2 files changed, 63 insertions, 18 deletions

diff --git a/packages/DocumentsUI/src/com/android/documentsui/model/DocumentInfo.java b/packages/DocumentsUI/src/com/android/documentsui/model/DocumentInfo.java
index 08a8c13..5091a61 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/model/DocumentInfo.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/model/DocumentInfo.java
@@ -23,6 +23,7 @@ import android.net.Uri;
 import android.os.Parcel;
 import android.os.Parcelable;
 import android.provider.DocumentsContract;
+import android.provider.DocumentsProvider;
 import android.provider.DocumentsContract.Document;
 
 import com.android.documentsui.RootCursorWrapper;
@@ -141,23 +142,42 @@ public class DocumentInfo implements Durable, Parcelable {
     }
 
     public static DocumentInfo fromCursor(Cursor cursor, String authority) {
-        final DocumentInfo doc = new DocumentInfo();
-        doc.authority = authority;
-        doc.documentId = getCursorString(cursor, Document.COLUMN_DOCUMENT_ID);
-        doc.mimeType = getCursorString(cursor, Document.COLUMN_MIME_TYPE);
-        doc.documentId = getCursorString(cursor, Document.COLUMN_DOCUMENT_ID);
-        doc.mimeType = getCursorString(cursor, Document.COLUMN_MIME_TYPE);
-        doc.displayName = getCursorString(cursor, Document.COLUMN_DISPLAY_NAME);
-        doc.lastModified = getCursorLong(cursor, Document.COLUMN_LAST_MODIFIED);
-        doc.flags = getCursorInt(cursor, Document.COLUMN_FLAGS);
-        doc.summary = getCursorString(cursor, Document.COLUMN_SUMMARY);
-        doc.size = getCursorLong(cursor, Document.COLUMN_SIZE);
-        doc.icon = getCursorInt(cursor, Document.COLUMN_ICON);
-        doc.deriveFields();
-        return doc;
-    }
-
-    public static DocumentInfo fromUri(ContentResolver resolver, Uri uri) throws FileNotFoundException {
+        final DocumentInfo info = new DocumentInfo();
+        info.updateFromCursor(cursor, authority);
+        return info;
+    }
+
+    public void updateFromCursor(Cursor cursor, String authority) {
+        this.authority = authority;
+        this.documentId = getCursorString(cursor, Document.COLUMN_DOCUMENT_ID);
+        this.mimeType = getCursorString(cursor, Document.COLUMN_MIME_TYPE);
+        this.documentId = getCursorString(cursor, Document.COLUMN_DOCUMENT_ID);
+        this.mimeType = getCursorString(cursor, Document.COLUMN_MIME_TYPE);
+        this.displayName = getCursorString(cursor, Document.COLUMN_DISPLAY_NAME);
+        this.lastModified = getCursorLong(cursor, Document.COLUMN_LAST_MODIFIED);
+        this.flags = getCursorInt(cursor, Document.COLUMN_FLAGS);
+        this.summary = getCursorString(cursor, Document.COLUMN_SUMMARY);
+        this.size = getCursorLong(cursor, Document.COLUMN_SIZE);
+        this.icon = getCursorInt(cursor, Document.COLUMN_ICON);
+        this.deriveFields();
+    }
+
+    public static DocumentInfo fromUri(ContentResolver resolver, Uri uri)
+            throws FileNotFoundException {
+        final DocumentInfo info = new DocumentInfo();
+        info.updateFromUri(resolver, uri);
+        return info;
+    }
+
+    /**
+     * Update a possibly stale restored document against a live
+     * {@link DocumentsProvider}.
+     */
+    public void updateSelf(ContentResolver resolver) throws FileNotFoundException {
+        updateFromUri(resolver, derivedUri);
+    }
+
+    public void updateFromUri(ContentResolver resolver, Uri uri) throws FileNotFoundException {
         final ContentProviderClient client = resolver.acquireUnstableContentProviderClient(
                 uri.getAuthority());
         Cursor cursor = null;
@@ -166,7 +186,7 @@ public class DocumentInfo implements Durable, Parcelable {
             if (!cursor.moveToFirst()) {
                 throw new FileNotFoundException("Missing details for " + uri);
             }
-            return fromCursor(cursor, uri.getAuthority());
+            updateFromCursor(cursor, uri.getAuthority());
         } catch (Throwable t) {
             throw asFileNotFoundException(t);
         } finally {
diff --git a/packages/DocumentsUI/src/com/android/documentsui/model/DocumentStack.java b/packages/DocumentsUI/src/com/android/documentsui/model/DocumentStack.java
index 2541440..0a378c0 100644
--- a/packages/DocumentsUI/src/com/android/documentsui/model/DocumentStack.java
+++ b/packages/DocumentsUI/src/com/android/documentsui/model/DocumentStack.java
@@ -16,10 +16,15 @@
 
 package com.android.documentsui.model;
 
+import android.content.ContentResolver;
+import android.provider.DocumentsProvider;
+
 import java.io.DataInputStream;
 import java.io.DataOutputStream;
+import java.io.FileNotFoundException;
 import java.io.IOException;
 import java.net.ProtocolException;
+import java.util.Collection;
 import java.util.LinkedList;
 
 /**
@@ -46,6 +51,26 @@ public class DocumentStack extends LinkedList<DocumentInfo> implements Durable {
         return size() == 0;
     }
 
+    public void updateRoot(Collection<RootInfo> matchingRoots) throws FileNotFoundException {
+        for (RootInfo root : matchingRoots) {
+            if (root.equals(this.root)) {
+                this.root = root;
+                return;
+            }
+        }
+        throw new FileNotFoundException("Failed to find matching root for " + root);
+    }
+
+    /**
+     * Update a possibly stale restored stack against a live
+     * {@link DocumentsProvider}.
+     */
+    public void updateDocuments(ContentResolver resolver) throws FileNotFoundException {
+        for (DocumentInfo info : this) {
+            info.updateSelf(resolver);
+        }
+    }
+
     @Override
     public void reset() {
         clear();