Htykuut

I am working on file scanner App and clear cache it is crash on activity . my application has clear cache like boost application, unstall apk from app Ram boost etc ........

 private void travelPath(File root, int level) {

    if (root == null || !root.exists() || level > SCAN_LEVEL) {

        return;

    }



    File lists = root.listFiles();

    for (File file : lists) {

        if (file.isFile()) {

            String name = file.getName();

            JunkInfo info = null;

            if (name.endsWith(".apk")) {

                info = new JunkInfo();

                info.mSize = file.length();

                info.name = name;

                info.mPath = file.getAbsolutePath();

                info.mIsChild = false;

                info.mIsVisible = true;

                mApkInfo.mChildren.add(info);

                mApkInfo.mSize += info.mSize;

            } else if (name.endsWith(".log")) {

                info = new JunkInfo();

                info.mSize = file.length();

                info.name = name;

                info.mPath = file.getAbsolutePath();

                info.mIsChild = false;

                info.mIsVisible = true;

                mLogInfo.mChildren.add(info);

                mLogInfo.mSize += info.mSize;

            } else if (name.endsWith(".tmp") || name.endsWith(".temp")) {

                info = new JunkInfo();

                info.mSize = file.length();

                info.name = name;

                info.mPath = file.getAbsolutePath();

                info.mIsChild = false;

                info.mIsVisible = true;

                mTmpInfo.mChildren.add(info);

                mTmpInfo.mSize += info.mSize;

            }



            if (info != null) {

                mCallback.onProgress(info);

            }

        } else {

            if (level < SCAN_LEVEL) {

                travelPath(file, level + 1);

            }

        }

    }

}

and LogCat error is :

 java.lang.RuntimeException: An error occurred while executing doInBackground()

    at android.os.AsyncTask$3.done(AsyncTask.java:353)

    at java.util.concurrent.FutureTask.finishCompletion(FutureTask.java:383)

    at java.util.concurrent.FutureTask.setException(FutureTask.java:252)

    at java.util.concurrent.FutureTask.run(FutureTask.java:271)

    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:245)

    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162)

    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636)

    at java.lang.Thread.run(Thread.java:764)

 Caused by: java.lang.NullPointerException: Attempt to get length of null array

    at com.example.dell.testnew.custom.OverallScanTask.travelPath(OverallScanTask.java:35)

    at com.example.dell.testnew.custom.OverallScanTask.doInBackground(OverallScanTask.java:85)

    at com.example.dell.testnew.custom.OverallScanTask.doInBackground(OverallScanTask.java:15)

    at android.os.AsyncTask$2.call(AsyncTask.java:333)

    at java.util.concurrent.FutureTask.run(FutureTask.java:266)

    at android.os.AsyncTask$SerialExecutor$1.run(AsyncTask.java:245) 

    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1162) 

    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:636) 

    at java.lang.Thread.run(Thread.java:764) 



 Caused by: java.lang.NullPointerException: Attempt to get length of null array

    at com.example.dell.testnew.custom.OverallScanTask.travelPath(OverallScanTask.java:35)

    at com.example.dell.testnew.custom.OverallScanTask.doInBackground(OverallScanTask.java:85)

    at com.example.dell.testnew.custom.OverallScanTask.doInBackground(OverallScanTask.java:15)

    at android.os.AsyncTask$2.call(AsyncTask.java:333)

getting error here for loop for a file scanner

Thank you in Advance for help i will appreciate your answer

Files.listFiles can return null if it is not a directory:

Returns an array of abstract pathnames denoting the files and directories in
the directory denoted by this abstract pathname. The array will be
empty if the directory is empty. Returns null if this abstract
pathname does not denote a directory, or if an I/O error occurs.

If you do not expect it to be null, then you should probably revisit your code logic and find a workaround, otherwise you can easily handle it with a null check.