IDEA-55657 & other repository attach fixes

plugins/maven/facade-api/src/org/jetbrains/idea/maven/facade/MavenFacade.java

@@ -26,6 +26,8 @@ import java.util.Collection;
 import java.util.List;
 
 public interface MavenFacade extends Remote {
+  void ping() throws RemoteException;
+
   void set(MavenFacadeLogger logger, MavenFacadeDownloadListener downloadListener) throws RemoteException;
 
   MavenFacadeEmbedder createEmbedder(MavenFacadeSettings settings) throws RemoteException;

plugins/maven/facade-impl/src/org/jetbrains/idea/maven/facade/MavenFacadeImpl.java

@@ -36,6 +36,11 @@ import java.util.Collection;
 import java.util.List;
 
 public class MavenFacadeImpl extends RemoteObject implements MavenFacade {
+  @Override
+  public void ping() throws RemoteException {
+    // no op
+  }
+
   public void set(MavenFacadeLogger logger, MavenFacadeDownloadListener downloadListener) throws RemoteException {
     try {
       MavenFacadeGlobalsManager.set(logger, downloadListener);

plugins/maven/src/main/java/org/jetbrains/idea/maven/facade/MavenFacadeManager.java

@@ -114,11 +114,19 @@ public class MavenFacadeManager {
   }
 
   private synchronized MavenFacade getFacade() {
-    if (myFacade == null) {
+    try {
+      myFacade.ping();
+    }
+    catch (Exception ex) {
       try {
+        if (myFacade == null) {
+          UnicastRemoteObject.exportObject(myLogger, 0);
+          UnicastRemoteObject.exportObject(myDownloadListener, 0);
+        }
+        else {
+          // todo [anton] if myFacade != null reinit
+        }
         myFacade = mySupport.acquire(this, "");
-        UnicastRemoteObject.exportObject(myLogger, 0);
-        UnicastRemoteObject.exportObject(myDownloadListener, 0);
         myFacade.set(myLogger, myDownloadListener);
       }
       catch (Exception e) {

plugins/maven/src/main/java/org/jetbrains/idea/maven/project/MavenProjectsManager.java

@@ -74,7 +74,7 @@ public class MavenProjectsManager extends SimpleProjectComponent
 
   private MavenProjectsManagerState myState = new MavenProjectsManagerState();
 
-  private MavenEmbeddersManager myEmbeddersManager;
+  private final MavenEmbeddersManager myEmbeddersManager;
 
   private MavenProjectsTree myProjectsTree;
   private MavenProjectsManagerWatcher myWatcher;
@@ -103,6 +103,7 @@ public class MavenProjectsManager extends SimpleProjectComponent
 
   public MavenProjectsManager(Project project) {
     super(project);
+    myEmbeddersManager = new MavenEmbeddersManager(myProject);
   }
 
   public MavenProjectsManagerState getState() {
@@ -239,8 +240,6 @@ public class MavenProjectsManager extends SimpleProjectComponent
   }
 
   private void initWorkers() {
-    myEmbeddersManager = new MavenEmbeddersManager(myProject);
-
     myReadingProcessor = new MavenProjectsProcessor(myProject, ProjectBundle.message("maven.reading"), false, myEmbeddersManager);
     myResolvingProcessor = new MavenProjectsProcessor(myProject, ProjectBundle.message("maven.resolving"), true, myEmbeddersManager);
     myPluginsResolvingProcessor =

plugins/maven/src/main/java/org/jetbrains/idea/maven/utils/RepositoryAttachDialog.java

@@ -331,7 +331,7 @@ public class RepositoryAttachDialog extends DialogWrapper {
     }
     else {
       final Pair<MavenArtifactInfo, MavenRepositoryInfo> artifactAndRepo = myCoordinates.get(getCoordinateText());
-      final MavenRepositoryInfo repository = artifactAndRepo.second;
+      final MavenRepositoryInfo repository = artifactAndRepo == null? null : artifactAndRepo.second;
       return repository != null? Collections.singletonList(repository) : ContainerUtil.findAll(myRepositories.values(), Condition.NOT_NULL);
     }
   }