EOF

gistfile1.txt

  
  READ:

  FileInputStream in = openFileInput("filename.txt");
    InputStreamReader inputStreamReader = new InputStreamReader(in);
    BufferedReader bufferedReader = new BufferedReader(inputStreamReader);
    StringBuilder sb = new StringBuilder();
    String line;
    while ((line = bufferedReader.readLine()) != null) {
        sb.append(line);
    }

---------
WRITE:

      FileOutputStream fos = openFileOutput(textOutput, Context.MODE_PRIVATE);
            fos.write(textOutput.getBytes());
            fos.close();

--------------------
Storing:  

KeyStore ks = KeyStore.getInstance("JKS");
ks.setKeyEntry("keyAlias", key, passwordForKeyCharArray, certChain);
OutputStream writeStream = new FileOutputStream(filePathToStore);
ks.store(writeStream, keystorePasswordCharArray);
writeStream.close();
Note thet certChain might be null, unless you are passing PrivateKey

-------------

Loading:

KeyStore ks = KeyStore.getInstance("JKS");
InputStream readStream = new FileInputStream(filePathToStore);
ks.load(readStream, keystorePasswordCharArray);
Key key = ks.getKey("keyAlias", passwordForKeyCharArray);
readStream.close();