Can you please clarify what you do and when it crashes?

You click "New Attribute" in the entry editor, the "New Attribute" dialog pop up, you choose some "boolean" attribute, and click "Finish"? What happens then? Is the new (but empty) attribute visible in the entry editor? Does it switch to edit mode?

Do you get any additional error message?
Can you please check the logfile ~/.ApacheDirectoryStudio/.metadata/.log for any relevant message?
Is there a hs_err_<pid>.log in your home folder?

Is it visible in the entry editor and the boolean is a single-valued attribute. In the entry editor a message appears ">>> Error, the configured value editor can not handle this value!<<<"

Here is the logfile errors:

!ENTRY org.eclipse.ui 4 0 2016-12-28 08:36:07.400
!MESSAGE Unhandled event loop exception
!STACK 0
org.eclipse.core.runtime.AssertionFailedException: assertion failed:
at org.eclipse.core.runtime.Assert.isTrue(Assert.java:110)
at org.eclipse.core.runtime.Assert.isTrue(Assert.java:96)
at org.eclipse.jface.viewers.TextCellEditor.doSetValue(TextCellEditor.java:231)
at org.apache.directory.studio.valueeditors.AbstractInPlaceStringValueEditor.doSetValue(AbstractInPlaceStringValueEditor.java:230)
at org.eclipse.jface.viewers.CellEditor.setValue(CellEditor.java:861)
at org.eclipse.jface.viewers.EditingSupport.initializeCellEditorValue(EditingSupport.java:100)
at org.eclipse.jface.viewers.ColumnViewerEditor.activateCellEditor(ColumnViewerEditor.java:199)
at org.eclipse.jface.viewers.ColumnViewerEditor.handleEditorActivationEvent(ColumnViewerEditor.java:452)
at org.eclipse.jface.viewers.ColumnViewer.triggerEditorActivationEvent(ColumnViewer.java:676)
at org.eclipse.jface.viewers.ColumnViewer.editElement(ColumnViewer.java:422)
at org.eclipse.jface.viewers.TreeViewer.editElement(TreeViewer.java:1118)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.AbstractOpenEditorAction.activateEditor(AbstractOpenEditorAction.java:140)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.AbstractOpenEditorAction.run(AbstractOpenEditorAction.java:111)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.OpenBestEditorAction.run(OpenBestEditorAction.java:212)
at org.apache.directory.studio.ldapbrowser.common.actions.proxy.BrowserActionProxy.run(BrowserActionProxy.java:260)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.OpenDefaultEditorAction.run(OpenDefaultEditorAction.java:125)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.EntryEditorWidgetUniversalListener$1.widgetDefaultSelected(EntryEditorWidgetUniversalListener.java:94)
at org.eclipse.swt.widgets.TypedListener.handleEvent(TypedListener.java:119)
at org.eclipse.swt.widgets.EventTable.sendEvent(EventTable.java:84)
at org.eclipse.swt.widgets.Display.sendEvent(Display.java:4230)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1491)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1514)
at org.eclipse.swt.widgets.Widget.sendEvent(Widget.java:1499)
at org.eclipse.swt.widgets.Widget.notifyListeners(Widget.java:1299)
at org.eclipse.swt.widgets.Display.runDeferredEvents(Display.java:4072)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3698)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1127)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:337)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1018)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:694)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:337)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:606)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
at org.apache.directory.studio.Application.start(Application.java:51)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:669)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:608)
at org.eclipse.equinox.launcher.Main.run(Main.java:1515)

!ENTRY org.apache.directory.studio.common.core 4 4 2016-12-28 08:36:10.689
!MESSAGE Error while executing LDIF

• [LDAP: error code 21 - NDS error: no additional information available (-306)]
  !SUBENTRY 1 org.apache.directory.studio.common.core 4 4 2016-12-28 08:36:10.689
  !MESSAGE javax.naming.directory.InvalidAttributeValueException: [LDAP: error code 21 - NDS error: no additional information available (-306)]; remaining name 'cn=b93748,ou=EMPLOYEES,ou=NA,ou=INTERNAL,o=SAC'
  at com.sun.jndi.ldap.LdapCtx.mapErrorCode(LdapCtx.java:3148)
  at com.sun.jndi.ldap.LdapCtx.processReturnCode(LdapCtx.java:3081)
  at com.sun.jndi.ldap.LdapCtx.processReturnCode(LdapCtx.java:2888)
  at com.sun.jndi.ldap.LdapCtx.c_modifyAttributes(LdapCtx.java:1475)
  at com.sun.jndi.toolkit.ctx.ComponentDirContext.p_modifyAttributes(ComponentDirContext.java:277)
  at com.sun.jndi.toolkit.ctx.PartialCompositeDirContext.modifyAttributes(PartialCompositeDirContext.java:192)
  at org.apache.directory.studio.connection.core.io.jndi.JNDIConnectionWrapper$2.run(JNDIConnectionWrapper.java:455)
  at org.apache.directory.studio.connection.core.io.jndi.JNDIConnectionWrapper.runAndMonitor(JNDIConnectionWrapper.java:1304)
  at org.apache.directory.studio.connection.core.io.jndi.JNDIConnectionWrapper.checkConnectionAndRunAndMonitor(JNDIConnectionWrapper.java:1237)
  at org.apache.directory.studio.connection.core.io.jndi.JNDIConnectionWrapper.modifyEntry(JNDIConnectionWrapper.java:510)
  at org.apache.directory.studio.ldapbrowser.core.jobs.ImportLdifRunnable.importLdifRecord(ImportLdifRunnable.java:515)
  at org.apache.directory.studio.ldapbrowser.core.jobs.ImportLdifRunnable.importLdif(ImportLdifRunnable.java:272)
  at org.apache.directory.studio.ldapbrowser.core.jobs.ExecuteLdifRunnable.executeLdif(ExecuteLdifRunnable.java:157)
  at org.apache.directory.studio.ldapbrowser.core.jobs.ExecuteLdifRunnable.run(ExecuteLdifRunnable.java:123)
  at org.apache.directory.studio.ldapbrowser.core.jobs.UpdateEntryRunnable.run(UpdateEntryRunnable.java:59)
  at org.apache.directory.studio.connection.ui.RunnableContextRunner$1.run(RunnableContextRunner.java:116)
  at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:119)

!STACK 0
javax.naming.directory.InvalidAttributeValueException: [LDAP: error code 21 - NDS error: no additional information available (-306)]; remaining name 'cn=b93748,ou=EMPLOYEES,ou=NA,ou=INTERNAL,o=SAC'
at com.sun.jndi.ldap.LdapCtx.mapErrorCode(LdapCtx.java:3148)
at com.sun.jndi.ldap.LdapCtx.processReturnCode(LdapCtx.java:3081)
at com.sun.jndi.ldap.LdapCtx.processReturnCode(LdapCtx.java:2888)
at com.sun.jndi.ldap.LdapCtx.c_modifyAttributes(LdapCtx.java:1475)
at com.sun.jndi.toolkit.ctx.ComponentDirContext.p_modifyAttributes(ComponentDirContext.java:277)
at com.sun.jndi.toolkit.ctx.PartialCompositeDirContext.modifyAttributes(PartialCompositeDirContext.java:192)
at org.apache.directory.studio.connection.core.io.jndi.JNDIConnectionWrapper$2.run(JNDIConnectionWrapper.java:455)
at org.apache.directory.studio.connection.core.io.jndi.JNDIConnectionWrapper.runAndMonitor(JNDIConnectionWrapper.java:1304)
at org.apache.directory.studio.connection.core.io.jndi.JNDIConnectionWrapper.checkConnectionAndRunAndMonitor(JNDIConnectionWrapper.java:1237)
at org.apache.directory.studio.connection.core.io.jndi.JNDIConnectionWrapper.modifyEntry(JNDIConnectionWrapper.java:510)
at org.apache.directory.studio.ldapbrowser.core.jobs.ImportLdifRunnable.importLdifRecord(ImportLdifRunnable.java:515)
at org.apache.directory.studio.ldapbrowser.core.jobs.ImportLdifRunnable.importLdif(ImportLdifRunnable.java:272)
at org.apache.directory.studio.ldapbrowser.core.jobs.ExecuteLdifRunnable.executeLdif(ExecuteLdifRunnable.java:157)
at org.apache.directory.studio.ldapbrowser.core.jobs.ExecuteLdifRunnable.run(ExecuteLdifRunnable.java:123)
at org.apache.directory.studio.ldapbrowser.core.jobs.UpdateEntryRunnable.run(UpdateEntryRunnable.java:59)
at org.apache.directory.studio.connection.ui.RunnableContextRunner$1.run(RunnableContextRunner.java:116)
at org.eclipse.jface.operation.ModalContext$ModalContextThread.run(ModalContext.java:119)

!ENTRY org.eclipse.ui 4 4 2016-12-28 08:36:37.959
!MESSAGE Conflicting handlers for org.eclipse.ui.edit.text.contentAssist.proposals:

vs

!ENTRY org.eclipse.ui 4 0 2016-12-28 08:36:46.309
!MESSAGE Unhandled event loop exception
!STACK 0
org.eclipse.swt.SWTException: Failed to execute runnable (org.eclipse.core.runtime.AssertionFailedException: assertion failed: )
at org.eclipse.swt.SWT.error(SWT.java:4491)
at org.eclipse.swt.SWT.error(SWT.java:4406)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:138)
at org.eclipse.swt.widgets.Display.runAsyncMessages(Display.java:4024)
at org.eclipse.swt.widgets.Display.readAndDispatch(Display.java:3700)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine$4.run(PartRenderingEngine.java:1127)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:337)
at org.eclipse.e4.ui.internal.workbench.swt.PartRenderingEngine.run(PartRenderingEngine.java:1018)
at org.eclipse.e4.ui.internal.workbench.E4Workbench.createAndRunUI(E4Workbench.java:156)
at org.eclipse.ui.internal.Workbench$5.run(Workbench.java:694)
at org.eclipse.core.databinding.observable.Realm.runWithDefault(Realm.java:337)
at org.eclipse.ui.internal.Workbench.createAndRunWorkbench(Workbench.java:606)
at org.eclipse.ui.PlatformUI.createAndRunWorkbench(PlatformUI.java:150)
at org.apache.directory.studio.Application.start(Application.java:51)
at org.eclipse.equinox.internal.app.EclipseAppHandle.run(EclipseAppHandle.java:196)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.runApplication(EclipseAppLauncher.java:134)
at org.eclipse.core.runtime.internal.adaptor.EclipseAppLauncher.start(EclipseAppLauncher.java:104)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:380)
at org.eclipse.core.runtime.adaptor.EclipseStarter.run(EclipseStarter.java:235)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:498)
at org.eclipse.equinox.launcher.Main.invokeFramework(Main.java:669)
at org.eclipse.equinox.launcher.Main.basicRun(Main.java:608)
at org.eclipse.equinox.launcher.Main.run(Main.java:1515)
Caused by: org.eclipse.core.runtime.AssertionFailedException: assertion failed:
at org.eclipse.core.runtime.Assert.isTrue(Assert.java:110)
at org.eclipse.core.runtime.Assert.isTrue(Assert.java:96)
at org.eclipse.jface.viewers.TextCellEditor.doSetValue(TextCellEditor.java:231)
at org.apache.directory.studio.valueeditors.AbstractInPlaceStringValueEditor.doSetValue(AbstractInPlaceStringValueEditor.java:230)
at org.eclipse.jface.viewers.CellEditor.setValue(CellEditor.java:861)
at org.eclipse.jface.viewers.EditingSupport.initializeCellEditorValue(EditingSupport.java:100)
at org.eclipse.jface.viewers.ColumnViewerEditor.activateCellEditor(ColumnViewerEditor.java:199)
at org.eclipse.jface.viewers.ColumnViewerEditor.handleEditorActivationEvent(ColumnViewerEditor.java:452)
at org.eclipse.jface.viewers.ColumnViewer.triggerEditorActivationEvent(ColumnViewer.java:676)
at org.eclipse.jface.viewers.ColumnViewer.editElement(ColumnViewer.java:422)
at org.eclipse.jface.viewers.TreeViewer.editElement(TreeViewer.java:1118)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.AbstractOpenEditorAction.activateEditor(AbstractOpenEditorAction.java:140)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.AbstractOpenEditorAction.run(AbstractOpenEditorAction.java:111)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.OpenBestEditorAction.run(OpenBestEditorAction.java:212)
at org.apache.directory.studio.ldapbrowser.common.actions.proxy.BrowserActionProxy.run(BrowserActionProxy.java:260)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.OpenDefaultEditorAction.run(OpenDefaultEditorAction.java:125)
at org.apache.directory.studio.ldapbrowser.common.widgets.entryeditor.EntryEditorWidgetUniversalListener.entryUpdated(EntryEditorWidgetUniversalListener.java:264)
at org.apache.directory.studio.ldapbrowser.ui.editors.entry.EntryEditorUniversalListener.entryUpdated(EntryEditorUniversalListener.java:186)
at org.apache.directory.studio.ldapbrowser.core.events.EventRegistry$4$1.run(EventRegistry.java:237)
at org.eclipse.swt.widgets.RunnableLock.run(RunnableLock.java:35)
at org.eclipse.swt.widgets.Synchronizer.runAsyncMessages(Synchronizer.java:135)
... 23 more

hs_err log file attached

Ok, I have taken another approach to this problem. The thing is that the wizard dialog will never store anything in the value, it will be up to the associated editor to deal with the error message, if the value is incorrect (here, null for a boolean value). We can't set something different than null, because we don't know what would be the default value, and null is a valid value for many attributeTypes.

If I change the InPlaceBooleanValueEditor class, adding a doSetValue method that sets the value to "TRUE" by default, the browser does not crash anymore, but the text is seen as red (ie, an error). It does not freeze anymore when you double click on the value, but you can't save it immediately - ie, if you don't double-click on the value -, because the value is still seen as empty (actually the red "TRUE" is just an artefact in the TreeViwer, it's not yet a value associated to the Attribute...).

There is something missing that would not make the value seen as an error, but OTOH, it might be good enough : as soon as you double-click the value, it's validated.

So it's - again - an half backed solution, but a better one.

Stefan, any better idea ?

Side note : there is another problem (and I will open a new ticket for that). If you want to create an attribute with a null value, and this is legit, for instance for any attribute which syntax is IA5String for instance, you get a NPE :

Caused by: java.lang.RuntimeException: Empty value in attribute mail
	at org.apache.directory.studio.entryeditors.EntryEditorManager.saveSharedWorkingCopy(EntryEditorManager.java:991)
	at org.apache.directory.studio.entryeditors.EntryEditorInput.saveSharedWorkingCopy(EntryEditorInput.java:283)
...

The two issues are related, as we always set a null value in any added attribute, and we always expect the user to feed the value later on, marking it using the red color.

At this point, I'm wondering if adding a value editor call at the end of the attribute addition widget wouldn't be a better idea...

Seems to work on Mac now, probably fixed by Emmanuel in commits 1786559, 1786834, 1786868.