Serialize threading for download manager testing.

The download manager uses threading in a simple way -- it launches two
threads, UpdateThread and DownloadThread, and both are "fire and
forget".  This is fortunate for testing, since it means we can
eliminate multithreading and simply run each thread in order, and
everything still works.

This change does just that, abstracting Thread.start() behind
SystemFacade and making FakeSystemFacade put new threads into a queue
and then run through them serially.  This simplifies much of the test
code and makes it all much more predictable.

I've simplified the test code as much as possible here and moved a few
more tests over to PublicApiFunctionalTest, leaving only a minimum in
DownloadManagerFunctionalTest, which will eventually be deleted
altogether.  I've also improved testing in some areas -- for example,
we can now test that running notifications get cancelled after the
download completes in a robust way.

There is one test case that checks for race conditions and requires
multithreading.  I've moved this into a new ThreadingTest class, which
uses a custom FakeSystemFacade that allows multithreading.  I've
extracted AbstractPublicApiTest for the newly shared code.

Change-Id: Ic1d5c76bfa9913fe053174c3d8b516790ca8b25f

1 files changed, 110 insertions, 0 deletions

diff --git a/tests/src/com/android/providers/downloads/AbstractPublicApiTest.java b/tests/src/com/android/providers/downloads/AbstractPublicApiTest.java
new file mode 100644
index 00000000..db6b2468
--- /dev/null
+++ b/tests/src/com/android/providers/downloads/AbstractPublicApiTest.java
@@ -0,0 +1,110 @@
+/*
+ * Copyright (C) 2010 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *      http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package com.android.providers.downloads;
+
+import android.database.Cursor;
+import android.net.DownloadManager;
+import android.net.Uri;
+import android.os.ParcelFileDescriptor;
+
+import java.io.FileInputStream;
+import java.io.InputStream;
+import java.net.MalformedURLException;
+
+/**
+ * Code common to tests that use the download manager public API.
+ */
+public abstract class AbstractPublicApiTest extends AbstractDownloadManagerFunctionalTest {
+
+    class Download {
+        final long mId;
+
+        private Download(long downloadId) {
+            this.mId = downloadId;
+        }
+
+        public int getStatus() {
+            return (int) getLongField(DownloadManager.COLUMN_STATUS);
+        }
+
+        String getStringField(String field) {
+            Cursor cursor = mManager.query(new DownloadManager.Query().setFilterById(mId));
+            try {
+                assertEquals(1, cursor.getCount());
+                cursor.moveToFirst();
+                return cursor.getString(cursor.getColumnIndexOrThrow(field));
+            } finally {
+                cursor.close();
+            }
+        }
+
+        long getLongField(String field) {
+            Cursor cursor = mManager.query(new DownloadManager.Query().setFilterById(mId));
+            try {
+                assertEquals(1, cursor.getCount());
+                cursor.moveToFirst();
+                return cursor.getLong(cursor.getColumnIndexOrThrow(field));
+            } finally {
+                cursor.close();
+            }
+        }
+
+        String getContents() throws Exception {
+            ParcelFileDescriptor downloadedFile = mManager.openDownloadedFile(mId);
+            assertTrue("Invalid file descriptor: " + downloadedFile,
+                       downloadedFile.getFileDescriptor().valid());
+            InputStream stream = new FileInputStream(downloadedFile.getFileDescriptor());
+            try {
+                return readStream(stream);
+            } finally {
+                stream.close();
+            }
+        }
+
+        void runUntilStatus(int status) throws Exception {
+            runService();
+            assertEquals(status, getStatus());
+        }
+    }
+
+    protected static final String PACKAGE_NAME = "my.package.name";
+    protected static final String REQUEST_PATH = "/path";
+
+    protected DownloadManager mManager;
+
+    public AbstractPublicApiTest(FakeSystemFacade systemFacade) {
+        super(systemFacade);
+    }
+
+    @Override
+    protected void setUp() throws Exception {
+        super.setUp();
+        mManager = new DownloadManager(mResolver, PACKAGE_NAME);
+    }
+
+    protected DownloadManager.Request getRequest() throws MalformedURLException {
+        return getRequest(getServerUri(REQUEST_PATH));
+    }
+
+    protected DownloadManager.Request getRequest(String path) {
+        return new DownloadManager.Request(Uri.parse(path));
+    }
+
+    protected Download enqueueRequest(DownloadManager.Request request) {
+        return new Download(mManager.enqueue(request));
+    }
+}