eclipse plugin: if the paths object is not valid stop creating the project

utils/umc_dev/org.wesnoth/src/org/wesnoth/Messages.java

@@ -164,6 +164,7 @@ public class Messages extends NLS
     public static String        ProjectUtils_0;
     public static String        ProjectUtils_4;
     public static String        ProjectUtils_6;
+    public static String ProjectUtils_7;
     public static String        ResourceUtils_5;
     public static String        ScenarioNewWizard_0;
     public static String        ScenarioNewWizard_2;

utils/umc_dev/org.wesnoth/src/org/wesnoth/installs/WesnothInstallsUtils.java

@@ -189,9 +189,8 @@ public class WesnothInstallsUtils
             }
 
             if( GUIUtils
-                .showMessageBox( String.format(
-                    Messages.WesnothInstallsUtils_1, resource
-                        .getProject( ).getName( ) ),
+                .showMessageBox( String.format( Messages.WesnothInstallsUtils_1,
+                    resource.getProject( ).getName( ) ),
                     SWT.ICON_QUESTION | SWT.YES | SWT.NO ) == SWT.NO ) {
                 return false; // no hope :(
             }

utils/umc_dev/org.wesnoth/src/org/wesnoth/messages.properties

@@ -147,6 +147,7 @@ PreprocessorUtils_12=The file is null or does not exist
 ProjectUtils_0=Cleaning files...
 ProjectUtils_4=Creating project '%s' ...
 ProjectUtils_6=Configuring project...
+ProjectUtils_7=Please select a valid install, or create one if none exists.
 ResourceUtils_5=Error creating the resource
 ScenarioNewWizard_0=Create a new scenario
 ScenarioNewWizard_2=Creating 

utils/umc_dev/org.wesnoth/src/org/wesnoth/preferences/Preferences.java

@@ -315,6 +315,11 @@ public class Preferences extends AbstractPreferenceInitializer
             installName_ = installName;
         }
 
+        public boolean isValid( )
+        {
+            return installName_ != null && ! installName_.isEmpty( );
+        }
+
         /**
          * Returns the install name associated with this instance
          * 

utils/umc_dev/org.wesnoth/src/org/wesnoth/projects/ProjectUtils.java

@@ -31,6 +31,7 @@ import org.wesnoth.preferences.Preferences;
 import org.wesnoth.preferences.Preferences.Paths;
 import org.wesnoth.templates.ReplaceableParameter;
 import org.wesnoth.templates.TemplateProvider;
+import org.wesnoth.utils.GUIUtils;
 import org.wesnoth.utils.ResourceUtils;
 import org.wesnoth.utils.StringUtils;
 import org.wesnoth.views.WesnothProjectsExplorer;
@@ -106,6 +107,11 @@ public class ProjectUtils
     {
         ProjectCache cache = getCacheForProject( project );
         Paths paths = Preferences.getPaths( cache.getInstallName( ) );
+
+        if( ! paths.isValid( ) ) {
+            return false;
+        }
+
         IFolder coreLibrary = project
             .getFolder( WesnothProjectsExplorer.CORE_LIBRARY_NAME );
 
@@ -115,17 +121,15 @@ public class ProjectUtils
                 if( coreLibrary.exists( ) ) {
                     // the new Core Library will point to the same location.
                     // Skip it then.
-                    if( coreLibrary.getLocation( ).equals(
-                        paths.getCoreDirPath( ) ) ) {
+                    if( coreLibrary.getLocation( ).equals( paths.getCoreDirPath( ) ) ) {
                         return true;
                     }
 
                     coreLibrary.delete( true, new NullProgressMonitor( ) );
                 }
 
-                coreLibrary
-                    .createLink( paths.getCoreDirPath( ), updateFlags,
-                        new NullProgressMonitor( ) );
+                coreLibrary.createLink( paths.getCoreDirPath( ), updateFlags,
+                    new NullProgressMonitor( ) );
 
                 coreLibrary.setDerived( true, new NullProgressMonitor( ) );
             } catch( CoreException e ) {
@@ -135,10 +139,10 @@ public class ProjectUtils
         }
         else {
             Logger.getInstance( ).log(
-                "Couldn't create link on:" + paths.getCoreDir( )
-                    + "; project: " + project.getName( ),
-                "Cannot create the Wesnoth Core Library folder for project "
-                    + project.getName( ) + "!" );
+                "Couldn't create link on:" + paths.getCoreDir( ) //$NON-NLS-1$
+                    + "; project: " + project.getName( ), //$NON-NLS-1$
+                "Cannot create the Wesnoth Core Library folder for project " //$NON-NLS-1$
+                    + project.getName( ) + "!" ); //$NON-NLS-1$
             return false;
         }
 
@@ -237,6 +241,11 @@ public class ProjectUtils
             return - 1;
         }
 
+        if( installName.isEmpty( ) ) {
+            GUIUtils.showErrorMessageBox( Messages.ProjectUtils_7 );
+            return - 1;
+        }
+
         try {
             String projectPath = null;
 
@@ -251,7 +260,7 @@ public class ProjectUtils
                 // project is in workspace
                 projectPath = ResourcesPlugin.getWorkspace( ).getRoot( )
                     .getLocation( ).toOSString( )
-                    + "/" + handle.getProject( ).getName( );
+                    + "/" + handle.getProject( ).getName( ); //$NON-NLS-1$
             }
 
             monitor.subTask( Messages.ProjectUtils_0 );