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Adding 30 days on the value from JDateChooser using Java netbeans

hi all I am working on a form using JDateChooser I want to get the value of date inputted by the user. Is there any ways that after storing the value of date in a variable can I add 30 days from the inputted date? This is my code in passing the date to a string variable:
String dates =((JTextField)date.getDateEditor().getUiComponent()).getText();
my problem is how can I pass the date into a variable where i can be able to add an additional 30 days on it?
please help me really need this for my project .

To manipulate a String with a date value, you first need to convert to a Date using SimpleDateFormat, then you can perform manipulation using a Calendar.
SimpleDateFormat datefmt = new SimpleDateFormat("MM/dd/yyyy"); // Or format you're using
Date date = datefmt.parse(dates);
Calendar cal = Calendar.getInstance();
cal.setTime(date);
cal.add(Calendar.DAY_OF_MONTH, 30); // Add 30 days
Date futureDate = cal.getTime();
If you need value for insertion into a database, you will of course use PreparedStatement, so you'll need a Timestamp instead:
// From Date
Timestamp futureTimestamp = new Timestamp(futureDate.getTime());
// Directly from Calendar
Timestamp futureTimestamp = new Timestamp(cal.getTimeInMillis());

How do I format a java.sql.date into this format: "MM-dd-yyyy"?

I need to get a java.sql.date in the following format "MM-dd-yyyy", but I need it to stay a java.sql.date so I can put it into a table as date field. So, it cannot be a String after the formatting, it has to end up as a java.sql.date object.
This is what I have tried so far:
java.util.Date
today=new Date();
String date = formatter.format(today);
Date todaydate = formatter.parse(date);
java.sql.Date fromdate = new java.sql.Date(todaydate.getTime());
java.sql.Date todate=new java.sql.Date(todaydate.getTime());
String tempfromdate=formatter.format(fromdate);
String temptodate=formatter.format(todate);
java.sql.Date fromdate1=(java.sql.Date) formatter.parse(tempfromdate);
java.sql.Date todate1=(java.sql.Date) formatter.parse(temptodate);

You can do it the same way as a java.util.Date (since java.sql.Date is a sub-class of java.util.Date) with a SimpleDateFormat
SimpleDateFormat sdf = new SimpleDateFormat(
"MM-dd-yyyy");
int year = 2014;
int month = 10;
int day = 31;
Calendar cal = Calendar.getInstance();
cal.set(Calendar.YEAR, year);
cal.set(Calendar.MONTH, month - 1); // <-- months start
// at 0.
cal.set(Calendar.DAY_OF_MONTH, day);
java.sql.Date date = new java.sql.Date(cal.getTimeInMillis());
System.out.println(sdf.format(date));
Output is the expected
10-31-2014

Use below code i have convert today date. learn from it and try with your code
Date today = new Date();
//If you print Date, you will get un formatted output
System.out.println("Today is : " + today);
//formatting date in Java using SimpleDateFormat
SimpleDateFormat DATE_FORMAT = new SimpleDateFormat("MM-dd-yyyy");
String date = DATE_FORMAT.format(today);
System.out.println("Today in MM-dd-yyyy format : " + date);
Date date1 = formatter.parse(date);
System.out.println(date1);
System.out.println(formatter.format(date1));

A simpler solution would be to just convert the date in the query to epoch before comparing.
SELECT date_column from YourTable where UNIX_TIMESTAMP(date_column) > ?;
Then, simply pass date.getTime() when binding value to ?.
NOTE: The UNIX_TIMESTAMP function is for MySQL. You'll find such functions for other databases too.

java.util.Date today=new Date();
java.sql.Date date=new java.sql.Date(today.getTime()); //your SQL date object
SimpleDateFormat simpDate = new SimpleDateFormat("MM-dd-yyyy");
System.out.println(simpDate.format(date)); //output String in MM-dd-yyyy
Note that it does not matter if your date is in format mm-dd-yyyy or any other format, when you compare date (java.sql.Date or java.util.Date) they will always be compared in form of the dates they represent. The format of date is just a way of setting or getting date in desired format.

The formatter.parse will only give you a java.util.Date not a java.sql.Date
once you have a java.util.Date you can convert it to a java.sql.Date by doing
java.sql.Date sqlDate = new java.sql.Date (normalDate.getTime ());
Also note that no dates have any built in format, it is in reality a class built on top of a number.

For anyone reading this in 2017 or later, the modern solution uses LocalDate from java.time, the modern Java date and time API, instead of java.sql.Date. The latter is long outdated.
Formatting your date
DateTimeFormatter formatter = DateTimeFormatter.ofPattern("MM-dd-uuuu", Locale.US);
LocalDate fromDate = LocalDate.now(ZoneId.of("Asia/Kolkata"));
String tempFromDate = fromDate.format(formatter);
System.out.println(tempFromDate);
This prints something like
11-25-2017
Don’t confuse your date value with its textual representation
Neither a LocalDate nor a java.sql.Date object has any inherent format. So please try — and try hard if necessary — to keep the two concepts apart, the date on one side and its presentation to a user on the other.
It’s like int and all other data types. An int can have a value of 4284. You may format this into 4,284 or 4 284, 004284 or even into hex representation. This does in no way alter the int itself. In the same way, formatting your date does not affect your date object. So use the string for presenting to the user, and use LocalDate for storing into your database (a modern JDBC driver or other modern means of database access wil be happy to do that, for example through PreparedStatement.setObject()).
Use explicit time zone
Getting today’s date is a time zone sensitive operation since it is not the same date in all time zones of the world. I strongly recommend you make this fact explicit in the code. In my snippet I have used Asia/Kolkata time zone, please substitute your desired time zone. You may use ZoneId.systemDefault() for your JVM’s time zone setting, but please be aware that this setting may be changed under our feet by other parts of your program or other programs running in the same JVM, so this is fragile.

How to retrieve chosen date from JDatechooser?

I am using Eclipse to do a college project on Java. I realized that java does not have a built in date selector like C#, so I downloaded and added JDateChooser. I tried to retrieve the chosen date but it failed:
String Date = dateChooser.getDate(); //I want to the date to be retrieved as string
Any ideas? Is there some kind of initialization that I must do?

Retrieve the date that the user selected by calling getDate(), which returns a Date object. Then convert that object into a String by calling SimpleDateFormat.format():
Date d;
SimpleDateFormat sdf;
String s;
d = dateChooser.getDate(); // Date selected by user
sdf = SimpleDateFormat("MM/dd/yyyy HH:mm:ss"); // Or whatever format you need
s = sdf.format(d); // Viola
See also: Question 5683728

If I have the right component, the Java Docs show that the getDate method returns Date
getDate
public java.util.Date getDate() Returns the date. If the
JDateChooser is started with a null date and no date was set by the
user, null is returned. Returns: the current date

String dob =new SimpleDateFormat("dd-MMM-yyyy").format(jDateChooser1.getDate());

Parsing date with different time zones

Even with about 15 years in Java one always stumbles over the topic of handling dates and times...
Here's the situation: I get a timestamp from some external system as a String representation. The timestamp's semantic is that it represents an UTC date. This timestamp has to be put in an entity and then into a PostgreSQL database in a TIMESTAMP field. Additionally I need to put the same timestamp as local time (in my case CEST) into the entity and then into the database in a TIMESTAMP WITH TIME ZONE field.
What is the right way to ensure that no matter what the settings of the machine executing the code are, the timestamps get stored correctly in the entity (to make some validations with other UTC timestamps) and in the database (to use them in reports later on)?
Here's the code, which worked fine on my local machine:
SimpleDateFormat sdfUTC = new SimpleDateFormat("yyyy-MM-dd'T'HH:mm:ss.SSS");
sdfUTC.setTimeZone(TimeZone.getTimeZone("UTC"));
Date utcTimestamp = sdfUTC.parse(utcTimestampString);
// getMachinesTimezone is some internal util method giving the TimeZone object of the machines Location
Calendar localTimestamp = new GregorianCalendar(getMachinesTimezone());
localTimestamp.setTimeInMillis(utcTimestamp.getTime());
But when executing the same code on the server, it resulted in different times, so I assume that it's not the correct way to handle it. Any suggestions?
PS: I read about Joda Time when searching in this forum, but in the given project I'm not able to introduce new libraries since I only change an existing module, so I have to live with the standard JDK1.6

If I understand correctly, You need to set the timezone on the same data/calendar object that you are printing. Like this:
private Locale locale = Locale.US;
private static final String[] tzStrings = {
"America/New_York",
"America/Chicago",
"America/Denver",
"America/Los_Angeles",
};
Date now = new Date();
for ( TimeZone z : zones) {
DateFormat df = new SimpleDateFormat("K:mm a,z", locale);
df.setTimeZone(z);
String result = df.format(now);
System.out.println(result);
}
if i set timezone to SimpleDateFormat it is working fine.
here is the sample code...
String date="05/19/2008 04:30 AM (EST)";
SimpleDateFormat sdf = new SimpleDateFormat("MM/dd/yyyy hh:mm aaa (z)");
TimeZone.setDefault(TimeZone.getTimeZone("PST"));
long millis = sdf.parse(date).getTime();
sdf.setTimeZone(TimeZone.getDefault());
System.out.println(sdf.format(new Date(millis)));

I think you have to set the target time zone in you Calendar object. I think something like:
Calendar localTimestamp = new GregorianCalendar(TimeZone.getTimeZone("GMT+10"));
localTimestamp.setTimeInMillis(utcTimestamp.getTime());
In other case Java takes the default system time zone for the Calendar instance.

You can do it by the below example code.
Date date = new Date();
DateFormat formatter = new SimpleDateFormat("dd MMM yyyy HH:mm:ss z");
formatter.setTimeZone(TimeZone.getTimeZone("CET"));
Date date1 = dateformat.parse(formatter.format(date));
// Set the formatter to use a different timezone
formatter.setTimeZone(TimeZone.getTimeZone("IST"));
Date date2 = dateformat.parse(formatter.format(date));
// Prints the date in the IST timezone
// System.out.println(formatter.format(date));

change string to date as per the required date Format

I have to get a Date in type Date, not in String.
I have this code:
DateFormat formatter = new SimpleDateFormat("MM/dd/yy");
Date date1 = new Date();
String date = (formatter.format(date1));
// At this point I get the date in correct format i.e 05/24/11
Date todaysDate = (Date)formatter.parse(date);
// But after this I get the date in format : Tue May 24 00:00:00 EDT 2011
// whereas I Want to get the date like above i.e 05/24/11
// And in type Date, not in type String
If anyone could help, thanks

The Date object just represents a point in time and has no notion of a format (or time zone). If you print out a Date object it first converts it to a String using the default formatting of EEE MMM dd HH:mm:ss zzz yyyy. If you want a specific formatting when you print it or otherwise represent it as a String, you'll need to use a formatter just like you already have.

In other words, you want Date.toString() to return the same as DateFormat.format()? You could just do exactly that:
public class MyDate extends Date {
DateFormat formatter = new SimpleDateFormat("MM/dd/yy");
public String toString() {
return this.formatter.format(this);
}
}
But do you really want to mix up presentation (date format) with your data?

There is no problem here, you have a Date representing and can save it into the DB as it is now. If you print it to the console it gets formatted according the default rules, this is why you think it is different from what you need, but it has actually already the right value.
So just go ahead and put it into your DB.
Chances are that you DB will hold on getting a Timestamp, in this case you can create one:
Date d = ...
java.sql.Timestamp ts = new java.sql.Timestamp(d.getTime());
and save this one.