Move Magisk Manager files into subfolder

app/src/full/java/com/topjohnwu/magisk/asyncs/ParallelTask.java

@@ -0,0 +1,39 @@
+package com.topjohnwu.magisk.asyncs;
+
+import android.app.Activity;
+import android.os.AsyncTask;
+
+import java.lang.ref.WeakReference;
+
+public abstract class ParallelTask<Params, Progress, Result> extends AsyncTask<Params, Progress, Result> {
+
+    private WeakReference<Activity> weakActivity;
+
+    private Runnable callback = null;
+
+    public ParallelTask() {}
+
+    public ParallelTask(Activity context) {
+        weakActivity = new WeakReference<>(context);
+    }
+
+    protected Activity getActivity() {
+        return weakActivity.get();
+    }
+
+    @SuppressWarnings("unchecked")
+    public ParallelTask<Params, Progress, Result> exec(Params... params) {
+        executeOnExecutor(AsyncTask.THREAD_POOL_EXECUTOR, params);
+        return this;
+    }
+
+    @Override
+    protected void onPostExecute(Result result) {
+        if (callback != null) callback.run();
+    }
+
+    public ParallelTask<Params, Progress, Result> setCallBack(Runnable next) {
+        callback = next;
+        return this;
+    }
+}