I am trying to read a file of tokens, here is my code:
public class Prac1 {
public static void main(String[] args) {
try{ //File file = new File();
BufferedReader reader = null;
HashMap<String,String> symbolTable = new HashMap<String,String>();
//reader = new BufferedReader(new FileReader(file));
Scanner scan = new Scanner(
new BufferedReader(
new FileReader("/Users/Documents/Lab1/testCase1.txt")));
while(scan.hasNext()){
String i= scan.next();
System.out.println("test--->"+i);
}
}catch(Exception e){
}
}
}
*The file reads tokens but at the beginning and at the end of output it gives garbage value.*I want to eliminate these values.
Change your text preferences to plain text.
In Mac go to text -> preferences -> plain text option
Then create a new text file and it should work!
Related
I am new to Android.I need help to solve the error below.
Got stuck here.
public class ForecastFragment extends Fragment {
private ArrayAdapter<String> mForecastAdapter;
public ForecastFragment() {
}
#Override
public void onCreate(Bundle savedInstanceState) {
super.onCreate(savedInstanceState);
// Add this line in order for this fragment to handle menu events.
setHasOptionsMenu(true);
}
#Override
public void onCreateOptionsMenu(Menu menu, MenuInflater inflater) {
inflater.inflate(R.menu.forecastfragment, menu);
}
#Override
public boolean onOptionsItemSelected(MenuItem item) {
// Handle action bar item clicks here. The action bar will
// automatically handle clicks on the Home/Up button, so long
// as you specify a parent activity in AndroidManifest.xml.
int id = item.getItemId();
if (id == R.id.action_refresh) {
FetchWeatherTask weatherTask = new FetchWeatherTask();
weatherTask.execute("94043");
return true;
}
return super.onOptionsItemSelected(item);
}
#Override
public View onCreateView(LayoutInflater inflater, ViewGroup container,
Bundle savedInstanceState) {
// Create some dummy data for the ListView. Here's a sample weekly forecast
String[] data = {
"Mon 6/23 - Sunny - 31/17",
"Tue 6/24 - Foggy - 21/8",
"Wed 6/25 - Cloudy - 22/17",
"Thurs 6/26 - Rainy - 18/11",
"Fri 6/27 - Foggy - 21/10",
"Sat 6/28 - TRAPPED IN WEATHERSTATION - 23/18",
"Sun 6/29 - Sunny - 20/7"
};
List<String> weekForecast = new ArrayList<String>(Arrays.asList(data));
// Now that we have some dummy forecast data, create an ArrayAdapter.
// The ArrayAdapter will take data from a source (like our dummy forecast) and
// use it to populate the ListView it's attached to.
mForecastAdapter =
new ArrayAdapter<String>(
getActivity(), // The current context (this activity)
R.layout.list_item_forecast, // The name of the layout ID.
R.id.list_item_forecast_textview, // The ID of the textview to populate.
weekForecast);
View rootView = inflater.inflate(R.layout.fragment_main, container, false);
// Get a reference to the ListView, and attach this adapter to it.
ListView listView = (ListView) rootView.findViewById(R.id.listview_forecast);
listView.setAdapter(mForecastAdapter);
return rootView;
}
public class FetchWeatherTask extends AsyncTask<String, Void, String[]> {
private final String LOG_TAG = FetchWeatherTask.class.getSimpleName();
/* The date/time conversion code is going to be moved outside the asynctask later,
* so for convenience we're breaking it out into its own method now.
*/
private String getReadableDateString(long time){
// Because the API returns a unix timestamp (measured in seconds),
// it must be converted to milliseconds in order to be converted to valid date.
SimpleDateFormat shortenedDateFormat = new SimpleDateFormat("EEE MMM dd");
return shortenedDateFormat.format(time);
}
/**
* Prepare the weather high/lows for presentation.
*/
private String formatHighLows(double high, double low) {
// For presentation, assume the user doesn't care about tenths of a degree.
long roundedHigh = Math.round(high);
long roundedLow = Math.round(low);
String highLowStr = roundedHigh + "/" + roundedLow;
return highLowStr;
}
/**
* Take the String representing the complete forecast in JSON Format and
* pull out the data we need to construct the Strings needed for the wireframes.
*
* Fortunately parsing is easy: constructor takes the JSON string and converts it
* into an Object hierarchy for us.
*/
private String[] getWeatherDataFromJson(String forecastJsonStr, int numDays)
throws JSONException {
// These are the names of the JSON objects that need to be extracted.
final String OWM_LIST = "list";
final String OWM_WEATHER = "weather";
final String OWM_TEMPERATURE = "temp";
final String OWM_MAX = "max";
final String OWM_MIN = "min";
final String OWM_DESCRIPTION = "main";
JSONObject forecastJson = new JSONObject(forecastJsonStr);
JSONArray weatherArray = forecastJson.getJSONArray(OWM_LIST);
// OWM returns daily forecasts based upon the local time of the city that is being
// asked for, which means that we need to know the GMT offset to translate this data
// properly.
// Since this data is also sent in-order and the first day is always the
// current day, we're going to take advantage of that to get a nice
// normalized UTC date for all of our weather.
Time dayTime = new Time();
dayTime.setToNow();
// we start at the day returned by local time. Otherwise this is a mess.
int julianStartDay = Time.getJulianDay(System.currentTimeMillis(), dayTime.gmtoff);
// now we work exclusively in UTC
dayTime = new Time();
String[] resultStrs = new String[numDays];
for(int i = 0; i < weatherArray.length(); i++) {
// For now, using the format "Day, description, hi/low"
String day;
String description;
String highAndLow;
// Get the JSON object representing the day
JSONObject dayForecast = weatherArray.getJSONObject(i);
// The date/time is returned as a long. We need to convert that
// into something human-readable, since most people won't read "1400356800" as
// "this saturday".
long dateTime;
// Cheating to convert this to UTC time, which is what we want anyhow
dateTime = dayTime.setJulianDay(julianStartDay+i);
day = getReadableDateString(dateTime);
// description is in a child array called "weather", which is 1 element long.
JSONObject weatherObject = dayForecast.getJSONArray(OWM_WEATHER).getJSONObject(0);
description = weatherObject.getString(OWM_DESCRIPTION);
// Temperatures are in a child object called "temp". Try not to name variables
// "temp" when working with temperature. It confuses everybody.
JSONObject temperatureObject = dayForecast.getJSONObject(OWM_TEMPERATURE);
double high = temperatureObject.getDouble(OWM_MAX);
double low = temperatureObject.getDouble(OWM_MIN);
highAndLow = formatHighLows(high, low);
resultStrs[i] = day + " - " + description + " - " + highAndLow;
}
for (String s : resultStrs) {
Log.v(LOG_TAG, "Forecast entry: " + s);
}
return resultStrs;
}
#Override
protected String[] doInBackground(String... params) {
// If there's no zip code, there's nothing to look up. Verify size of params.
if (params.length == 0) {
return null;
}
// These two need to be declared outside the try/catch
// so that they can be closed in the finally block.
HttpURLConnection urlConnection = null;
BufferedReader reader = null;
// Will contain the raw JSON response as a string.
String forecastJsonStr = null;
String format = "json";
String units = "metric";
int numDays = 7;
try {
// Construct the URL for the OpenWeatherMap query
// Possible parameters are avaiable at OWM's forecast API page, at
// http://openweathermap.org/API#forecast
final String FORECAST_BASE_URL =
"http://api.openweathermap.org/data/2.5/forecast/daily?";
final String QUERY_PARAM = "q";
final String FORMAT_PARAM = "mode";
final String UNITS_PARAM = "units";
final String DAYS_PARAM = "cnt";
final String APPID_PARAM = "02867cfd75153da1eda43a17f213ffc5";
Uri builtUri = Uri.parse(FORECAST_BASE_URL).buildUpon()
.appendQueryParameter(QUERY_PARAM, params[0])
.appendQueryParameter(FORMAT_PARAM, format)
.appendQueryParameter(UNITS_PARAM, units)
.appendQueryParameter(DAYS_PARAM, Integer.toString(numDays))
.appendQueryParameter(APPID_PARAM, BuildConfig.OPEN_WEATHER_MAP_API_KEY)
.build();
URL url = new URL(builtUri.toString());
Log.v(LOG_TAG, "Built URI " + builtUri.toString());
// Create the request to OpenWeatherMap, and open the connection
urlConnection = (HttpURLConnection) url.openConnection();
urlConnection.setRequestMethod("GET");
urlConnection.connect();
// Read the input stream into a String
InputStream inputStream = urlConnection.getInputStream();
StringBuffer buffer = new StringBuffer();
if (inputStream == null) {
// Nothing to do.
return null;
}
reader = new BufferedReader(new InputStreamReader(inputStream));
String line;
while ((line = reader.readLine()) != null) {
// Since it's JSON, adding a newline isn't necessary (it won't affect parsing)
// But it does make debugging a *lot* easier if you print out the completed
// buffer for debugging.
buffer.append(line + "\n");
}
if (buffer.length() == 0) {
// Stream was empty. No point in parsing.
return null;
}
forecastJsonStr = buffer.toString();
Log.v(LOG_TAG, "Forecast string: " + forecastJsonStr);
} catch (IOException e) {
Log.e(LOG_TAG, "Error ", e);
// If the code didn't successfully get the weather data, there's no point in attemping
// to parse it.
return null;
} finally {
if (urlConnection != null) {
urlConnection.disconnect();
}
if (reader != null) {
try {
reader.close();
} catch (final IOException e) {
Log.e(LOG_TAG, "Error closing stream", e);
}
}
}
try {
return getWeatherDataFromJson(forecastJsonStr, numDays);
} catch (JSONException e) {
Log.e(LOG_TAG, e.getMessage(), e);
e.printStackTrace();
}
// This will only happen if there was an error getting or parsing the forecast.
return null;
}
}
}
}
}
[{
public final class BuildConfig {
public static final boolean DEBUG = Boolean.parseBoolean("true");
public static final String APPLICATION_ID = "com.example.patels.sunshine";
public static final String BUILD_TYPE = "debug";
public static final String FLAVOR = "";
public static final int VERSION_CODE = 1;
public static final String VERSION_NAME = "1.0";
// Fields from build type: debug
public static final String OPEN_WEATHER_MAP_API_KEY = MyOpenWeatherMapApiKey;
}
I have written this code....I got stuck here..Unable to solve the error.
Help me out....Thank you
Under the app folder you can find build.gradle file, in this make this below changes.
Since you are using a String you have to use this syntax:
it.buildConfigField "String" , "OPEN_WEATHER_MAP_API_KEY" , "\"MyOpenWeatherMapApiKey\""
The last parameter has to be a String.
You should create an account here http://openweathermap.org/ and when you register with your email, you get an APIKey for your account. Use this api key and replace the MyOpenWeatherMapApiKey in the following line:
public static final String OPEN_WEATHER_MAP_API_KEY = MyOpenWeatherMapApiKey;
Another alternative would be to write the APIKey in grandle file as proposed already.
import java.io.*;
public class ReadFile {
public static void main(String[] args) throws IOException {
File in = new File("in.txt");
//File out = new File("out.txt");
FileOutputStream fos= new FileOutputStream("o.txt");
//PrintWriter fw= new PrintWriter(out);
if(!in.exists())
{
in.createNewFile();
//System.out.println("Hey");
}
FileReader is = new FileReader(in);
BufferedReader br= new BufferedReader(is);
while(true)
{
if(in.canRead())
{
try {
System.out.println(br.readLine());
fos.write((br.readLine()).getBytes());
} catch (Exception e) {
// TODO Auto-generated catch block
fos.close();
br.close();
System.out.println("Im breaking");
break;
}
}
else
{
fos.close();
System.out.println("closed");
break;
)
}
}
}
//end of file
I am trying to copy text from one file to another file in Java.I know we can copy byte by byte but i want to do it using strings! What's wrong?
Actual file :
Output file :
If you working with Java7 you can use Files.copy(source.toPath(), dest.toPath()); so you do not have to read the file. Or use FileUtils.copyFile(source, dest); from apache commons io.
System.out.println(br.readLine());
fos.write((br.readLine()).getBytes());
You
Read one line, print it to stdout
Read another line, write it to fos
Thus some lines may be missing from output file. Also, readLine() drops the line-termination characters. You need to add them back by yourself.
I'm creating a GUI, and I use a method "getStudentInfo()" of the Student object return data type to retrieve information from the JTextFields and storing them into the "student" object.
public Student getStudentInfo() {
Student student = new Student();
String name = jtfName.getText();
student.setName(name);
String idNumber = jtfIDNumber.getText();
student.setIdNumber(idNumber);
String address = jtfAddress.getText();
student.setAddress(address);
String phoneNumber = jtfPhoneNumber.getText();
student.setPhoneNumber(phoneNumber);
String major = jtfMajor.getText();
student.setMajor(major);
return student;
}
Then, in a different class, I create an "Add" button that, when clicked, is supposed to add the "student" object into an ArrayList, and then write the ArrayList into a binary file.
private class AddButtonListener implements ActionListener {
public void actionPerformed(ActionEvent e) {
File studentFile = new File(FILENAME);
ArrayList<Student> studentList = new ArrayList<Student>();
studentList.add(text.getStudentInfo());
try {
FileOutputStream fos = new FileOutputStream(studentFile);
ObjectOutputStream oos = new ObjectOutputStream(fos);
oos.writeObject(studentList);
}
catch (FileNotFoundException fnf) {
fnf.printStackTrace();
}
catch (IOException ioe) {
ioe.printStackTrace();
}
}
}
But when I run the program and I write a student's info and add it to the binary file, then I go to add another student, it overwrites the previous student's info completely. Any help would be greatly appreciated.
In the actionPerformed method of your class, AddButtonListener, you have the following line of code:
FileOutputStream fos = new FileOutputStream(studentFile);
This constructor will open the file so bytes are written to the beginning of your file. Since you reopen this file each time the button is clicked, you are replacing the file contents with new data. Instead, use the constructor with the boolean parameter for appending bytes rather than overwriting...
FileOutputStream fos = new FileOutputStream(studentFile, true);
You can check out this constructor's details in the java documentation...
FileOutputStream constructor documentation
I'm using Wicket (not sure if it matters) but I'm using Workbook to create an excel file for a user to download. But I'm not sure how exactly to do this. What I would like to happen is the user clicks the button, a log is created and a prompt is given to the user to open (and save to temp files) or to save to their computer. The file is then deleted from the server side, or maybe it is stored in the User's session and deleted at end of session.
Can someone point me in the right direction? If I can have the file not saved in the session at all, that'd be create and have it just have it sent to the client using FileOutputStream somehow..
here is my current code:
private void excelCreator()
{
Workbook workbook = new HSSFWorkbook();
Sheet sheet = workbook.createSheet(WorkbookUtil.createSafeSheetName("SSA User ID " + currentSSAIDSelection2.getSsaUserId()));
Iterator<AuditLogEntry> auditLogEntrys = logList.iterator();
int i = 0;
while (auditLogEntrys.hasNext())
{
final AuditLogEntry auditLogEntry = auditLogEntrys.next();
Row row = sheet.createRow(i);
row.createCell(0).setCellValue(auditLogEntry.getTimeStamp());
row.createCell(1).setCellValue(auditLogEntry.getSourceName());
row.createCell(2).setCellValue(auditLogEntry.getCategory());
row.createCell(3).setCellValue(auditLogEntry.getSsaAdmin());
row.createCell(4).setCellValue(auditLogEntry.getAction());
i++;
}
try
{
FileOutputStream output = new FileOutputStream("ssaUserIDAccess.xls");
workbook.write(output);
output.close();
}catch(Exception e)
{
e.printStackTrace();
}
}
You would have to create a DownloadLink with the temporary file as input. The temporary File must be deleted after download (file.delete())).
Alternatively you can try this:
IResourceStream stream = new ByteArrayResourceStream(data, "application/vnd.ms-excel");
RequestCycle.get().scheduleRequestHandlerAfterCurrent(new ResourceStreamRequestHandler(stream, filename).setContentDisposition(ContentDisposition.ATTACHMENT));
In this case data is the byte[] content of your workbook which can be for example retrieved with output.toByteArray().
In case anyone runs into this problem here is my solution. There wasn't a lot of straight forward answers on this but this is my solution:
My excelCreator method handles the creation of the excel Sheet, and returns it as a file.
private File excelCreator()
{
Workbook workbook = new HSSFWorkbook();
File excelfile = new File("userIDAccess.xls");
logList = getServer().findAuditLogs(getUserId(), null);
Sheet sheet = workbook.createSheet(WorkbookUtil.createSafeSheetName("User ID " + getUserId()));
Iterator<AuditLogEntry> auditLogEntrys = logList.iterator();
int i = 0;
while (auditLogEntrys.hasNext())
{
final AuditLogEntry auditLogEntry = auditLogEntrys.next();
Row row = sheet.createRow(i);
row.createCell(0).setCellValue(auditLogEntry.getTimeStamp());
row.createCell(1).setCellValue(auditLogEntry.getSourceName());
row.createCell(2).setCellValue(auditLogEntry.getCategory());
row.createCell(3).setCellValue(auditLogEntry.getSsaAdmin());
row.createCell(4).setCellValue(auditLogEntry.getAction());
i++;
}
try
{
FileOutputStream output = new FileOutputStream(excelfile);
workbook.write(output);
output.close();
}catch(Exception e)
{
e.printStackTrace();
}
return excelfile;
}
IModel excelFileModel = new AbstractReadOnlyModel()
{
public Object getObject()
{
return excelCreator();
}
};
I created an IModel to capture the file created inside my excelCreator() method and returned.
auditDownloadlink = new DownloadLink("auditDownloadlink", excelFileModel);
I pass the I.D. of the download link, and then pass the imodel.
finally,
I call,
auditDownloadlink.setDeleteAfterDownload(true);
auditDownloadlink.setCacheDuration(Duration.NONE);
This deletes the file after it is created. And the cache setting is a setting to make sure it is compatible with all browsers (That's how I interpreted it, but you may not need it).
The Imodel creates the File on the fly so it doesn't have to be stored anywhere, and then the file is deleted once it is downloaded.
Hope this helps someone!
You could create a Resource to do this, and make a ResourceLink.
public class ExcelProducerResource extends AbstractResource
{
public ExcelProducerResource()
{
}
#Override
protected ResourceResponse newResourceResponse( Attributes attributes )
{
final String fileName = getFileName();
ResourceResponse resourceResponse = new ResourceResponse();
resourceResponse.setContentType( "application/vnd.openxmlformats-officedocument.spreadsheetml.sheet" );
resourceResponse.setCacheDuration( Duration.NONE );
resourceResponse.setFileName( fileName );
resourceResponse.setWriteCallback( new WriteCallback()
{
#Override
public void writeData( Attributes attributes ) throws IOException
{
OutputStream outputStream = attributes.getResponse().getOutputStream();
writeToStream( outputStream );
outputStream.close();
}
} );
return resourceResponse;
}
void writeToStream(OutputStream outputStream) throws IOException
{
//.. do stuff here :)
}
String getFileName()
{
//.. do stuff here :)
}
}
I developed RssFeed Application using LWUIT j2me(java) for 2 xml files, now I want to show those 2 xml files on LWUIT Tabs.
That means, when my application runs, default tab will be displayed (on that tab my first Rss xml file Titles should be displayed), and when the user click on tab2 my second Rss xml titles should be displayed.
I am able to display the same titles of one rss files on both the tabs, how to control my flow to achieve my task?
Here my code:
public class XMLMidlet extends MIDlet implements ActionListener {
public XMLMidlet() {
Display.init(this);
news = new Vector();
m_backCommand = new Command("Back");
cmdExit = new Command("EXIT");
cmdDetails = new Command("Details");
}
public void startApp() {
//RssFeed URL's
String urls[] = {"http://topnews-23.rss",
"http://topstory-12.rss"};
for(int i=0;i<urls.length;i++){
ParseThread myThread = new ParseThread(this,urls[i]);
//this will start the second thread
myThread.getXMLFeed(urls[i]);
}
}
//method called by the parsing thread
public void addNews(News newsItem,String url) {
try{
news.addElement(newsItem);
form1 = new Form();
myNewsList = new List(newsVector);
newsList =new List(newsVector);
myNewsList.setRenderer(new NewsListCellRenderer());
newsList.setRenderer(new NewsListCellRenderer());
tabs=new Tabs(Component.TOP);
tabs.addTab("TopNews", myNewsList);
tabs.addTab("Topstory",newsList);
form1.addComponent(tabs);
form1.show();
}
catch(Exception e){
e.printStackTrace();
}
}
You should move below code
myNewsList = new List(newsVector);
newsList =new List(newsVector);
myNewsList.setRenderer(new NewsListCellRenderer());
newsList.setRenderer(new NewsListCellRenderer());
tabs=new Tabs(Component.TOP);
form1 = new Form();
tabs=new Tabs(Component.TOP);
tabs.addTab("TopNews", myNewsList);
tabs.addTab("Topstory",newsList);
from addNews method to constructor XMLMidlet. addNews method should use url parameter to differ for which list the newsItem is directed.
Update
Below is how I think you should implement addNews method:
public void addNews(News newsItem, String url) {
if (url.endsWith("topnews-20.rss")) {
myNewsList.addElement(newsItem);
} else if (url.endsWith("topstory-25.rss")) {
newsList.addElement(newsItem);
}
}
serRenderer does not need to be called from addNews and form1.show() should be moved to startApp.