Unable to load project due to missing dependency

[mathbagu]

When I change the dependencies of my project (removing for instance CGMES importer), the loading of a project fails and an error message is displayed to the user.

2018-12-18 08:47:44,089 ERROR [JavaFX Application Thread] c.p.g.u.GseUtil [GseUtil.java:139] com.powsybl.afs.AfsException: Importer not found for format CGMES
com.powsybl.afs.AfsException: Importer not found for format CGMES
	at com.powsybl.afs.ext.base.ImportedCase.lambda$getImporter$1(ImportedCase.java:67)
	at java.util.Optional.orElseThrow(Optional.java:290)
	at com.powsybl.afs.ext.base.ImportedCase.getImporter(ImportedCase.java:67)
	at com.powsybl.gse.afs.ext.base.BaseExtNodeGraphicProvider.getGraphic(BaseExtNodeGraphicProvider.java:58)
	at com.powsybl.gse.util.NodeGraphics.getGraphic(NodeGraphics.java:35)
	at com.powsybl.gse.app.ProjectPane.createFileTreeItem(ProjectPane.java:535)
	at com.powsybl.gse.app.ProjectPane.createNodeTreeItem(ProjectPane.java:481)
	at java.util.stream.ReferencePipeline$3$1.accept(ReferencePipeline.java:193)
	at java.util.ArrayList$ArrayListSpliterator.forEachRemaining(ArrayList.java:1382)
	at java.util.stream.AbstractPipeline.copyInto(AbstractPipeline.java:481)
	at java.util.stream.AbstractPipeline.wrapAndCopyInto(AbstractPipeline.java:471)
	at java.util.stream.ReduceOps$ReduceOp.evaluateSequential(ReduceOps.java:708)
	at java.util.stream.AbstractPipeline.evaluate(AbstractPipeline.java:234)
	at java.util.stream.ReferencePipeline.collect(ReferencePipeline.java:499)
	at com.powsybl.gse.app.ProjectPane.lambda$null$7(ProjectPane.java:507)
	at com.powsybl.gse.util.GseUtil.lambda$execute$4(GseUtil.java:130)
	at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
	at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
	at java.lang.Thread.run(Thread.java:748)

I think we have two options here:

• close the project, because it is unusable
• catch the exception, load the rest of the project and set as unknown this node (like in node chooser)