We Keep Coding

Getting Blank Date as string from a custom date method

I am making a date filter for which I have created a custom method for date to be parse in specific date format.
I have date with to two formats dd MMM yyyy & yyyy-mm-dd which is passed in a single method to be parse and return in format of yyyy-mm-dd. As I have a complex structure at end both type of formatted string will go under the date parsing method.
ISSUE:: I am getting a blank string as return from this method when format is in yyyy-mm-dd. please provide me inputs of where i am wrong. Below is the code
//fetching date from methods
String current_date=CurrentFilterPeriod.dateParsing("2017-04-02");
String prev_date=CurrentFilterPeriod.dateParsing("01 Apr 2017");
//singleton file for date filter method
public class CurrentFilterPeriod {
private static Calendar cal = getInstance();
private static Date current_date = cal.getTime();
//defined formats for date
private static SimpleDateFormat formatter = new SimpleDateFormat("dd MMM yyyy");
private static SimpleDateFormat formatterString = new SimpleDateFormat("yyyy-MM-dd");
//method for parsing date
public static String dateParsing(String date){
Date newDate;
String returnDate = "";
if (date.equals(formatter.toPattern())){
returnDate=date;
}
Log.e("DB","date===>"+date);
try {
newDate = formatter.parse(date);
Log.e("DB","New Date===>"+newDate);
returnDate=formatterString.format(newDate);
Log.e("DB","returnDate===>"+returnDate);
} catch (ParseException e) {
e.printStackTrace();
}
return returnDate;
}
}
RESULT:: current_date="" prev_date="2017-04-01"
I am stuck here please help me or tell me other methods to get by desired output.Want result in format of yyyy-mm-dd

As you want result format like: yyyy-mm-dd. You need to check your Date String with formatterString formatter.
Change your code with:
SimpleDateFormat format = new SimpleDateFormat("yyyy-MM-dd");
boolean isValidDate(String input) {
try {
format.parse(input);
return true;
}
catch(ParseException e){
return false;
}
}
Now call the method using:
//method for parsing date
public static String dateParsing(String date) {
Date newDate;
String returnDate = "";
if (isValidDate(date)) {
returnDate = date;
return returnDate;
} else {
Log.e("DB", "date===>" + date);
try {
newDate = formatter.parse(date);
Log.e("DB", "New Date===>" + newDate);
returnDate = formatterString.format(newDate);
Log.e("DB", "returnDate===>" + returnDate);
} catch (ParseException e) {
e.printStackTrace();
}
}
return returnDate;
}

Caldroid calendar unparsable date exception

I am trying to get the selected date in dd/MM/yyyy format from Caldroid calendar but when I am parsing the date it will throw an following error.
java.text.ParseException: Unparseable date: "Thu May 04 00:00:00 GMT 2017" (at offset 0)
Below is my code:-
final SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
final CaldroidListener caldroidListener = new CaldroidListener() {
#Override
public void onSelectDate(Date date, View view) {
try {
String dateParse = date.toString();
Log.d("Date before parse: ",date.toString());
sdf.parse(dateParse);
Log.d("Date after parse: ",dateParse);
eventDate.setText(dateParse);
}catch(ParseException e){
e.printStackTrace();
}
}
};

This does what you want your code to do (without the logging):
final SimpleDateFormat sdf = new SimpleDateFormat("dd/MM/yyyy");
final CaldroidListener caldroidListener = new CaldroidListener() {
#Override
public void onSelectDate(Date date, View view) {
eventDate.setText(sdf.format(date));
}
};
You use SimpleDateFormat#format to get a formatted string out of your Date.

Unparsable date exception: string to java.sql.date

I have a problem with parsing a string to sql.date
This code works in my project only the first time, it will parse the date normally, but second time it throws exception.
I printed the date the function receives and it is the same format, for example 02.02.2016 was okey, I only changed month to 02.04.2016 and the exception was raised.
private final SimpleDateFormat dateFormat = new SimpleDateFormat("dd.mm.yyyy");
private final String sqldateFormat = "yyyy-mm-dd";
public java.sql.Date changeDate(String date) {
String newDate = "";
try {
java.util.Date d = dateFormat.parse(date);
dateFormat.applyPattern(sqldateFormat);
newDate = dateFormat.format(d);
} catch (ParseException e) {
e.printStackTrace();
}
return java.sql.Date.valueOf(newDate);
}

Try this
private final SimpleDateFormat dateFormat = new SimpleDateFormat("dd.mm.yyyy");
private final SimpleDateFormat sqldateFormat = new SimpleDateFormat("yyyy-mm-dd");
public java.sql.Date changeDate(String date) {
String newDate = "";
try {
java.util.Date d = dateFormat.parse(date);
newDate = sqldateFormat.format(d);
} catch (ParseException e) {
e.printStackTrace();
}
return java.sql.Date.valueOf(newDate);
}
Because during the fisrt execution you are modifying the pattern of the SimpleDateFormat it won't be able to parse the second date.
dateFormat.applyPattern(sqldateFormat); will modify the pattern to "yyyy-mm-dd" and then parsing 02.04.2016 will throw an exception.

this is because you change pattern of dateFormat.
This will work:
private final SimpleDateFormat dateFormat = new SimpleDateFormat("dd.mm.yyyy");
private final SimpleDateFormat sqlFormat = new SimpleDateFormat("yyyy-mm-dd");
public java.sql.Date changeDate(String date) {
String newDate = "";
try {
java.util.Date d = dateFormat.parse(date);
newDate = sqlFormat.format(d);
} catch (Exception e) {
e.printStackTrace();
}
return java.sql.Date.valueOf(newDate);
}

Apparently, this will work for the first run, but not for the second. Your problem is that you call applyPattern(), so it'll expect the new dates in sql date format only.
Here is a little better code:
private final SimpleDateFormat dateFormat = new SimpleDateFormat("dd.mm.yyyy");
private final SimpleDateFormat sqlFormat = new SimpleDateFormat("yyyy-mm-dd");
public java.sql.Date changeDate(String date) {
String newDate = "";
try {
java.util.Date d = dateFormat.parse(date);
newDate = sqlFormat.format(d);
} catch (ParseException e) {
e.printStackTrace();
}
return java.sql.Date.valueOf(newDate);
}

Don't use valueOf().
If you have a java.util.Date and want a java.sql.Date (or java.sql.Timestamp), use the Date(long date) constructor:
java.sql.Date sqlDate = new java.sql.Date(utilDate.getTime());
Also, don't catch exceptions and continue execution without handling it (printing it is not handling it).
Meaning that your code should be:
private final SimpleDateFormat dateFormat = new SimpleDateFormat("dd.mm.yyyy");
public java.sql.Date changeDate(String date) {
try {
return new java.sql.Date(dateFormat.parse(date).getTime());
} catch (ParseException e) {
throw new IllegalArgumentException("Invalid date: " + date);
}
}
Warning: SimpleDateFormat is not thread-safe:
Date formats are not synchronized. It is recommended to create separate format instances for each thread. If multiple threads access a format concurrently, it must be synchronized externally.

Formatting and validating a date in JSF

So I want to format my dateinputfield as "dd-MM-yyyy" and then validate that the date is not before tomorrow.
This is the relevant code in my view:
<h:inputText id="dueDate" required="true" value="#{submitRepairBean.dueDate}">
<f:convertDateTime pattern="dd-MM-yyyy"/>
<f:validator validatorId="be.kdg.repaircafe.validators.DueDateValidator"/>
</h:inputText>
This is my custom validator:
#FacesValidator("be.kdg.repaircafe.validators.DueDateValidator")
public class DueDateValidator implements Validator {
#Override
public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException {
System.out.println(value.toString()); //For some reason this prints Wed Jul 23 02:00:00 CEST 2014 when inputting 23-07-2014
DateTime date = new DateTime(value.toString());
long dueDateMillis = date.getMillis();
long oneDayMillis = 86400000;
Calendar tomorrowMidnight = new GregorianCalendar();
// reset hour, minutes, seconds and millis
tomorrowMidnight.set(Calendar.HOUR_OF_DAY, 0);
tomorrowMidnight.set(Calendar.MINUTE, 0);
tomorrowMidnight.set(Calendar.SECOND, 0);
tomorrowMidnight.set(Calendar.MILLISECOND, 0);
tomorrowMidnight.add(Calendar.DAY_OF_MONTH, 1);
if (dueDateMillis + oneDayMillis < tomorrowMidnight.getTimeInMillis()) {
throw new ValidatorException(new FacesMessage("You can not have something repaired before tomorrow!"));
}
}
Now the thing I don't understand is why it doesn't print in the converted format (dd-MM-yyyy), even then I don't care so much as long as I get the correct amount of milliseconds.
However, the DateTime constructor then throws an exception that the date is in an invalid format.
I've tried using SimpleDateFormat as well, with no luck.

The converter it will show you the date in this format on the page (in the jsp/html page). What it does, is converting the date in a string in the format dd-mm-yyyy. When you pass the calue in the validate function, it is not converted in the string in the format dd-MM-yyyy. it is a date, dueDate is a date, so by printing value.toString() is just converts the date value to a string. So the object is a date and just by casting to Date is should work. if you want in the code to print it in the format dd-MM-yyyy try this
Date date = (Date) value;
SimpleDateFormat sdf = new SimpleDateFormat("dd-MM-yyyy");
String strDate = sdf.format(date);
System.out.println(strDate );

#FacesValidator("validator.dateValidator")
public class DateValidator implements Validator, ClientValidator {
final static String DATE_FORMAT = "dd-MM-yyyy";
public DateValidator() {
}
public void validate(FacesContext context, UIComponent component, Object value) throws ValidatorException {
if (value == null || StringUtils.isEmpty((String) value.toString())) {
return;
}
SimpleDateFormat objDf = new SimpleDateFormat(DATE_FORMAT);
objDf.setLenient(false);
try {
try {
Date data = new Date();
data.setDate(data.getDate() + 1);
if(objDf.parse(value.toString()).before(data)){
((UIInput) component).setValid(false);
throw new ValidatorException(new FacesMessage("You can not have something repaired before tomorrow!"));
}
} catch (ParseException e) {
((UIInput) component).setValid(false);
throw new ValidatorException(new FacesMessage(MessageUtils.ALERTA, "Data informada não Válida!", ""));
}
} catch (ParseException e) {
throw new ValidatorException(new FacesMessage("Invalid Date!"));
}
}
public Map<String, Object> getMetadata() {
return null;
}
public String getValidatorId() {
return "validator.dateValidator";
}
}

Previously working date-formatting code returns nothing on Micromax A111

I am using the following code to format date.
private String getDate(String datestring) {
Date date = null;
DateFormat writeFormat = new SimpleDateFormat("dd-MM-yyyy");
try {
date = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy",
Locale.ENGLISH).parse(datestring);
String formattedDate = "";
if (date != null) {
formattedDate = writeFormat.format(date);
}
Log.d("Complaint adapter", formattedDate);
return formattedDate;
} catch (ParseException e) {
e.printStackTrace();
}
return "";
}
This code works fine in some devices, but when run this same in Micromax A111, it returns nothing. That is not displayed in the given field. Can anyone help me to solve this problem.

Finally the following code worked for me.
private String getDate(String datestring) {
// TODO Auto-generated method stub
SimpleDateFormat currentformat = new SimpleDateFormat("EEE MMM dd HH:mm:ss zzz yyyy", java.util.Locale.getDefault());
SimpleDateFormat requiredformat = new SimpleDateFormat("dd-MM-yyyy", java.util.Locale.getDefault());
try {
Date date = null;
date = currentformat.parse(datestring);
datestring = requiredformat.format(date);
return datestring;
} catch (ParseException e) {
Log.e("Formating date", e.getMessage());
}
return datestring;
}