Retain transitories across the api dao/content resolver boundary

api/src/com/todoroo/andlib/data/AbstractModel.java

@@ -11,6 +11,8 @@ import java.lang.reflect.Modifier;
 import java.util.ArrayList;
 import java.util.Arrays;
 import java.util.HashMap;
+import java.util.HashSet;
+import java.util.Set;
 
 import android.content.ContentValues;
 import android.os.Parcel;
@@ -48,6 +50,9 @@ public abstract class AbstractModel implements Parcelable, Cloneable {
     /** sentinel for objects without an id */
     public static final long NO_ID = 0;
 
+    /** prefix for transitories retained in content values */
+    public static final String RETAIN_TRANSITORY_PREFIX = "retain-trans-"; //$NON-NLS-1$
+
     // --- abstract methods
 
     /** Get the default values for this object */
@@ -313,6 +318,7 @@ public abstract class AbstractModel implements Parcelable, Cloneable {
     public synchronized <TYPE> void mergeWith(ContentValues other) {
         if (setValues == null)
             setValues = new ContentValues();
+        restoreTransitories(other);
         setValues.putAll(other);
     }
 
@@ -371,6 +377,74 @@ public abstract class AbstractModel implements Parcelable, Cloneable {
         return transitoryData.remove(key);
     }
 
+    /**
+     * Move transitory values (those that can be saved) to setValues,
+     * to be restored later. This is useful for the api daos that go
+     * through the content provider
+     */
+    public synchronized void retainTransitories() {
+        if (transitoryData == null)
+            return;
+        if (setValues == null)
+            setValues = new ContentValues();
+        Set<String> keys = transitoryData.keySet();
+        for (String key : keys) {
+            String newKey = RETAIN_TRANSITORY_PREFIX + key;
+            Object value = transitoryData.get(key);
+            putObjectInContentValues(newKey, value, setValues);
+        }
+    }
+
+    /**
+     * Read keys from ContentValues. Remove those that match the
+     * RETAIN_TRANSITORY_PREFIX pattern and set those values
+     * on transitory data
+     * @param cv
+     */
+    private void restoreTransitories(ContentValues cv) {
+        if (transitoryData == null)
+            transitoryData = new HashMap<String, Object>();
+        Set<String> keys = cv.keySet();
+        Set<String> keysToRemove = new HashSet<String>();
+        for (String key : keys) {
+            if (key.startsWith(RETAIN_TRANSITORY_PREFIX)) {
+                String newKey = key.substring(RETAIN_TRANSITORY_PREFIX.length());
+                Object value = cv.get(key);
+                transitoryData.put(newKey, value);
+                keysToRemove.add(key);
+            }
+        }
+
+        for (String key : keysToRemove) {
+            cv.remove(key);
+        }
+    }
+
+    /**
+     * If value is of a type that is puttable in ContentValues, cast and put it
+     * @param key
+     * @param value
+     * @param cv
+     */
+    private void putObjectInContentValues(String key, Object value, ContentValues cv) {
+        if (value instanceof Boolean)
+            cv.put(key, (Boolean) value);
+        if (value instanceof Byte)
+            cv.put(key, (Byte) value);
+        if (value instanceof Double)
+            cv.put(key, (Double) value);
+        if (value instanceof Float)
+            cv.put(key, (Float) value);
+        if (value instanceof Integer)
+            cv.put(key, (Integer) value);
+        if (value instanceof Long)
+            cv.put(key, (Long) value);
+        if (value instanceof Short)
+            cv.put(key, (Short) value);
+        if (value instanceof String)
+            cv.put(key, (String) value);
+    }
+
 
     // --- Convenience wrappers for using transitories as flags
     public boolean checkTransitory(String flag) {

api/src/com/todoroo/andlib/data/ContentResolverDao.java

@@ -91,12 +91,17 @@ public class ContentResolverDao<TYPE extends AbstractModel> {
      * @return true if data was written to the db, false otherwise
      */
     public boolean save(TYPE model) {
+        boolean retainedTransitories = false;
         if(model.isSaved()) {
             if(model.getSetValues() == null)
                 return false;
+            model.retainTransitories();
+            retainedTransitories = true;
             if(cr.update(uriWithId(model.getId()), model.getSetValues(), null, null) != 0)
                 return true;
         }
+        if (!retainedTransitories)
+            model.retainTransitories();
         Uri uri = cr.insert(baseUri, model.getMergedValues());
         long id = Long.parseLong(uri.getLastPathSegment());
         model.setId(id);