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Java: Get time in "hh:MM:ss a" format [duplicate]

This question already has answers here:
How to format date and time in Android?
(26 answers)
Closed 3 years ago.
I was building an android app and i was using Date class in my project to get the current date. I formatted the date with simpledateformatter and displayed it like dd-mm-yyyy (i.e. day month year) .
Now i also want to get the time in format of hh:MM:ss a (hours minutes seconds AM/PM)
As i was using date's instance i saw that it displays date and time also ( in default format). So i tried to fetch time from the date's instance.(let's say d is date class instance). I also found getTime() method of date class and performed d.getTime() but it returned me a long (which is duration from some fixed time from past to current time). Now i want time in desired format but this getTime() method is giving me long.
May you provide me some way on how to process this long value to get the desired format of time out of it. For example , d.getTime() return me some value( say 11233) and i want in format like this (11:33:22).

You can make that
private final String DATE_FORMAT = "dd.MM.yyyy HH:mm:ss";
SimpleDateFormat sdf = new SimpleDateFormat(DATE_FORMAT);
Date got = sdf.parse(date);
It returns Date with time to you

Use this snippet to get the date and time both.
public String currentDateTime() {
Calendar c = Calendar.getInstance();
SimpleDateFormat dateformat = new SimpleDateFormat("dd-MMM-yyyy hh:mm:ss aa"); //it will give you the date in the formate that is given in the image
String datetime = dateformat.format(c.getTime()); // it will give you the date
return datetime;
}
Note: Take a look in the image .

Date().getTime() is providing you the timestamp
Change the format to your requirement like mm:hh:ss a
Kotlin
fun getDateTime():String {
val inputFormat = SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", Locale.getDefault())
val date = Date()
return inputFormat.format(date.time)
}
JAVA
private String getDateTime(){
SimpleDateFormat format=new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS'Z'", Locale.getDefault());
return format.format(new Date().getTime());
}

To check current date is less than expiration date [duplicate]

This question already has answers here:
How to compare LocalDate instances Java 8
(3 answers)
Number format exception while parsing the date to long
(3 answers)
Closed 4 years ago.
I'd like to check if the system date (e.g. the current date) is before an expiry date before opening my software.
I have written the following code, however it throws a NumberFormatException. Why might this be happening?
public class dateController implements Initializable {
#FXML Label lblDate;
Alert alert = new Alert(AlertType.INFORMATION);
#Override
public void initialize(URL location, ResourceBundle resources) {
DateFormat dateFormat = new SimpleDateFormat("dd/MM/yyyy");
Date date = new Date();
lblDate.setText(dateFormat.format(date));
String a ="19/09/2018";
String currentdate = lblDate.getText();
String LastRunDate = currentdate;
if(Integer.parseInt(currentdate) < Integer.parseInt(a)) {
alert.setHeaderText(null);
alert.setContentText("Successfull");
alert.show();
}
}
}

Why might this be happening?
Integer.parseInt is fine for parsing a string like 42 into an int. You are trying to parse a string like 17/09/2018 using that method. Your string does not represent a valid int value (and frankly I don’t know which integer you had expected to come out of it?) Therefore the parseInt method throws the NumberFormatException.
Then what to do instead?
Use LocalDate for representing a date and its isBefore (or isAfter) to compare with another date.
LocalDate expirationDate = LocalDate.of(2018, Month.SEPTEMBER, 19);
LocalDate today = LocalDate.now(ZoneId.systemDefault());
if (today.isBefore(expirationDate)) {
alert.setHeaderText(null);
alert.setContentText("Successful");
alert.show();
}
Notice how much simpler it is compared to your code in the question. In this case you need no formatting or parsing. I am using the JVM’s time zone setting to get today’s date (which you also did in the question). So a user may possibly push the expiration by a couple of hours by changing time zone. If you want to avoid it, you can also hardcode the time zone as for example ZoneId.of("Asia/Ust-Nera")
If you do need to parse a string like 19/09/2018:
DateTimeFormatter dateFormatter
= DateTimeFormatter.ofPattern("dd/MM/uuuu");
String a ="19/09/2018";
LocalDate expirationDate = LocalDate.parse(a, dateFormatter);
System.out.println("Expiration date is " + expirationDate);
This snippet outputs:
Expiration date is 2018-09-19
Stay away from Date, DateFormat and SimpleDateFormat. They are long outdated, and the last two in particular notoriously troublesome. Use java.time, the modern Java date and time API, instead.
Link: The Java™ Tutorials: Trail: Date Time

How to do subtraction from a particular date using Java [duplicate]

This question already has answers here:
Calendar date to yyyy-MM-dd format in java
(11 answers)
Closed 4 years ago.
I am encountering an issue which is related to Java Date Function.
I'm getting the date from Application (example: 6/5/18) which is in MM/DD/YY format. Now I need to do -2 from the date. I know how to do -2 from current system date using calendar object (see the below code).
Calendar cal = Calendar.getInstance();
cal.add(Calendar.DATE,-2);
DateFormat dateFormat = new SimpleDateFormat("MM/dd/yy");
String PastDate = dateFormat.format(cal.getTime());
info("Date is displayed as : "+ PastDate );
I'm not able to put the date which I'm getting from Application in this format. Can someone please help me? (Any other way to do it would also be fine)

I suggest you to use Java 8 compatible Date and Time types.
If you use java.time.LocalDate then this is the solution:
LocalDate.now().minusDays(2)

From your question, it seems that you have the challenge in dealing with formatting, and then doing the subtraction.
I would recommend Java Date and Time Apis for this purpose, using a formatter.
A junit method to achieve your requirement is given below
#Test
public void testDateFormatUsingJava8() {
CharSequence inputdateTxt = "6/5/18";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("M/d/yy");
LocalDate inputDate = LocalDate.parse(inputdateTxt, formatter);
System.out.println(inputDate.minusDays(2L).format(formatter));
}
#Test
public void testDateCalenderUsingStringSplit() {
String inputdateTxt = "6/5/18";
String[] dateComponenets = inputdateTxt.split("//");
Calendar cal = Calendar.getInstance();
//Know where are the year month and date are stored.
cal.set(Integer.parseInt(dateComponenets[2]), Integer.parseInt(dateComponenets[0]), Integer.parseInt(dateComponenets[2]) );
cal.add(Calendar.DATE,-2);
DateFormat dateFormat = new SimpleDateFormat("M/d/yy");
String pastDate = dateFormat.format(cal.getTime());
System.out.println("Date is displayed as : "+ pastDate );
}
#Test
public void testDateCalenderUsingJavaUtilDateApi() throws ParseException {
String inputdateTxt = "6/5/18";
DateFormat dateFormat = new SimpleDateFormat("M/d/yy");
Date date = dateFormat.parse(inputdateTxt);
Calendar cal = Calendar.getInstance();
cal.setTime(date);
cal.add(Calendar.DATE,-2);
String pastDate = dateFormat.format(cal.getTime());
System.out.println("Date is displayed as : "+ pastDate );
The reason why I use "M/d/yy" is because your question does not pad the date and month fields in the input date with a zero. If there is a guarantee that you receive a padded value in the date and month field, using "MM/dd/yy" is suggested.
See the following answer for your reference :
DateTimeFormatterSupport for Single Digit Values
EDIT: considering the limitation to not use Java 8 Date Time APIs, I have added two other alternatives to solve the problem. The OP is free to choose any one of the solutions. Kept the Java 8 solution intact for information purposes.

Calendar cal = Calendar.getInstance();
cal.set(2018, 5, 6); // add this, setting data from the value you parsed
cal.add(Calendar.DATE,-2);
DateFormat dateFormat = new SimpleDateFormat("MM/dd/yy");
String PastDate = dateFormat.format(cal.getTime());
System.out.println("Date is displayed as : "+ PastDate);

String to Date Conversion mm/dd/yy to YYYY-MM-DD in java [duplicate]

This question already has answers here:
Java Date Error
(8 answers)
Closed 4 years ago.
I want to convert String values in the format of mm/dd/yy to YYYY-MM-DD Date. how to do this conversion?
The input parameter is: 03/01/18
Code to convert String to Date is given below
public static Date stringToDateLinen(String dateVlaue) {
Date date = null;
SimpleDateFormat formatter = new SimpleDateFormat("yyyy-MM-dd");
try {
date = formatter.parse(dateVlaue);
} catch (ParseException e) {
e.printStackTrace();
}
return date;
}
When tried to convert using this method it shows the following error
java.text.ParseException: Unparseable date: "03/01/18"

As you say the input is in a different format, first convert the String to a valid Date object. Once you have the Date object you can format it into different types , as you want, check.
To Convert as Date,
SimpleDateFormat formatter = new SimpleDateFormat("MM/dd/yy");
date = formatter.parse(dateVlaue);
To Print it out in the other format,
SimpleDateFormat formatter1 = new SimpleDateFormat("yyyy-MM-dd");
dateString = formatter1.format(date)

You are writing it the wrong way. In fact, for the date you want to convert, you need to write
SimpleDateFormat formatter = new SimpleDateFormat("MM/dd/yy");

The format you are passing to SimpleDateFormat is ("yyyy-MM-dd") which expects date to be in form 2013-03-01 and hence the error.
You need to supply the correct format that you are passing your input as something like below
public static Date stringToDateLinen(String dateVlaue) {
Date date = null;
SimpleDateFormat formatter = new SimpleDateFormat("dd/MM/yy");
try {
date = formatter.parse(dateVlaue);
} catch (ParseException e) {
e.printStackTrace();
}
return date;
}

The solution for the above problem
Convert the String date value in the Format of "dd/mm/yy" to Date.
By using the converted Date can able to frame the required date format.
The method has given below
public static String stringToDateLinen(String dateVlaue) {
Date date = null;
SimpleDateFormat formatter = new SimpleDateFormat("dd/mm/yy");
String dateString = null;
try {
// convert to Date Format From "dd/mm/yy" to Date
date = formatter.parse(dateVlaue);
// from the Converted date to the required format eg : "yyyy-MM-dd"
SimpleDateFormat formatter1 = new SimpleDateFormat("yyyy-MM-dd");
dateString = formatter1.format(date);
} catch (ParseException e) {
e.printStackTrace();
}
return dateString;
}

EDIT: Your question said “String values in the format of mm/dd/yy”, but I understand from your comments that you meant “my input format is dd/mm/yy as string”, so I have changed the format pattern string in the below code accordingly. Otherwise the code is the same in both cases.
public static Optional<LocalDate> stringToDateLinen(String dateValue) {
DateTimeFormatter dateFormatter = DateTimeFormatter.ofPattern("dd/MM/yy");
try {
return Optional.of(LocalDate.parse(dateValue, dateFormatter));
} catch (DateTimeParseException dtpe) {
return Optional.empty();
}
}
Try it:
stringToDateLinen("03/01/18")
.ifPresentOrElse(System.out::println,
() -> System.out.println("Could not parse"));
Output:
2018-01-03
I recommend you stay away from SimpleDateFormat. It is long outdated and notoriously troublesome too. And Date is just as outdated. Instead use LocalDate and DateTimeFormatter from java.time, the modern Java date and time API. It is so much nicer to work with. A LocalDate is a date without time of day, so this suites your requirements much more nicely than a Date, which despite its name is a point in time. LocalDate.toString() produces exactly the format you said you desired (though the LocalDate doesn’t have a format in it).
My method interprets your 2-digit year as 2000-based, that is, from 2000 through 2099. Please think twice before deciding that this is what you want.
What would you want to happen if the string cannot be parsed into a valid date? I’m afraid that returning null is a NullPointerException waiting to happen and a subsequent debugging session to track down the root cause. You may consider letting the DateTimeParseException be thrown out of your method (just declare that in Javadoc) so the root cause is in the stack trace. Or even throw an AssertionError if the situation is not supposed to happen. In my code I am returning an Optional, which clearly signals to the caller that there may not be a result, which (I hope) prevents any NullPointerException. In the code calling the method I am using the ifPresentOrElse method introduced in Java 9. If not using Java 9 yet, use ifPresent and/or read more about using Optional elsewhere.
What went wrong in your code?
The other answers are correct: Your format pattern string used for parsing needs to match the input (not your output). The ParseException was thrown because the format pattern contained hyphens and the input slashes. It was good that you got the exception because another problem is that the order of year, month and day doesn’t match, neither does the number of digits in the year.
Link
Oracle tutorial: Date Time explaining how to use java.time.

java create date object using a value string

I am using this to get the current time :
java.util.Calendar cal = java.util.Calendar.getInstance();
System.out.println(new java.text.SimpleDateFormat("EEEE, dd/MM/yyyy/hh:mm:ss")
.format(cal.getTime()));
I want to put the value (which I print it) into a date object, I tried this:
Date currentDate = new Date(value);
but eclipse tells me that this function is not good.
Edit
the value is the value that I printed to you using system.out.println

Whenever you want to convert a String to Date object then use SimpleDateFormat#parse
Try to use
String dateInString = new java.text.SimpleDateFormat("EEEE, dd/MM/yyyy/hh:mm:ss")
.format(cal.getTime())
SimpleDateFormat formatter = new SimpleDateFormat("EEEE, dd/MM/yyyy/hh:mm:ss");
Date parsedDate = formatter.parse(dateInString);
.Additional thing is if you want to convert a Date to String then you should use SimpleDateFormat#format function.Now the Point for you is
new Date(String) is deprecated and not recommended now.Now whenever anyone wants to parse , then he/she should use SimpleDateFormat#parse.
refer the official doc for more Date and Time Patterns used in SimpleDateFormat options.

Use SimpleDateFormat parse method:
import java.text.DateFormat;
import java.text.SimpleDateFormat;
String inputString = "11-11-2012";
DateFormat dateFormat = new SimpleDateFormat("dd-MM-yyyy");
Date inputDate = dateFormat.parse(inputString, dateFormat );
Since we have Java 8 with LocalDate I would suggest use next:
import java.time.LocalDate;
import java.time.format.DateTimeFormatter;
String inputString = "11-11-2012";
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("dd-MM-yyyy");
LocalDate inputDate = LocalDate.parse(inputString,formatter);

import java.util.Date;
import java.text.SimpleDateFormat;
Above is the import method, below is the simple code for Date
SimpleDateFormat dateFormat = new SimpleDateFormat("yyyy/MM/dd HH:mm:ss");
Date date = new Date();
system.out.println((dateFormat.format(date)));

FIRST OF ALL KNOW THE REASON WHY ECLIPSE IS DOING SO.
Date has only one constructor Date(long date) which asks for date in long data type.
The constructor you are using
Date(String s)
Deprecated. As of JDK version 1.1, replaced by DateFormat.parse(String s).
Thats why eclipse tells that this function is not good.
See this official docs
http://docs.oracle.com/javase/6/docs/api/java/util/Date.html
Deprecated methods from your context -- Source -- http://www.coderanch.com/t/378728/java/java/Deprecated-methods
There are a number of reasons why a method or class may become deprecated. An API may not be easily extensible without breaking backwards compatibility, and thus be superseded by a more powerful API (e.g., java.util.Date has been deprecated in favor of Calendar, or the Java 1.0 event model). It may also simply not work or produce incorrect results under certain circumstances (e.g., some of the java.io stream classes do not work properly with some encodings). Sometimes an API is just ill-conceived (SingleThreadModel in the servlet API), and gets replaced by nothing. And some of the early calls have been replaced by "Java Bean"-compatible methods (size by getSize, bounds by getBounds etc.)
SEVRAL SOLUTIONS ARE THERE JUST GOOGLE IT--
You can use date(long date) By converting your date String into long milliseconds and stackoverflow has so many post for that purpose.
converting a date string into milliseconds in java

Try this :-
try{
String valuee="25/04/2013";
Date currentDate =new SimpleDateFormat("dd/MM/yyyy").parse(valuee);
System.out.println("Date is ::"+currentDate);
}catch(Exception e){
System.out.println("Error::"+e);
e.printStackTrace();
}
Output:-
Date is ::Thu Apr 25 00:00:00 GMT+05:30 2013
Your value should be proper format.
In your question also you have asked for this below :-
Date currentDate = new Date(value);
This style of date constructor is already deprecated.So, its no more use.Being we know that Date has 6 constructor.Read more

Here is the optimized solution to do it with SimpleDateFormat parse() method.
SimpleDateFormat formatter = new SimpleDateFormat(
"EEEE, dd/MM/yyyy/hh:mm:ss");
String strDate = formatter.format(new Date());
try {
Date pDate = formatter.parse(strDate);
} catch (ParseException e) { // note: parse method can throw ParseException
e.printStackTrace();
}
Few things to notice
We don't need to create a Calendar instance to get the current date
& time instead use new Date()
Also it doesn't require 2 instances of SimpleDateFormat as
found in the most voted answer for this question. It's just a
waste of memory
Furthermore, catching a generic exception like Exception is a bad practice when we know that the parse method only stands a chance to throw a ParseException. We need to be as specific as possible when dealing with Exceptions. You can refer, throws Exception bad practice?

try this, it worked for me.
String inputString = "01-01-1900";
Date inputDate= null;
try {
inputDate = new SimpleDateFormat("dd-MM-yyyy").parse(inputString);
} catch (ParseException e) {
e.printStackTrace();
}
dp.getDatePicker().setMinDate(inputDate.getTime());

It is because value coming String (Java Date object constructor for getting string is deprecated)
and Date(String) is deprecated.
Have a look at jodatime or you could put #SuppressWarnings({“deprecation”}) outside the method calling the Date(String) constructor.

What you're basically trying to do is this:-
Calendar cal = Calendar.getInstance();
Date date = cal.getTime();
The reason being, the String which you're printing is just a String representation of the Date in your required format. If you try to convert it to date, you'll eventually end up doing what I've mentioned above.
Formatting Date(cal.getTime()) to a String and trying to get back a Date from it - makes no sense. Date has no format as such. You can only get a String representation of that using the SDF.