return a CursorList from ManyQuery which lazily instantiates models f…

…rom the cursor
emilsjolander · Nov 28, 2013 · c028449 · c028449
1 parent d246228
commit c028449
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Showing 4 changed files with 109 additions and 37 deletions.
diff --git a/gradle.properties b/gradle.properties
@@ -1,4 +1,4 @@
-VERSION_NAME=0.1.0
+VERSION_NAME=0.1.1
 GROUP=se.emilsjolander
 
 POM_DESCRIPTION=Sprinkles is a boiler-plate-reduction-library for dealing with databases in android applications

diff --git a/library/src/se/emilsjolander/sprinkles/CursorIterator.java b/library/src/se/emilsjolander/sprinkles/CursorIterator.java
@@ -0,0 +1,39 @@
+package se.emilsjolander.sprinkles;
+
+import android.database.Cursor;
+
+import java.util.Iterator;
+
+/**
+ * Created by emilsjolander on 28/11/13.
+ */
+public class CursorIterator<T extends Model> implements Iterator<T> {
+
+    private Cursor cursor;
+    private Class<T> type;
+    private int pos = -1;
+
+    CursorIterator(Cursor cursor, Class<T> type) {
+        this.cursor = cursor;
+        this.type = type;
+    }
+
+    @Override
+    public boolean hasNext() {
+        cursor.moveToPosition(pos);
+        return !cursor.isLast();
+    }
+
+    @Override
+    public T next() {
+        pos++;
+        cursor.moveToPosition(pos);
+        return Utils.getModelFromCursor(type, cursor);
+    }
+
+    @Override
+    public void remove() {
+        throw new UnsupportedOperationException();
+    }
+
+}
diff --git a/...se/emilsjolander/sprinkles/ModelList.java → ...e/emilsjolander/sprinkles/CursorList.java b/...se/emilsjolander/sprinkles/ModelList.java → ...e/emilsjolander/sprinkles/CursorList.java
@@ -1,22 +1,62 @@
 package se.emilsjolander.sprinkles;
 
-import java.util.ArrayList;
-
+import android.database.Cursor;
 import android.os.AsyncTask;
 
-public class ModelList<T extends Model> extends ArrayList<T> {
+import java.io.Closeable;
+import java.io.IOException;
+import java.util.Iterator;
+
+public class CursorList<T extends Model> implements Iterable<T>, Closeable {
 
 	private static final long serialVersionUID = 9111033070491580889L;
 
-	public interface OnAllSavedCallback {
+    public interface OnAllSavedCallback {
 		void onAllSaved();
 	}
 
 	public interface OnAllDeletedCallback {
 		void onAllDeleted();
 	}
 
-	public boolean saveAll() {
+    private Cursor cursor;
+    private Class<T> type;
+    private boolean closed;
+
+    CursorList(Cursor cursor, Class<T> type) {
+        this.cursor = cursor;
+        this.type = type;
+    }
+
+    public int size() {
+        return cursor == null ? 0 : cursor.getCount();
+    }
+
+    public T get(int pos) {
+        requireOpen();
+        cursor.moveToPosition(pos);
+        return Utils.getModelFromCursor(type, cursor);
+    }
+
+    @Override
+    public Iterator<T> iterator() {
+        return new CursorIterator(cursor, type);
+    }
+
+    @Override
+    public void close() throws IOException {
+        cursor.close();
+        closed = true;
+    }
+
+    private void requireOpen() {
+        if (closed) {
+            throw new IllegalStateException("Cannot call methods on a closed CursorList");
+        }
+    }
+
+    public boolean saveAll() {
+        requireOpen();
 		Transaction t = new Transaction();
 		try {
 			t.setSuccessful(saveAll(t));
@@ -27,6 +67,7 @@ public boolean saveAll() {
 	}
 
 	public boolean saveAll(Transaction t) {
+        requireOpen();
 		for (Model m : this) {
 			if (!m.save(t)) {
 				return false;
@@ -36,10 +77,12 @@ public boolean saveAll(Transaction t) {
 	}
 
 	public void saveAllAsync() {
+        requireOpen();
 		saveAllAsync(null);
 	}
 
 	public void saveAllAsync(final OnAllSavedCallback callback) {
+        requireOpen();
 		new AsyncTask<Void, Void, Boolean>() {
 
 			protected Boolean doInBackground(Void... params) {
@@ -56,6 +99,7 @@ protected void onPostExecute(Boolean result) {
 	}
 
 	public void deleteAll() {
+        requireOpen();
 		Transaction t = new Transaction();
 		try {
 			deleteAll(t);
@@ -66,16 +110,19 @@ public void deleteAll() {
 	}
 
 	public void deleteAll(Transaction t) {
+        requireOpen();
 		for (Model m : this) {
 			m.delete(t);
 		}
 	}
 
 	public void deleteAllAsync() {
+        requireOpen();
 		deleteAllAsync(null);
 	}
 
 	public void deleteAllAsync(final OnAllDeletedCallback callback) {
+        requireOpen();
 		new AsyncTask<Void, Void, Void>() {
 
 			protected Void doInBackground(Void... params) {

diff --git a/library/src/se/emilsjolander/sprinkles/ManyQuery.java b/library/src/se/emilsjolander/sprinkles/ManyQuery.java
@@ -1,15 +1,14 @@
 package se.emilsjolander.sprinkles;
 
-import java.util.List;
-
-import se.emilsjolander.sprinkles.Query.OnQueryResultHandler;
 import android.app.LoaderManager;
 import android.app.LoaderManager.LoaderCallbacks;
 import android.content.Loader;
 import android.database.Cursor;
 import android.database.sqlite.SQLiteDatabase;
 import android.os.Bundle;
 
+import se.emilsjolander.sprinkles.Query.OnQueryResultHandler;
+
 public final class ManyQuery<T extends Model> {
 
 	Class<T> resultClass;
@@ -18,27 +17,20 @@ public final class ManyQuery<T extends Model> {
 	ManyQuery() {
 	}
 
-	public List<T> get() {
+	public CursorList<T> get() {
 		final SQLiteDatabase db = DbOpenHelper.getInstance();
 		final Cursor c = db.rawQuery(sqlQuery, null);
-
-		ModelList<T> result = new ModelList<T>();
-		while (c.moveToNext()) {
-			result.add(Utils.getModelFromCursor(resultClass, c));
-		}
-
-		c.close();
-		return result;
+		return new CursorList<T>(c, resultClass);
 	}
 
-	public void getAsync(LoaderManager lm, OnQueryResultHandler<List<T>> handler) {
+	public void getAsync(LoaderManager lm, OnQueryResultHandler<CursorList<T>> handler) {
 		final int loaderId = sqlQuery.hashCode();
 		lm.initLoader(loaderId, null,
 				getLoaderCallbacks(sqlQuery, resultClass, handler, false, null));
 	}
 
 	public void getAsyncWithUpdates(LoaderManager lm,
-			OnQueryResultHandler<List<T>> handler,
+			OnQueryResultHandler<CursorList<T>> handler,
 			Class<?>... respondsToUpdatedOf) {
 		final int loaderId = sqlQuery.hashCode();
 		lm.initLoader(
@@ -52,24 +44,19 @@ public void getAsyncWithUpdates(LoaderManager lm,
 
 	private LoaderCallbacks<Cursor> getLoaderCallbacks(final String sqlQuery,
 			final Class<T> resultClass,
-			final OnQueryResultHandler<List<T>> handler,
+			final OnQueryResultHandler<CursorList<T>> handler,
 			final boolean getUpdates,
 			final Class<? extends Model>[] respondsToUpdatedOf) {
 		return new LoaderCallbacks<Cursor>() {
 
 			@Override
 			public void onLoaderReset(Loader<Cursor> arg0) {
-				handler.onResult(new ModelList<T>());
+				handler.onResult(new CursorList<T>(null, null));
 			}
 
 			@Override
 			public void onLoadFinished(Loader<Cursor> loader, Cursor c) {
-				ModelList<T> result = new ModelList<T>();
-				while (c.moveToNext()) {
-					result.add(Utils.getModelFromCursor(resultClass, c));
-				}
-				handler.onResult(result);
-
+				handler.onResult(new CursorList<T>(c, resultClass));
 				if (!getUpdates) {
 					loader.abandon();
 				}
@@ -84,7 +71,7 @@ public Loader<Cursor> onCreateLoader(int id, Bundle args) {
 	}
 
 	public void getAsync(android.support.v4.app.LoaderManager lm,
-			OnQueryResultHandler<List<T>> handler) {
+			OnQueryResultHandler<CursorList<T>> handler) {
 		final int loaderId = sqlQuery.hashCode();
 		lm.initLoader(
 				loaderId,
@@ -94,7 +81,7 @@ public void getAsync(android.support.v4.app.LoaderManager lm,
 	}
 
 	public void getAsyncWithUpdates(android.support.v4.app.LoaderManager lm,
-			OnQueryResultHandler<List<T>> handler,
+			OnQueryResultHandler<CursorList<T>> handler,
 			Class<?>... respondsToUpdatedOf) {
 		final int loaderId = sqlQuery.hashCode();
 		lm.initLoader(
@@ -108,25 +95,24 @@ public void getAsyncWithUpdates(android.support.v4.app.LoaderManager lm,
 
 	private android.support.v4.app.LoaderManager.LoaderCallbacks<Cursor> getSupportLoaderCallbacks(
 			final String sqlQuery, final Class<T> resultClass,
-			final OnQueryResultHandler<List<T>> handler,
+			final OnQueryResultHandler<CursorList<T>> handler,
 			final boolean getUpdates,
 			final Class<? extends Model>[] respondsToUpdatedOf) {
 		return new android.support.v4.app.LoaderManager.LoaderCallbacks<Cursor>() {
 
 			@Override
 			public void onLoaderReset(
 					android.support.v4.content.Loader<Cursor> arg0) {
-				handler.onResult(new ModelList<T>());
+				handler.onResult(new CursorList<T>(null, null));
 			}
 
 			@Override
 			public void onLoadFinished(
 					android.support.v4.content.Loader<Cursor> loader, Cursor c) {
-				ModelList<T> result = new ModelList<T>();
-				while (c.moveToNext()) {
-					result.add(Utils.getModelFromCursor(resultClass, c));
-				}
-				handler.onResult(result);
+                handler.onResult(new CursorList<T>(c, resultClass));
+                if (!getUpdates) {
+                    loader.abandon();
+                }
 
 				if (!getUpdates) {
 					loader.abandon();