[Refactor] Fix creating logger in a remote service

In a remote service, the logger behaves like Android logger.

Signed-off-by: Muntashir Al-Islam <muntashirakon@riseup.net>

app/src/main/java/io/github/muntashirakon/AppManager/logs/Log.java

@@ -37,7 +37,14 @@ public class Log extends Logger {
 
     static {
         DATE_FORMAT = new SimpleDateFormat("yyyy-MM-dd HH:mm:ss.SSS", Locale.ROOT);
-        LOG_FILE = new File(getLoggingDirectory(), "am.log");
+        File logFile;
+        try {
+            logFile = new File(getLoggingDirectory(), "am.log");
+        } catch (SecurityException e) {
+            // Remote side doesn't have a logging directory
+            logFile = null;
+        }
+        LOG_FILE = logFile;
         try {
             sInstance = new Log();
         } catch (IOException e) {

app/src/main/java/io/github/muntashirakon/AppManager/logs/Logger.java

@@ -22,15 +22,18 @@ public static File getLoggingDirectory() {
         return FileUtils.getCachePath();
     }
 
+    @Nullable
     private final PrintWriter mWriter;
 
     private boolean mIsClosed;
 
-    protected Logger(File logFile, boolean append) throws IOException {
-        mWriter = new PrintWriter(new BufferedWriter(new FileWriter(logFile, append)));
+    protected Logger(@Nullable File logFile, boolean append) throws IOException {
+        if (logFile != null) {
+            mWriter = new PrintWriter(new BufferedWriter(new FileWriter(logFile, append)));
+        } else mWriter = null;
     }
 
-    protected Logger(PrintWriter printWriter) throws IOException {
+    protected Logger(@Nullable PrintWriter printWriter) throws IOException {
         mWriter = printWriter;
     }
 
@@ -41,6 +44,10 @@ public void println(@Nullable Object message) {
 
     @CallSuper
     public void println(@Nullable Object message, @Nullable Throwable tr) {
+        if (mWriter == null) {
+            // Do nothing
+            return;
+        }
         synchronized (mWriter) {
             mWriter.println(message);
             if (tr != null) {
@@ -55,15 +62,17 @@ public void println(@Nullable Object message, @Nullable Throwable tr) {
     @CallSuper
     @Override
     public void close() {
-        mWriter.flush();
-        mWriter.close();
+        if (mWriter != null) {
+            mWriter.flush();
+            mWriter.close();
+        }
         mIsClosed = true;
     }
 
     @Override
     protected void finalize() {
         // Closing is mandatory in order to make sure the logs are written correctly
-        if (!mIsClosed) {
+        if (!mIsClosed && mWriter != null) {
             mWriter.flush();
             mWriter.close();
         }