Don't load all resources when syncing, only as needed.

app/src/main/java/at/bitfire/davdroid/resource/LocalAddressBook.java

@@ -18,6 +18,7 @@ import android.os.Build;
 import android.os.Bundle;
 import android.os.Parcel;
 import android.os.RemoteException;
+import android.provider.CalendarContract;
 import android.provider.ContactsContract;
 import android.provider.ContactsContract.Groups;
 import android.provider.ContactsContract.RawContacts;
@@ -30,6 +31,7 @@ import java.util.List;
 import java.util.logging.Level;
 
 import at.bitfire.davdroid.App;
+import at.bitfire.ical4android.CalendarStorageException;
 import at.bitfire.vcard4android.AndroidAddressBook;
 import at.bitfire.vcard4android.AndroidContact;
 import at.bitfire.vcard4android.AndroidGroup;
@@ -149,6 +151,15 @@ public class LocalAddressBook extends AndroidAddressBook implements LocalCollect
         return nameless.toArray(new LocalResource[nameless.size()]);
     }
 
+    @Override
+    public LocalResource getByUid(String uid) throws ContactsStorageException {
+        LocalContact[] ret = (LocalContact[]) queryContacts(AndroidContact.COLUMN_FILENAME + " =? ", new String[]{uid});
+        if (ret != null && ret.length > 0) {
+            return ret[0];
+        }
+        return null;
+    }
+
     public void deleteAll() throws ContactsStorageException {
         try {
             provider.delete(syncAdapterURI(RawContacts.CONTENT_URI), null, null);

app/src/main/java/at/bitfire/davdroid/resource/LocalCalendar.java

@@ -125,6 +125,15 @@ public class LocalCalendar extends AndroidCalendar implements LocalCollection {
         return (LocalEvent[])queryEvents(Events._SYNC_ID + " IS NULL AND " + Events.ORIGINAL_ID + " IS NULL", null);
     }
 
+    @Override
+    public LocalEvent getByUid(String uid) throws CalendarStorageException {
+        LocalEvent[] ret = (LocalEvent[]) queryEvents(Events._SYNC_ID + " =? ", new String[]{uid});
+        if (ret != null && ret.length > 0) {
+            return ret[0];
+        }
+        return null;
+    }
+
     @Override
     public LocalResource[] getDirty() throws CalendarStorageException, FileNotFoundException {
         List<LocalResource> dirty = new LinkedList<>();

app/src/main/java/at/bitfire/davdroid/resource/LocalCollection.java

@@ -21,6 +21,7 @@ public interface LocalCollection {
     LocalResource[] getDirty() throws CalendarStorageException, ContactsStorageException, FileNotFoundException;
 
     LocalResource[] getAll() throws CalendarStorageException, ContactsStorageException;
+    LocalResource getByUid(String uid) throws CalendarStorageException, ContactsStorageException;
 
     String getCTag() throws CalendarStorageException, ContactsStorageException;
     void setCTag(String cTag) throws CalendarStorageException, ContactsStorageException;

app/src/main/java/at/bitfire/davdroid/resource/LocalTaskList.java

@@ -17,6 +17,7 @@ import android.database.Cursor;
 import android.net.Uri;
 import android.os.Build;
 import android.os.RemoteException;
+import android.provider.CalendarContract;
 import android.support.annotation.NonNull;
 
 import org.dmfs.provider.tasks.TaskContract.TaskLists;
@@ -93,6 +94,15 @@ public class LocalTaskList extends AndroidTaskList implements LocalCollection {
         return (LocalTask[])queryTasks(Tasks._SYNC_ID + " IS NULL", null);
     }
 
+    @Override
+    public LocalTask getByUid(String uid) throws CalendarStorageException {
+        LocalTask[] ret = (LocalTask[]) queryTasks(Tasks._SYNC_ID + " =? ", new String[]{uid});
+        if (ret != null && ret.length > 0) {
+            return ret[0];
+        }
+        return null;
+    }
+
     @Override
     public LocalResource[] getDirty() throws CalendarStorageException, FileNotFoundException {
         LocalTask[] tasks = (LocalTask[])queryTasks(Tasks._DIRTY + "!=0 AND " + Tasks._DELETED + "== 0", null);

app/src/main/java/at/bitfire/davdroid/syncadapter/CalendarSyncManager.java

@@ -96,25 +96,18 @@ public class CalendarSyncManager extends SyncManager {
             App.log.warning("Received multiple VCALs, using first one");
 
         Event event = events[0];
+        LocalEvent local = (LocalEvent) localCollection.getByUid(event.uid);
 
         if (cEntry.isAction(SyncEntry.Actions.ADD) || cEntry.isAction(SyncEntry.Actions.CHANGE)) {
-            LocalResource local = processEvent(event);
+            processEvent(event, local);
-
-            if (local != null) {
-                localResources.put(local.getUuid(), local);
-            }
-
         } else {
-            LocalResource local = localResources.get(event.uid);
             App.log.info("Removing local record #" + local.getId() + " which has been deleted on the server");
-            localResources.remove(local.getUuid());
             local.delete();
         }
     }
 
-    private LocalResource processEvent(final Event newData) throws IOException, ContactsStorageException, CalendarStorageException {
+    private LocalResource processEvent(final Event newData, LocalEvent localEvent) throws IOException, ContactsStorageException, CalendarStorageException {
         // delete local event, if it exists
-        LocalEvent localEvent = (LocalEvent) localResources.get(newData.uid);
         if (localEvent != null) {
             App.log.info("Updating " + newData.uid + " in local calendar");
             localEvent.setETag(newData.uid);

app/src/main/java/at/bitfire/davdroid/syncadapter/ContactsSyncManager.java

@@ -149,26 +149,20 @@ public class ContactsSyncManager extends SyncManager {
             App.log.warning("Received multiple VCards, using first one");
 
         Contact contact = contacts[0];
+        LocalResource local = (LocalResource) localCollection.getByUid(contact.uid);
+
 
         if (cEntry.isAction(SyncEntry.Actions.ADD) || cEntry.isAction(SyncEntry.Actions.CHANGE)) {
-            LocalResource local = processContact(contact);
+            processContact(contact, local);
-
-            if (local != null) {
-                localResources.put(local.getUuid(), local);
-            }
-
         } else {
-            LocalResource local = localResources.get(contact.uid);
             App.log.info("Removing local record #" + local.getId() + " which has been deleted on the server");
-            localResources.remove(local.getUuid());
             local.delete();
         }
     }
 
-    private LocalResource processContact(final Contact newData) throws IOException, ContactsStorageException {
+    private LocalResource processContact(final Contact newData, LocalResource local) throws IOException, ContactsStorageException {
         String uuid = newData.uid;
         // update local contact, if it exists
-        LocalResource local = localResources.get(uuid);
         if (local != null) {
             App.log.log(Level.INFO, "Updating " + uuid + " in local address book", newData);
 

app/src/main/java/at/bitfire/davdroid/syncadapter/SyncManager.java

@@ -92,11 +92,6 @@ abstract public class SyncManager {
      */
     protected List<JournalEntryManager.Entry> remoteEntries;
 
-    /**
-     * sync-able resources in the local collection, as enumerated by {@link #prepareLocal()}
-     */
-    protected Map<String, LocalResource> localResources;
-
     public SyncManager(Context context, Account account, AccountSettings settings, Bundle extras, String authority, SyncResult syncResult, String uniqueCollectionId, CollectionInfo.Type serviceType) throws InvalidAccountException {
         this.context = context;
         this.account = account;
@@ -311,19 +306,10 @@ abstract public class SyncManager {
     }
 
     /**
-     * Lists all local resources which should be taken into account for synchronization into {@link #localResources}.
      */
     protected void prepareLocal() throws CalendarStorageException, ContactsStorageException {
         prepareDirty();
 
-        // fetch list of local contacts and build hash table to index file name
-        LocalResource[] localList = localCollection.getAll();
-        localResources = new HashMap<>(localList.length);
-        for (LocalResource resource : localList) {
-            App.log.fine("Found local resource: " + resource.getUuid());
-            localResources.put(resource.getUuid(), resource);
-        }
-
         remoteCTag = localCollection.getCTag();
     }