diff -r cdd693dc844c masterfs/apichanges.xml
--- a/masterfs/apichanges.xml	Thu Mar 13 10:31:56 2008 +0100
+++ b/masterfs/apichanges.xml	Thu Mar 13 17:45:37 2008 +0100
@@ -46,6 +46,22 @@ made subject to such option by the copyr
         <apidef name="masterfs">MasterFileSystem API</apidef>
     </apidefs>
     <changes>
+        <change id="added-canWrite-friend-contract-for-versioning-systems">
+            <api name="masterfs"/>
+            <summary><code>ProvidedExtensions.canWrite</code> was added.</summary>
+            <version major="2" minor="14"/>
+            <date day="20" month="3" year="2008"/>
+            <author login="msandor"/>
+            <compatibility addition="yes" binary="compatible" source="compatible" semantic="compatible" deprecation="no" deletion="no" modification="no"/>
+            <description>
+                <p>
+                    <code>ProvidedExtensions.canWrite</code> which is called when
+                    <code>MasterFileSystem</code> queries the <code>FileObject</code> for writability.
+                </p>                
+            </description>
+            <issue number="130044"/>
+        </change>                        
+        
         <change id="fileobject-instances-are-not-issued-after-external-changes">
             <api name="masterfs"/>
             <summary>Fileobject instances are not issued after external changes</summary>
diff -r cdd693dc844c masterfs/manifest.mf
--- a/masterfs/manifest.mf	Thu Mar 13 10:31:56 2008 +0100
+++ b/masterfs/manifest.mf	Thu Mar 13 17:45:37 2008 +0100
@@ -1,7 +1,7 @@ Manifest-Version: 1.0
 Manifest-Version: 1.0
 OpenIDE-Module: org.netbeans.modules.masterfs/2
 OpenIDE-Module-Localizing-Bundle: org/netbeans/modules/masterfs/resources/Bundle.properties
-OpenIDE-Module-Specification-Version: 1.13
+OpenIDE-Module-Specification-Version: 1.14
 AutoUpdate-Show-In-Client: false
 AutoUpdate-Essential-Module: true
 
diff -r cdd693dc844c masterfs/src/org/netbeans/modules/masterfs/ProvidedExtensionsProxy.java
--- a/masterfs/src/org/netbeans/modules/masterfs/ProvidedExtensionsProxy.java	Thu Mar 13 10:31:56 2008 +0100
+++ b/masterfs/src/org/netbeans/modules/masterfs/ProvidedExtensionsProxy.java	Thu Mar 13 17:45:37 2008 +0100
@@ -190,6 +190,23 @@ public class ProvidedExtensionsProxy ext
         }
     }       
 
+    public boolean canWrite(final File f) {
+        final Boolean ret[] = new Boolean [] { null };
+        for (Iterator it = annotationProviders.iterator(); it.hasNext();) {
+            AnnotationProvider provider = (AnnotationProvider) it.next();
+            final InterceptionListener iListener = (provider != null) ?  provider.getInterceptionListener() : null;
+            if (iListener instanceof ProvidedExtensions) {
+                runCheckCode(new Runnable() {
+                    public void run() {
+                        ret[0] = ((ProvidedExtensions)iListener).canWrite(f);
+                    }
+                });                                                                                
+            }
+        }
+        return ret[0] != null ? ret[0] : super.canWrite(f);
+    }
+        
+    
     public void beforeChange(final FileObject f) {    
         for (Iterator it = annotationProviders.iterator(); it.hasNext();) {
             AnnotationProvider provider = (AnnotationProvider) it.next();
diff -r cdd693dc844c masterfs/src/org/netbeans/modules/masterfs/filebasedfs/fileobjects/BaseFileObj.java
--- a/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/fileobjects/BaseFileObj.java	Thu Mar 13 10:31:56 2008 +0100
+++ b/masterfs/src/org/netbeans/modules/masterfs/filebasedfs/fileobjects/BaseFileObj.java	Thu Mar 13 17:45:37 2008 +0100
@@ -140,7 +140,8 @@ public abstract class BaseFileObj extend
 
     public boolean canWrite() {
         final File file = getFileName().getFile();        
-        return file.canWrite();
+        ProvidedExtensions extension = getProvidedExtensions();
+        return extension.canWrite(file);
     }
 
     public final boolean isData() {
@@ -374,7 +375,8 @@ public abstract class BaseFileObj extend
 
     public boolean isReadOnly() {
         final File f = getFileName().getFile();
-        return !f.canWrite() && FileChangedManager.getInstance().exists(f);
+        ProvidedExtensions extension = getProvidedExtensions();
+        return !extension.canWrite(f) && FileChangedManager.getInstance().exists(f);
     }
 
     public final FileObject getParent() {
diff -r cdd693dc844c masterfs/src/org/netbeans/modules/masterfs/providers/ProvidedExtensions.java
--- a/masterfs/src/org/netbeans/modules/masterfs/providers/ProvidedExtensions.java	Thu Mar 13 10:31:56 2008 +0100
+++ b/masterfs/src/org/netbeans/modules/masterfs/providers/ProvidedExtensions.java	Thu Mar 13 17:45:37 2008 +0100
@@ -138,6 +138,17 @@ public class ProvidedExtensions implemen
     public void deleteFailure(FileObject fo) {}
     public void beforeDelete(FileObject fo) {}
 
+    /**
+     * Called by <code>MasterFileSystem</code> when <code>FileObject</code> is queried for writability with the
+     * canWrite() method.
+     * 
+     * @param f a file to query
+     * @return true if the file can be written to, deleted or moved, false otherwise
+     * @since 2.14
+     */
+    public boolean canWrite(File f) {         
+        return f.canWrite(); 
+    }
 
     /*
      * Called by <code>MasterFileSystem</code> when <code>FileObject</code>
diff -r cdd693dc844c masterfs/test/unit/src/org/netbeans/modules/masterfs/providers/ProvidedExtensionsTest.java
--- a/masterfs/test/unit/src/org/netbeans/modules/masterfs/providers/ProvidedExtensionsTest.java	Thu Mar 13 10:31:56 2008 +0100
+++ b/masterfs/test/unit/src/org/netbeans/modules/masterfs/providers/ProvidedExtensionsTest.java	Thu Mar 13 17:45:37 2008 +0100
@@ -135,6 +135,16 @@ public class ProvidedExtensionsTest exte
             os.close();
         }
         
+    }
+
+    public void testImplsCanWrite() throws IOException {
+        FileObject fo = FileUtil.toFileObject(getWorkDir());
+        assertNotNull(fo);
+        assertNotNull(iListener);
+        FileObject toChange = fo.createData("cw");
+        assertNotNull(toChange);
+        boolean cw = toChange.canWrite();
+        assertEquals(1, iListener.implsCanWriteCalls);            
     }
     
     public void testImplsMove() throws IOException {
@@ -440,6 +450,7 @@ public class ProvidedExtensionsTest exte
         private int implsCreateSuccessCalls;        
         private int implsFileLockCalls;
         private int implsFileUnlockCalls;
+        private int implsCanWriteCalls;
         
         private static  boolean implsMoveRetVal = true;
         private static boolean implsRenameRetVal = true;
@@ -455,6 +466,12 @@ public class ProvidedExtensionsTest exte
             implsBeforeChangeCalls = 0;
             implsCreateSuccessCalls = 0;
             implsFileLockCalls = 0;
+            implsCanWriteCalls = 0;
+        }
+
+        public boolean canWrite(File f) {
+            implsCanWriteCalls++;
+            return super.canWrite(f);
         }
 
         public void fileLocked(FileObject fo) {