I am creating an application where i do some real-time image analysis and store them into a csv file. The csv has 2 columns time and y-value of each frame.
I want to read this file and store the values from 2 columns into to double array. I want this because i want to perform an fast Fourier transformation on the data.
public class MainActivity extends AppCompatActivity implements CameraView.PreviewReadyCallback {
private static Camera camera = null;
private CameraView image = null;
private LineChart bp_graph;
private int img_Y_Avg, img_U_Avg, img_V_Avg;
private long end = 0, begin = 0;
double valueY, valueU, valueV;
Handler handler;
private int readingRemaining = 1200;
private static long time1, time2, timeDifference;
#Override
protected void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.activity_main);
getWindow().addFlags(WindowManager.LayoutParams.FLAG_KEEP_SCREEN_ON);
bp_graph = (LineChart)findViewById(R.id.graph);
graph_features();
//open camera
try {
camera = Camera.open();
handler = new Handler();
final Runnable runnable = new Runnable() {
#Override
public void run() {
camera.stopPreview();
camera.release();
}
};
handler.postDelayed(runnable, 30000);
} catch (Exception e) {
Log.d("ERROR", "Failed to get camera: " + e.getMessage());
}
if (camera != null) {
image = new CameraView(this, camera);
FrameLayout camera_view = (FrameLayout) findViewById(R.id.camera_view);
camera_view.addView(image);
image.setOnPreviewReady(this);
}
}
#Override
protected void onResume(){
super.onResume();
}
#Override
protected void onPause() {
super.onPause();
}
#Override
public void onPreviewFrame(long startTime, int ySum, int uSum, int vSum, long endTime) {
begin = startTime;
img_Y_Avg = ySum;
img_U_Avg = uSum;
img_V_Avg = vSum;
end = endTime;
showResults(begin, img_Y_Avg, img_U_Avg, img_V_Avg, end);
}
private void showResults(long startTime, int ySum, int uSum, int vSum, long endTime){
//set value of Y on the text view
TextView valueOfY = (TextView)findViewById(R.id.valueY);
//valueY = img_Y_Avg;
valueOfY.setText(String.valueOf(img_Y_Avg));
//start time in milliseconds
long StartDurationInMs = TimeUnit.MILLISECONDS.convert(begin, TimeUnit.MILLISECONDS);
ArrayList<Long> startOfTime = new ArrayList<>();
startOfTime.add(StartDurationInMs);
//store value to array list
ArrayList<Integer> yAverage = new ArrayList<>();
yAverage.add(img_Y_Avg);
//convert to readable format
String readableDate = new SimpleDateFormat("MMM dd,yyyy, HH:mm:ss.SSS").format(EndDurationInMs);
Log.d("Date ", readableDate);
Log.d("time ", String.valueOf(String.valueOf(yAverage.size())));
//store when all array are generated
Log.d("time ", String.valueOf(StartDurationInMs));
ArrayList<Long> getValues = new ArrayList<>();
for(int i = 0; i < yAverage.size(); i++) {
getValues.add(startOfTime.get(i));
getValues.add((long)(yAverage.get(i)));
}
//store the yAverage and start time to csv file
storeCsv(yAverage, getValues);
Log.d("MyEntryData", String.valueOf(getValues));
}
public void storeCsv(ArrayList<Integer>yAverage, ArrayList<Long>getValues){
String filename = "temporary.csv";
//File directoryDownload = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_DOWNLOADS);
String path = Environment.getExternalStorageDirectory().getAbsolutePath() + "/bpReader";
//File logDir = new File (directoryDownload, "bpReader"); //Creates a new folder in DOWNLOAD directory
File logDir = new File(path);
logDir.mkdirs();
File file = new File(logDir, filename);
FileOutputStream outputStream = null;
try {
file.createNewFile();
outputStream = new FileOutputStream(file, true);
//outputStream = openFileOutput(filename, Context.MODE_PRIVATE);
for (int i = 0; i < yAverage.size(); i += 2) {
outputStream.write((getValues.get(i) + ",").getBytes());
outputStream.write((getValues.get(i + 1) + "\n").getBytes());
//outputStream.write((getValues.get(i + 2) + ",").getBytes());
//outputStream.write((getValues.get(i + 3) + "\n").getBytes());
}
outputStream.flush();
outputStream.close();
} catch (Exception e) {
e.printStackTrace();
}
}
public void readCsv(){
}
}
This is my MainActivity. What I am doing here is getting the data from CameraView class for each frame with the help of an interface that I created. After that im storing the values into a CSV file called temporary.csv.
Issues
I want to read this csv and store the first column(the time) into one double array and the second column(yAverage) into another double array.
I also want to delete the file once i have all the data stored into the into the double array.
How can I do that?
I would suggest youto use an open source library like OpenCSV to get the datafrom the CSV file. When you have the library implemented it's only a matter of iterating through the x and y columns and assign them to an array. With OpenCSV it would look like that. But i would also suggest you an more object orientec approach if the x and y with the same index coords are related to each other.
String csvFile = "/Users/mkyong/csv/country3.csv";
int length = 100; //If you dont know how many entries the csv file has i would suggest to use ArrayList
double[] xCoords = new double[length];
double[] yCoords = new double[length];
CSVReader reader = null;
try {
reader = new CSVReader(new FileReader(csvFile));
String[] line;
int i = 0;
while ((line = reader.readNext()) != null) {
xCoords[i] = Double.parseDouble(line[0]);
yCoords[i] = Double.parseDouble(line[1]);
}
} catch (IOException e) {
e.printStackTrace();
}
From the answer given by Lucas, I got the direction to my solution
public void readCsv(){
//set the path to the file
String getPath = Environment.getExternalStorageDirectory() + "/bpReader";
String csvFile = "temporary.csv";
String path = getPath+ "/" + csvFile;
//File file = new File(path, csvFile);
int length = 500;
double[] xCoords = new double[length];
double[] yCoords = new double[length];
CSVReader reader = null;
try {
File myFile = new File (path);
reader = new CSVReader(new FileReader(myFile));
String[] line;
int i = 0;
while ((line = reader.readNext()) != null) {
xCoords[i] = Double.parseDouble(line[0]) ;
yCoords[i] = Double.parseDouble(line[1]);
Log.d("read:: ", "Time: "+String.valueOf(xCoords[i])+" Y: "+String.valueOf(yCoords[i]));
}
myFile.delete();
} catch (IOException e) {
e.printStackTrace();
}
}
And then i had to add
// https://mvnrepository.com/artifact/org.apache.commons/commons-lang3
compile group: 'org.apache.commons', name: 'commons-lang3', version: '3.6'
to my gradle,, which can be found at MVN repository
Related
I'm splitting an encrypted video into 4 parts using this code
public class SplitVideoFile {
private static String result;
static ArrayList<String>update=new ArrayList<>();
public static String main(File file) {
try {
// File file = new File("C:/Documents/Despicable Me 2 - Trailer (HD) - YouTube.mp4");//File read from Source folder to Split.
if (file.exists()) {
String videoFileName = file.getName().substring(0, file.getName().lastIndexOf(".")); // Name of the videoFile without extension
// String path = Environment.getDataDirectory().getAbsolutePath().toString() + "/storage/emulated/0/Videointegrity";
String path = "/storage/emulated/0/Videointegrity";
// File myDir = new File(getFile, "folder");
//myDir.mkdir();
File splitFile = new File(path.concat("/").concat(videoFileName));//Destination folder to save.
if (!splitFile.exists()) {
splitFile.mkdirs();
Log.d("Directory Created -> ", splitFile.getAbsolutePath());
}
int i = 01;// Files count starts from 1
InputStream inputStream = new FileInputStream(file);
String videoFile = splitFile.getAbsolutePath() +"/"+ String.format("%02d", i) +"_"+ file.getName();// Location to save the files which are Split from the original file.
OutputStream outputStream = new FileOutputStream(videoFile);
Log.d("File Created Location: ", videoFile);
update.add("File Created Location: ".concat(videoFile));
int totalPartsToSplit =4 ;// Total files to split.
int splitSize = inputStream.available() / totalPartsToSplit;
int streamSize = 0;
int read = 0;
while ((read = inputStream.read()) != -1) {
if (splitSize == streamSize) {
if (i != totalPartsToSplit) {
i++;
String fileCount = String.format("%02d", i); // output will be 1 is 01, 2 is 02
videoFile = splitFile.getAbsolutePath() +"/"+ fileCount +"_"+ file.getName();
outputStream = new FileOutputStream(videoFile);
Log.d("File Created Location: ", videoFile);
streamSize = 0;
}
}
outputStream.write(read);
streamSize++;
}
inputStream.close();
outputStream.close();
Log.d("Total files Split ->", String.valueOf(totalPartsToSplit));
result="success";
} else {
System.err.println(file.getAbsolutePath() +" File Not Found.");
result="failed";
}
} catch (Exception e) {
e.printStackTrace();
}
return result;
}
public ArrayList<String> getUpdate()
{
return update;
}
And in my activity file i call this using async task's doinbackground method like below
protected String doInBackground(Void...arg0) {
Log.d(TAG + " DoINBackGround", "On doInBackground...");
File encvideo=new File(epath.getText().toString());
SplitVideoFile split=new SplitVideoFile();
String result=split.main(encvideo);
publishProgress(1);
return result;
}
Even though it splits the video, it takes too much of time to do the process.
How can I speed them up. As I'm showing a progress bar in preexecute method it looks like the user sees the progress bar for a long time, which I don't want.
I am using android's thread pool executor framework (initialized as below).
BlockingQueue<Runnable> taskQueue = new LinkedBlockingQueue<>();
ExecutorService executorService = new ThreadPoolExecutor(totalCores, totalCores * 3, 10, TimeUnit.SECONDS, taskQueue);
Now, consider the following function onFrameProcessed -
public void onFrameProcessed(RenderedImage renderedImage) {
String timeNow = new SimpleDateFormat("d-M-Y_HH_mm_ss_SSS").format(new Date()).toString();
CustomRunnable3 customRunnable3 = new CustomRunnable3(renderedImage, timeNow);
executorService.execute(customRunnable3);
}
Definition of CustomRunnable3 is as follows:
class CustomRunnable3 implements Runnable {
RenderedImage renderedImageLocal;
String basePath, timeNowCopy;
int hashCode;
CustomRunnable3(RenderedImage renderedImage, String timeNow) {
renderedImageLocal = renderedImage;
this.basePath = Environment.getExternalStoragePublicDirectory(Environment.DIRECTORY_PICTURES).toString();
this.timeNowCopy = timeNow;
hashCode = renderedImageLocal.hashCode();
}
#Override
public void run() {
if (renderedImageLocal.imageType() == RenderedImage.ImageType.ThermalRadiometricKelvinImage) {
int[] thermalData = renderedImageLocal.thermalPixelValues();
String dataPath = basePath + "/" + this.timeNowCopy + ".csv";
try {
PrintWriter printWriter = new PrintWriter(dataPath);
int dataLen = thermalData.length;
for (int i = 0; i < dataLen; i++) {
printWriter.println(thermalData[i]);
}
printWriter.close();
} catch (IOException e) {
e.printStackTrace();
}
String imgPath = basePath + "/" + this.timeNowCopy + ".jpg";
try {
if (hashCode != renderedImageLocal.hashCode()) {
Log.e("Checking", "Hash code changed..");
}
renderedImageLocal.getFrame().save(new File(imgPath), frameProcessor);
if (hashCode != renderedImageLocal.hashCode()) {
Log.e("Checking", "Hash code changed after writing..");
}
} catch (IOException e) {
e.printStackTrace();
}
}
}
}
Usage Scenario : onFrameReceived is being called multiple times per second(like 4-5 times). In each call to onFrameReceived, I am saving two files from renderedImage object (1 csv file, 1 jpg file). Both of these files must be related to each other because both are created from one parent and have same name(except the extension).
Problem : But that is not happening and somehow I am ending up with jpg file content from 1 renderedImage and csv content from another renderedImage object.
What are the possible reasons for this problem, please share your opinion.
I wrote my own camera app. This app writes exif information in the jpg files. It works well but I have some problems with the exifInferface class, e.g., I get the following errors when re-read the JPG file:
Warning Invalid EXIF text encoding
Warning Invalid size (8589934590) for IFD0 tag 0x8827
Warning Bad IFD1 directory
I know that my IFD0 pointer at the exif-Information is broken. It may be that while writing the exif information the pointer is broken?
However, I've Googled and found nothing
I use this class to read an write the exif-informations:
public class ExifHelper {
private String aperature = null;
private String exposureTime = null;
private String flash = null;
private String focalLength = null;
private String gpsAltitude = null;
private String gpsAltitudeRef = null;
private String gpsDateStamp = null;
private String gpsLatitude = null;
private String gpsLatitudeRef = null;
private String gpsLongitude = null;
private String gpsLongitudeRef = null;
private String gpsProcessingMethod = null;
private String gpsTimestamp = null;
private String iso = null;
private String make = null;
private String model = null;
private String imageLength = null;
private String imageWidth = null;
private String orientation = null;
private String whiteBalance = null;
private String exifVersion = null;
private String time = null;
private ExifInterface inFile = null;
private ExifInterface outFile = null;
final static String TAG = "ExifHelper";
/**
* The file before it is compressed
*
* #param filePath
* #throws IOException
*/
public void createInFile(String filePath) throws IOException {
this.inFile = new ExifInterface(filePath);
}
/**
* The file after it has been compressed
*
* #param filePath
* #throws IOException
*/
public void createOutFile(String filePath) throws IOException {
this.outFile = new ExifInterface(filePath);
}
/**
* Reads all the EXIF data from the input file.
*/
public void readExifData() {
this.aperature = inFile.getAttribute(ExifInterface.TAG_APERTURE);
this.exposureTime = inFile.getAttribute(ExifInterface.TAG_EXPOSURE_TIME);
this.flash = inFile.getAttribute(ExifInterface.TAG_FLASH);
this.focalLength = inFile.getAttribute(ExifInterface.TAG_FOCAL_LENGTH);
this.gpsAltitude = inFile.getAttribute(ExifInterface.TAG_GPS_ALTITUDE);
this.gpsAltitudeRef = inFile.getAttribute(ExifInterface.TAG_GPS_ALTITUDE_REF);
this.gpsDateStamp = inFile.getAttribute(ExifInterface.TAG_GPS_DATESTAMP);
this.gpsLatitude = inFile.getAttribute(ExifInterface.TAG_GPS_LATITUDE);
this.gpsLatitudeRef = inFile.getAttribute(ExifInterface.TAG_GPS_LATITUDE_REF);
this.gpsLongitude = inFile.getAttribute(ExifInterface.TAG_GPS_LONGITUDE);
this.gpsLongitudeRef = inFile.getAttribute(ExifInterface.TAG_GPS_LONGITUDE_REF);
this.gpsProcessingMethod = inFile.getAttribute(ExifInterface.TAG_GPS_PROCESSING_METHOD);
this.gpsTimestamp = inFile.getAttribute(ExifInterface.TAG_GPS_TIMESTAMP);
this.imageLength = inFile.getAttribute(ExifInterface.TAG_IMAGE_LENGTH);
this.imageWidth = inFile.getAttribute(ExifInterface.TAG_IMAGE_WIDTH);
this.iso = inFile.getAttribute(ExifInterface.TAG_ISO);
this.make = inFile.getAttribute(ExifInterface.TAG_MAKE);
this.model = inFile.getAttribute(ExifInterface.TAG_MODEL);
this.orientation = inFile.getAttribute(ExifInterface.TAG_ORIENTATION);
this.whiteBalance = inFile.getAttribute(ExifInterface.TAG_WHITE_BALANCE);
this.exifVersion = inFile.getAttribute("ExifVersion");
}
/**
* Writes the previously stored EXIF data to the output file.
* #param pictureDate
* #param orientationValues
* #param accelValues
*
* #throws IOException
*/
public void writeExifData(String pictureDate) throws IOException {
// Don't try to write to a null file
if (this.outFile == null) {
return;
}
if (this.aperature != null) {
this.outFile.setAttribute(ExifInterface.TAG_APERTURE, this.aperature);
}
if (this.exposureTime != null) {
this.outFile.setAttribute(ExifInterface.TAG_EXPOSURE_TIME, this.exposureTime);
}
if (this.flash != null) {
this.outFile.setAttribute(ExifInterface.TAG_FLASH, this.flash);
}
if (this.focalLength != null) {
this.outFile.setAttribute(ExifInterface.TAG_FOCAL_LENGTH, this.focalLength);
}
if (this.gpsAltitude != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_ALTITUDE, this.gpsAltitude);
}
if (this.gpsAltitudeRef != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_ALTITUDE_REF, this.gpsAltitudeRef);
}
if (this.gpsDateStamp != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_DATESTAMP, this.gpsDateStamp);
}
if (this.gpsLatitude != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_LATITUDE, this.gpsLatitude);
}
if (this.gpsLatitudeRef != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_LATITUDE_REF, this.gpsLatitudeRef);
}
if (this.gpsLongitude != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_LONGITUDE, this.gpsLongitude);
}
if (this.gpsLongitudeRef != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_LONGITUDE_REF, this.gpsLongitudeRef);
}
if (this.gpsProcessingMethod != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_PROCESSING_METHOD, this.gpsProcessingMethod);
}
if (this.gpsTimestamp != null) {
this.outFile.setAttribute(ExifInterface.TAG_GPS_TIMESTAMP, this.gpsTimestamp);
}
if (this.iso != null) {
this.outFile.setAttribute(ExifInterface.TAG_ISO, this.iso);
}
if (this.make != null) {
this.outFile.setAttribute(ExifInterface.TAG_MAKE, this.make);
}
if (this.model != null) {
this.outFile.setAttribute(ExifInterface.TAG_MODEL, this.model);
}
if (this.orientation != null) {
this.outFile.setAttribute(ExifInterface.TAG_ORIENTATION, this.orientation);
}
if (this.whiteBalance != null) {
this.outFile.setAttribute(ExifInterface.TAG_WHITE_BALANCE, this.whiteBalance);
}
if (this.exifVersion != null) {
this.outFile.setAttribute("ExifVersion", this.exifVersion);
}
this.outFile.setAttribute(ExifInterface.TAG_IMAGE_LENGTH, this.imageLength);
this.outFile.setAttribute(ExifInterface.TAG_IMAGE_WIDTH, this.imageWidth);
this.outFile.setAttribute(ExifInterface.TAG_DATETIME, pictureDate);
String mString = exifRandomZahlen();
this.outFile.setAttribute("UserComment", mString);
this.outFile.saveAttributes();
}
I also write 2 images form the takepicture-method. One the original there is no problem and the second with modify exif informations. There is the problem with the exifinterface I think by writing it back to the JPG.
I used the tool DumpImage to view the exif informations. This tool is from the metaworking group (www.metadataworkinggroup.org)
So I have a big question, How I can fix this broken exif data? For example the IDF0 pointer
somebody know or have the same problem?
I get, for example, the Tag TAG_DATETIME two times in my exif information
this is the class for saveing the photo:
public class Photo extends Activity implements PictureCallback {
public interface OnPictureTakenListener {
void pictureTaken(File pictureFile, File pictureFilePatched, String exifDateString);
}
private final Context context;
private OnPictureTakenListener listener;
public Photo(Context ourContext, OnPictureTakenListener theListener) {
this.context = ourContext;
this.listener = theListener;
}
#SuppressLint("SimpleDateFormat")
#Override
public void onPictureTaken(byte[] data, Camera camera) {
Date date = new Date();
File pictureFileDir = getDir();
if (!pictureFileDir.exists() && !pictureFileDir.mkdirs())
{
Log.d(AndroidCamera.DEBUG_TAG,
"Can't create directory to save image.");
Toast.makeText(context, "Can't create directory to save image.",
Toast.LENGTH_LONG).show();
return;
}
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy:MM:dd HH:mm:ss");
SimpleDateFormat dateConverter = new SimpleDateFormat("yyyy_MM_dd_HH_mm_ss");
String exifDateString = dateFormat.format(date);
String datePicture = dateConverter.format(date);
String photoFile = "Picture_" + datePicture + ".jpg";
String photoFilePatched = "Picture_" + datePicture + "_patched.jpg";
String filename = pictureFileDir.getPath() + File.separator + photoFile;
String filenamePatched = pictureFileDir.getPath() + File.separator + photoFilePatched;
File pictureFile = new File(filename);
File pictureFilePatched = new File (filenamePatched);
try {
FileOutputStream fos = new FileOutputStream(pictureFile);
FileOutputStream fosPatched = new FileOutputStream(pictureFilePatched);
fos.write(data);
fosPatched.write(data);
fos.close();
fosPatched.close();
Toast.makeText(context, "New Image saved:" + photoFile,
Toast.LENGTH_LONG).show();
} catch (Exception error) {
Log.d(AndroidCamera.DEBUG_TAG, "File" + filename + " not saved: "
+ error.getMessage());
Toast.makeText(context, "Image could not be saved.",
Toast.LENGTH_LONG).show();
}
listener.pictureTaken(pictureFile,pictureFilePatched,exifDateString);
context.sendBroadcast(new Intent(Intent.ACTION_MEDIA_MOUNTED, Uri.parse("file://"+ Environment.getExternalStorageDirectory())));
}
private File getDir() {
File sdDir = Environment
.getExternalStoragePublicDirectory(Environment.DIRECTORY_DCIM);
return new File(sdDir, "Camera");
}
static final int REQUEST_IMAGE_CAPTURE = 1;
}
here in main activity i call on one from the two pictures to write the exif infortmations:
camera.takePicture(null, null, new Photo(this,
new Photo.OnPictureTakenListener() {
public void pictureTaken(final File pictureFile,final File pictureFilePatched , final String date) {
final String fileName = pictureFile.getPath();
final String fileNamePatched = pictureFilePatched.getPath();
final String dateTime = date;
// don't start picture preview immediately, but a little
// delayed...
continueWithPreview.postDelayed(new Runnable() {
#Override
public void run() {
try {
// EXIF Matadata change
ExifHelper exifHelper = new ExifHelper();
exifHelper.createInFile(fileName);
//EXIF Metadata read
exifHelper.readExifData();
exifHelper.createOutFile(fileNamePatched);
//Exif Metadata write
exifHelper.writeExifData(dateTime);
} catch (IOException e) {
e.printStackTrace();
Log.e("PictureActivity", e.getLocalizedMessage());
}
if (null != camera)
{
camera.startPreview();
Toast.makeText(AndroidCamera.this, "started!",
Toast.LENGTH_SHORT).show();
}
}
}, 2500);
I want to change the sqlite database .db file to excel.
But I am not able to find what exactly I have to do. Can anybody please elaborate in a simple way what I have to perform to achieve this task.
By searching on Google, so many links appears, but I am not able to understand the step by step way to do this.
I have followed these links:
1. How to convert excel sheet into database of sqlite in android
2. SQlite database programmatically convert into Excel file format in Android
3. http://opencsv.sourceforge.net/
My solution is to convert the sqlite database into csv in first step then in second step is to convert the csv file to xls and it works fine for me, you will need 2 libraries (opencsv-1.7.jar; poi-3.8-20120326.jar)
public class ExportDatabaseCSVTask extends AsyncTask<String, Void, Boolean>
{
private final ProgressDialog dialog = new ProgressDialog(DatabaseExampleActivity.this);
#Override
protected void onPreExecute()
{
this.dialog.setMessage("Exporting database...");
this.dialog.show();
}
protected Boolean doInBackground(final String... args)
{
File dbFile=getDatabasePath("database_name");
//AABDatabaseManager dbhelper = new AABDatabaseManager(getApplicationContext());
AABDatabaseManager dbhelper = new AABDatabaseManager(DatabaseExampleActivity.this) ;
System.out.println(dbFile); // displays the data base path in your logcat
File exportDir = new File(Environment.getExternalStorageDirectory(), "");
if (!exportDir.exists())
{
exportDir.mkdirs();
}
File file = new File(exportDir, "excerDB.csv");
try
{
if (file.createNewFile()){
System.out.println("File is created!");
System.out.println("myfile.csv "+file.getAbsolutePath());
}else{
System.out.println("File already exists.");
}
CSVWriter csvWrite = new CSVWriter(new FileWriter(file));
//SQLiteDatabase db = dbhelper.getWritableDatabase();
Cursor curCSV=db.getdb().rawQuery("select * from " + db.TABLE_NAME,null);
csvWrite.writeNext(curCSV.getColumnNames());
while(curCSV.moveToNext())
{
String arrStr[] ={curCSV.getString(0),curCSV.getString(1),curCSV.getString(2)};
/*curCSV.getString(3),curCSV.getString(4)};*/
csvWrite.writeNext(arrStr);
}
csvWrite.close();
curCSV.close();
/*String data="";
data=readSavedData();
data= data.replace(",", ";");
writeData(data);*/
return true;
}
catch(SQLException sqlEx)
{
Log.e("MainActivity", sqlEx.getMessage(), sqlEx);
return false;
}
catch (IOException e)
{
Log.e("MainActivity", e.getMessage(), e);
return false;
}
}
protected void onPostExecute(final Boolean success)
{
if (this.dialog.isShowing())
{
this.dialog.dismiss();
}
if (success)
{
Toast.makeText(DatabaseExampleActivity.this, "Export succeed", Toast.LENGTH_SHORT).show();
}
else
{
Toast.makeText(DatabaseExampleActivity.this, "Export failed", Toast.LENGTH_SHORT).show();
}
}}
Export CSV to XLS part
public class CSVToExcelConverter extends AsyncTask<String, Void, Boolean> {
private final ProgressDialog dialog = new ProgressDialog(DatabaseExampleActivity.this);
#Override
protected void onPreExecute()
{this.dialog.setMessage("Exporting to excel...");
this.dialog.show();}
#Override
protected Boolean doInBackground(String... params) {
ArrayList arList=null;
ArrayList al=null;
//File dbFile= new File(getDatabasePath("database_name").toString());
File dbFile=getDatabasePath("database_name");
String yes= dbFile.getAbsolutePath();
String inFilePath = Environment.getExternalStorageDirectory().toString()+"/excerDB.csv";
outFilePath = Environment.getExternalStorageDirectory().toString()+"/test.xls";
String thisLine;
int count=0;
try {
FileInputStream fis = new FileInputStream(inFilePath);
DataInputStream myInput = new DataInputStream(fis);
int i=0;
arList = new ArrayList();
while ((thisLine = myInput.readLine()) != null)
{
al = new ArrayList();
String strar[] = thisLine.split(",");
for(int j=0;j<strar.length;j++)
{
al.add(strar[j]);
}
arList.add(al);
System.out.println();
i++;
}} catch (Exception e) {
System.out.println("shit");
}
try
{
HSSFWorkbook hwb = new HSSFWorkbook();
HSSFSheet sheet = hwb.createSheet("new sheet");
for(int k=0;k<arList.size();k++)
{
ArrayList ardata = (ArrayList)arList.get(k);
HSSFRow row = sheet.createRow((short) 0+k);
for(int p=0;p<ardata.size();p++)
{
HSSFCell cell = row.createCell((short) p);
String data = ardata.get(p).toString();
if(data.startsWith("=")){
cell.setCellType(Cell.CELL_TYPE_STRING);
data=data.replaceAll("\"", "");
data=data.replaceAll("=", "");
cell.setCellValue(data);
}else if(data.startsWith("\"")){
data=data.replaceAll("\"", "");
cell.setCellType(Cell.CELL_TYPE_STRING);
cell.setCellValue(data);
}else{
data=data.replaceAll("\"", "");
cell.setCellType(Cell.CELL_TYPE_NUMERIC);
cell.setCellValue(data);
}
//*/
// cell.setCellValue(ardata.get(p).toString());
}
System.out.println();
}
FileOutputStream fileOut = new FileOutputStream(outFilePath);
hwb.write(fileOut);
fileOut.close();
System.out.println("Your excel file has been generated");
} catch ( Exception ex ) {
ex.printStackTrace();
} //main method ends
return true;
}
protected void onPostExecute(final Boolean success)
{
if (this.dialog.isShowing())
{
this.dialog.dismiss();
}
if (success)
{
Toast.makeText(DatabaseExampleActivity.this, "file is built!", Toast.LENGTH_LONG).show();
}
else
{
Toast.makeText(DatabaseExampleActivity.this, "file fail to build", Toast.LENGTH_SHORT).show();
}
}
}
I know this question is a little old but it provided me with the answer to the same question. I've cleaned up the code a little and done away with the need to write a csv file altogether by getting my database helper class to return me an ArrayList. Still using Apache POI though.
File folder =new File(Environment.getExternalStorageDirectory()+APP_FILES_PATH);
if(!folder.exists())
{
folder.mkdir();
}
DatabaseHelper dbHelper = DatabaseHelper.getInstance(context);
ArrayList<String[]> exts = dbHelper.getExtinguisherArray(1);
HSSFWorkbook hwb = new HSSFWorkbook();
HSSFSheet sheet = hwb.createSheet("extinguishers");
for(int x = 0; x < exts.size(); x++)
{
String[] arr = exts.get(x);
HSSFRow row = sheet.createRow(x);
for(int i = 0; i< arr.length; i++)
{
HSSFCell cell = row.createCell(i);
String data = arr[i];
cell.setCellValue(data);
}
}
FileOutputStream fileOut = new FileOutputStream(Environment.getExternalStorageDirectory()+APP_FILES_PATH+"file.xls");
hwb.write(fileOut);
fileOut.close();
Export Android SqliteDb to CSV format
You need to do these step...
add this jar file opencsv-1.7.jar http://www.java2s.com/Code/Jar/o/Downloadopencsv17jar.htm
And then use this code
public class ExportDatabaseToCSV{
Context context;
public ExportDatabaseToCSV(Context context) {
this.context=context;
}
public void exportDataBaseIntoCSV(){
CredentialDb db = new CredentialDb(context);//here CredentialDb is my database. you can create your db object.
File exportDir = new File(Environment.getExternalStorageDirectory(), "");
if (!exportDir.exists())
{
exportDir.mkdirs();
}
File file = new File(exportDir, "csvfilename.csv");
try
{
file.createNewFile();
CSVWriter csvWrite = new CSVWriter(new FileWriter(file));
SQLiteDatabase sql_db = db.getReadableDatabase();//here create a method ,and return SQLiteDatabaseObject.getReadableDatabase();
Cursor curCSV = sql_db.rawQuery("SELECT * FROM "+CredentialDb.TABLE_NAME,null);
csvWrite.writeNext(curCSV.getColumnNames());
while(curCSV.moveToNext())
{
//Which column you want to export you can add over here...
String arrStr[] ={curCSV.getString(0),curCSV.getString(1), curCSV.getString(2)};
csvWrite.writeNext(arrStr);
}
csvWrite.close();
curCSV.close();
}
catch(Exception sqlEx)
{
Log.e("Error:", sqlEx.getMessage(), sqlEx);
}
}
}
In addition to #user2324120's answer, and as we're in Android, you can directly add the libs to gradle (and therefore you don't need to download the jars) :
compile 'com.opencsv:opencsv:3.7'
compile 'org.apache.poi:poi:3.14'
I also did it a different way, a way more customisable one (and without useless CSV transition). Here it is, with a few comments :
public static Pair<Boolean, String> exportToXLS(Context context, boolean byAuthor) {
try {
HSSFWorkbook workbook = new HSSFWorkbook();
HSSFSheet sheet = workbook.createSheet(context.getString(R.string.sheet_name)); // Good for localization
initSheetColumns(context, workbook, sheet, byAuthor);
addBooksToSheet(sheet, byAuthor);
setColumsWidth(sheet);
OutputStream outputStream = new FileOutputStream(new File(Methods.getDownloadsDirectory(), byAuthor ? context.getString(R.string.mylibrary_by_author_xls) : context.getString(R.string.mylibrary_xls)).getAbsolutePath());
workbook.write(outputStream);
outputStream.flush();
outputStream.close();
return new Pair<>(true, context.getString(R.string.database_saved));
} catch (Exception e) {
e.printStackTrace();
return new Pair<>(false, context.getString(R.string.an_error_has_occured_during_xls_file_creation));
}
}
private static void initSheetColumns(Context context, HSSFWorkbook workbook, HSSFSheet sheet, boolean byAuthor) {
HSSFRow row = sheet.createRow(0);
HSSFCell cell = row.createCell(0);
cell.setCellValue(byAuthor ? context.getString(R.string.db_author) : context.getString(R.string.db_title));
cell = row.createCell(1);
cell.setCellValue(byAuthor ? context.getString(R.string.db_title) : context.getString(R.string.db_author));
cell = row.createCell(2);
cell.setCellValue(context.getString(R.string.db_publisheddate));
/*
etc.
*/
boldHeaders(workbook, row);
}
private static void boldHeaders(HSSFWorkbook workbook, HSSFRow row) {
HSSFCellStyle style = workbook.createCellStyle();
/* Do your own style
...
*/
for (int i = 0; i < 8; i++) {
row.getCell(i).setCellStyle(style);
}
}
// Allow data personalisation and localisation if needed
private static void addBooksToSheet(HSSFSheet sheet, boolean byAuthor) {
int i = 1;
List<Book> books = Book.listAll(Book.class); // I use Sugar library here, if you're not just make a simple db query to get your objects
Collections.sort(books, byAuthor ? Book.bookAuthorComparator : Book.bookNameComparator);
for (Book book : books) {
HSSFRow row = sheet.createRow(i);
HSSFCell cell = row.createCell(0);
cell.setCellValue(byAuthor ? getBookValue(book, true) : book.getTitle());
cell = row.createCell(1);
cell.setCellValue(byAuthor ? book.getTitle() : getBookValue(book, false));
cell = row.createCell(2);
cell.setCellValue(book.getPublishedDate());
/*
etc.
*/
i++;
}
}
private static void setColumsWidth(HSSFSheet sheet) {
for (int i = 0; i < 8; i++) {
sheet.setColumnWidth(i, 255 * getMaxNumCharacters(sheet, i)); // Autosize not working on Android
}
}
// My method to get the max num char, if it can hekp
public static int getMaxNumCharacters(Sheet sheet, int column) {
int max = 0;
for (int rowIndex = 0; rowIndex <= sheet.getLastRowNum(); rowIndex++) {
Row row = sheet.getRow(rowIndex);
if (row == null) {
continue;
}
Cell cell = row.getCell(column);
if (cell != null) {
int nb = cell.getStringCellValue().length();
if (nb > max) {
max = nb;
}
}
}
max = (int) (max * 1.1);
if (max > 255) {
return 255; // max 255 char for width
}
return max;
}
Hope it helps!
I have to understand this code to create my own app(almost based on this function):
public static String[][] ReadFilePerLine(Context context, String nom) {
int i = 0;
try {
FileInputStream fIn = context.openFileInput(nom);
InputStreamReader ipsr = new InputStreamReader(fIn);
BufferedReader b = new BufferedReader(ipsr);
i = getLineNumber(context, nom);
String[][] s = new String[2][i/2];
i = 0;
String ligne;
int j = 0;
while ((ligne = b.readLine()) != null) {
if (i % 2 == 0)
s[0][j] = ligne;
else {
s[1][j] = ligne;
j++;
}
i++;
}
fIn.close();
ipsr.close();
return s;
}
catch (Exception e)
{}
I'm not understanding why the using of a 2D array? and with two rows ?(String[][] s = new String[2][i/2];)
here is the data that it will be stored in the file:
data = date + " : " + y + "L/100KM"+ " " + value1 + "L "+ value2 + "KM\n";
Necessary functions:
public void updatelv(Activity activity) {
SharedPreferences preferences = PreferenceManager.getDefaultSharedPreferences(context);
String fileName = getResources().getString(R.string.fileName);
fileDir = "" + preferences.getString("login", "") + "."+ preferences.getString("marque", "") + ".";
s = myIO.ReadFilePerLine(getApplicationContext(), fileDir+fileName);
ListView L = (ListView) findViewById(R.id.lv);
L.setAdapter(new ArrayAdapter<String>(this, R.layout.list_item, s[0]));
for (int i = 0; i< s[0].length; i++) {
Log.d("Saves",s[0][i]);
}
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
setContentView(R.layout.histo);
context = getApplicationContext();
activity = this;
final SharedPreferences preferences = PreferenceManager
.getDefaultSharedPreferences(context);
String fileName = getResources().getString(R.string.fileName);
fileDir = "" + preferences.getString("login", "") + "."+ preferences.getString("marque", "") + ".";
s = myIO.ReadFilePerLine(getApplicationContext(), fileDir + fileName);
updatelv(this);
ListView L = (ListView) findViewById(R.id.lv);
L.setTextFilterEnabled(true);
L.setOnItemClickListener(new OnItemClickListener() {
#Override
public void onItemClick(AdapterView<?> parent, View view,
int position, long id) {
// When clicked, show a toast with the TextView text
String tmp = s[1][position];
if (tmp == null)
tmp = "Aucun fichier trouvé!";
Toast.makeText(getApplicationContext(), tmp, Toast.LENGTH_SHORT)
.show();
}
});
ReadFilePerLine function:
public static String[][] ReadFilePerLine(Context context, String nom) {
int i = 0;
try {
FileInputStream fIn = context.openFileInput(nom);
InputStreamReader ipsr = new InputStreamReader(fIn);
BufferedReader b = new BufferedReader(ipsr);
i = getLineNumber(context, nom);
String[][] s = new String[2][i/2];
i = 0;
String ligne;
int j = 0;
while ((ligne = b.readLine()) != null) {
if (i % 2 == 0)
s[0][j] = ligne;
else {
s[1][j] = ligne;
j++;
}
i++;
}
fIn.close();
ipsr.close();
return s;
}
catch (Exception e)
{
}
Thank you for you help.
The code is clearly reading from a file whose format consists of pairs of lines; it puts the first line of each pair in s[0][...] and the second line of each pair in s[1][...]. If your format doesn't have that peculiarity -- which it doesn't sound as if it does -- then you don't need to do that. Just make an ordinary 1-dimensional array of Strings.
It appears that what they are doing is breaking the file down into two lists (or String arrays, in this case), one which contains all the even-numbered lines, and one which contains all the odd-numbered lines. I'll comment up the code for you:
public static String[][] ReadFilePerLine(Context context, String nom) {
int i = 0;
try {
//open the specified input file and create a reader
FileInputStream fIn = context.openFileInput(nom);
InputStreamReader ipsr = new InputStreamReader(fIn);
BufferedReader b = new BufferedReader(ipsr);
//get the total number of lines in the file, and allocate
//a buffer large enough to hold them all
i = getLineNumber(context, nom);
String[][] s = new String[2][i/2];
i = 0; //set the current line to 0
String ligne;
int j = 0; //set the section index to 0
//now read through the lines in the file, and place every
//even-numbered line in the first section ('s[0]'), and every
//odd-numbered line in the second section ('s[1]')
while ((ligne = b.readLine()) != null) {
if (i % 2 == 0)
//even-numbered line, it goes into the first section
s[0][j] = ligne;
else {
//odd-numbered line, it goes into the second section
s[1][j] = ligne;
j++; //increment the section index
}
i++; //increment the line count
}
//done, cleanup and return
fIn.close();
ipsr.close();
return s;
}
catch (Exception e) {
//should at least log an error here...
}
}
As to why they chose to use a String[][], I cannot say. Probably for convenience, since they want a single object that they can return from this function that contains both lists. Personally I would use a Map that has two List instances in it, but the String[][] works just as well and is probably marginally more efficient.
Judging from your example data it does not appear that you need to use this format. But if you want to use it, you need to structure your data so that the key is on one line, and its associated value is on the next, like:
date
2011-03-19
userName
someGuy
it seems to read from a file, split it into the two dimensional array (based on row count).
Why it does it? I have no idea why you'd want that. Check out the function that it returns s to and find out!