in this somewhat dated > example here, but it's unclear to me, if it ever managed to make it into > tomahawk's code base: > http://grokbase.com/t/myfaces/dev/073ev810b8/sortablemodel-and-t-datatable-changes-improvements > > In Trinidad, it would seem, that there was a similar (now resolved) issue: > https://issues.apache.org/jira/browse/TRINIDAD-1965 > > I could not figure out how this applies to Tomahawk, though, or if the > example above has been implemented by now, and I could not find any working > code example that would support this assumption. > > Also, I do not see how SortableModel.setSortCriteria() -> > BaseSortableModel.setComparator() could be utilized in this scenario without > letting the entity model extend BaseSortableModel or SortableModel, which > seems not feasable, due to my model already extending several other classes. > Is using a custom Comparator not supported in Tomahawk still, or, if so, > where can I find code examples or documentation describing how to use this > feature? > > If not, are you planning on fixing this issue anytime soon and should I file > a bug about the NestedNullException / contract violation problem, too? > > > Best regards, > Sawin
