feat: benchmark MediaStore API of Android

app/src/main/AndroidManifest.xml

@@ -6,6 +6,9 @@
     <uses-permission android:name="android.permission.FOREGROUND_SERVICE_MEDIA_PLAYBACK" />
     <uses-permission android:name="android.permission.WAKE_LOCK" />
 
+    <uses-permission android:name="android.permission.READ_EXTERNAL_STORAGE" />
+    <uses-permission android:name="android.permission.READ_MEDIA_AUDIO" />
+
     <application
         android:allowBackup="true"
         android:dataExtractionRules="@xml/data_extraction_rules"
@@ -23,7 +26,14 @@
             android:theme="@style/Theme.Lockstep">
             <intent-filter>
                 <action android:name="android.intent.action.MAIN" />
-
+                <category android:name="android.intent.category.LAUNCHER" />
+            </intent-filter>
+        </activity>
+        <activity
+            android:name="at.lockstep.app.MediaStoreBenchmarkActivity"
+            android:exported="true">
+            <intent-filter>
+                <action android:name="android.intent.action.MAIN" />
                 <category android:name="android.intent.category.LAUNCHER" />
             </intent-filter>
         </activity>

app/src/main/java/at/lockstep/app/MainActivity.java

@@ -1,6 +1,7 @@
 package at.lockstep.app;
 
 import android.app.Activity;
+import android.content.Intent;
 import android.os.Bundle;
 import android.widget.Button;
 
@@ -12,6 +13,7 @@ import at.lockstep.pb.PlaybackEngine;
 public class MainActivity extends Activity {
     private Button btnStart;
     private Button btnStop;
+    private Button btnMediaStoreBenchmark;
 
     @Override
     protected void onCreate(Bundle savedInstanceState) {
@@ -20,6 +22,7 @@ public class MainActivity extends Activity {
 
         btnStart = findViewById(R.id.btnStart);
         btnStop = findViewById(R.id.btnStop);
+        btnMediaStoreBenchmark = findViewById(R.id.btnMediaStoreBenchmark);
 
         // TODO: handle clicking START button twice
         btnStart.setOnClickListener(v ->
@@ -39,5 +42,10 @@ public class MainActivity extends Activity {
         btnStop.setOnClickListener(v ->
                 startService(LstForegroundService.stopIntent(MainActivity.this))
         );
+
+        btnMediaStoreBenchmark.setOnClickListener(v -> {
+            Intent intent = new Intent(MainActivity.this, MediaStoreBenchmarkActivity.class);
+            startActivity(intent);
+        });
     }
 }

app/src/main/java/at/lockstep/app/MediaStoreBenchmarkActivity.java

@@ -0,0 +1,141 @@
+package at.lockstep.app;
+
+import static androidx.activity.result.ActivityResultCallerKt.registerForActivityResult;
+
+import android.app.Activity;
+
+import android.Manifest;
+import android.content.pm.PackageManager;
+import android.os.Build;
+import android.os.Bundle;
+import android.os.SystemClock;
+import android.provider.MediaStore;
+import android.widget.TextView;
+
+import androidx.activity.result.ActivityResultLauncher;
+import androidx.activity.result.contract.ActivityResultContracts;
+import androidx.core.content.ContextCompat;
+
+import java.util.ArrayList;
+import java.util.List;
+
+import at.lockstep.R;
+
+public class MediaStoreBenchmarkActivity extends Activity {
+
+    private TextView resultTextView;
+
+    @Override
+    protected void onCreate(Bundle savedInstanceState) {
+        super.onCreate(savedInstanceState);
+        setContentView(R.layout.activity_media_store_benchmark);
+
+        resultTextView = findViewById(R.id.resultTextView);
+
+        if (hasReadPermission()) {
+            loadMusic();
+        } else {
+            requestReadPermission();
+        }
+    }
+
+    private static final int REQUEST_READ_PERMISSION = 1001;
+
+    @Override
+    public void onRequestPermissionsResult(
+            int requestCode,
+            String[] permissions,
+            int[] grantResults
+    ) {
+        super.onRequestPermissionsResult(requestCode, permissions, grantResults);
+
+        if (requestCode == REQUEST_READ_PERMISSION) {
+            boolean granted = grantResults.length > 0
+                    && grantResults[0] == PackageManager.PERMISSION_GRANTED;
+
+            if (granted) {
+                loadMusic();
+            } else {
+                resultTextView.setText("Permission denied.");
+            }
+        }
+    }
+
+    private boolean hasReadPermission() {
+        String permission;
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+            permission = Manifest.permission.READ_MEDIA_AUDIO;
+        } else {
+            permission = Manifest.permission.READ_EXTERNAL_STORAGE;
+        }
+
+        return ContextCompat.checkSelfPermission(this, permission)
+                == PackageManager.PERMISSION_GRANTED;
+    }
+
+    private void requestReadPermission() {
+        String permission;
+        if (Build.VERSION.SDK_INT >= Build.VERSION_CODES.TIRAMISU) {
+            permission = Manifest.permission.READ_MEDIA_AUDIO;
+        } else {
+            permission = Manifest.permission.READ_EXTERNAL_STORAGE;
+        }
+
+        //permissionLauncher.launch(permission);
+        requestPermissions(
+                new String[]{ permission },
+                REQUEST_READ_PERMISSION
+        );
+    }
+
+    private void loadMusic() {
+        List<String> musicList = new ArrayList<>();
+
+        android.net.Uri collection = MediaStore.Audio.Media.EXTERNAL_CONTENT_URI;
+
+        String[] projection = new String[] {
+                MediaStore.Audio.Media._ID,
+                MediaStore.Audio.Media.TITLE,
+                MediaStore.Audio.Media.DATA
+        };
+
+        String selection = MediaStore.Audio.Media.IS_MUSIC + " != 0";
+
+        long start = SystemClock.elapsedRealtime();
+
+        try (android.database.Cursor cursor = getContentResolver().query(
+                collection,
+                projection,
+                selection,
+                null,
+                MediaStore.Audio.Media.TITLE + " ASC"
+        )) {
+            if (cursor != null) {
+                int titleColumn = cursor.getColumnIndexOrThrow(MediaStore.Audio.Media.TITLE);
+                int dataColumn = cursor.getColumnIndex(MediaStore.Audio.Media.DATA);
+
+                while (cursor.moveToNext()) {
+                    String title = cursor.getString(titleColumn);
+                    String path = dataColumn != -1 ? cursor.getString(dataColumn) : null;
+
+                    if (path != null) {
+                        musicList.add(title + "\n" + path);
+                    } else {
+                        musicList.add(title + "\n[path unavailable]");
+                    }
+                }
+            }
+        }
+
+        long elapsedMs = SystemClock.elapsedRealtime() - start;
+
+        StringBuilder header = new StringBuilder();
+        header.append("Found ").append(musicList.size()).append(" music files\n");
+        header.append("Query time: ").append(elapsedMs).append(" ms\n\n");
+
+        resultTextView.setText(header.toString() + String.join("\n\n", musicList));
+
+        // 200 music files in 32 ms
+        // paths like "/storage/emulated/0/Download/...mp3"
+    }
+}

app/src/main/res/layout/activity_main.xml

@@ -18,4 +18,10 @@
         android:layout_height="wrap_content"
         android:layout_marginTop="16dp"
         android:text="Stop collection" />
+
+    <Button
+        android:id="@+id/btnMediaStoreBenchmark"
+        android:layout_width="wrap_content"
+        android:layout_height="wrap_content"
+        android:text="Benchmark media store" />
 </LinearLayout>

app/src/main/res/layout/activity_media_store_benchmark.xml

@@ -0,0 +1,13 @@
+<?xml version="1.0" encoding="utf-8"?>
+<ScrollView xmlns:android="http://schemas.android.com/apk/res/android"
+    android:layout_width="match_parent"
+    android:layout_height="match_parent">
+
+    <TextView
+        android:id="@+id/resultTextView"
+        android:layout_width="match_parent"
+        android:layout_height="wrap_content"
+        android:padding="16dp"
+        android:text="Loading..."
+        android:textSize="14sp" />
+</ScrollView>