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I tried to get the value of html input type "date" using request.getParameter() in servlet class, converted it into java date in JDBC Class, then to sql date format.

but there is this exception java.text.ParseException: Unparseable date.

This is the HTML tag for date

input type="date" name="BirthDate"

This is the servlet code to get value from HTML page

String bDate = request.getParameter("BirthDate");

This is the JDBC Class code to convert it 

String bbd = user.getBDate();
DateFormat df = new SimpleDateFormat("dd/MM/yyy");
java.util.Date bbDate = df.parse(bbd);;
java.sql.Date bDate = new java.sql.Date(bbDate.getTime());
A. Maher
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    What was typed in the input field? If you are using at least Java 8 and at least JDBC 4.2, it’s better to parse into a `LocalDate` using a `DateTimeFormatter`. You can save the `LocalDate` directly to your SQL database, so saving a conversion. Also the two `Date` classes are long outdated and poorly designed, so you are going to have all the advantages. – Ole V.V. Sep 19 '18 at 17:03
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    A couple of points, A you have three not 4 y's in your simple date format. B I recommend using LocalDate over Date. Lastly if you are using this to write sql the sql.Date field will accept the toString of LocalDate in a query. – lvoelk Sep 19 '18 at 17:03
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    FYI, the terribly troublesome old date-time classes such as [`java.util.Date`](https://docs.oracle.com/javase/10/docs/api/java/util/Date.html), [`java.util.Calendar`](https://docs.oracle.com/javase/10/docs/api/java/util/Calendar.html), and `java.text.SimpleDateFormat` are now [legacy](https://en.wikipedia.org/wiki/Legacy_system), supplanted by the [*java.time*](https://docs.oracle.com/javase/10/docs/api/java/time/package-summary.html) classes built into Java 8 and later. See [*Tutorial* by Oracle](https://docs.oracle.com/javase/tutorial/datetime/TOC.html). – Basil Bourque Sep 19 '18 at 17:24

1 Answers1

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tl;dr

myPreparedStatement.setObject(                       // As of JDBC 4.2, pass java.time objects to your database.
    … ,
    LocalDate                                        // Represent a date-only value, without time-of-day and without time zone.
    .parse(                                          // Convert text to a `LocalDate` object.
        "23/01/2018" ,
        DateTimeFormatter.ofPattern( "dd/MM/uuuu" )  // Specify formatting pattern to match user input.
    )                                                // Returns a `LocalDate` object.
)

java.time

Use only java.time classes. Never use java.util.Date, java.sql.Date, Calendar, SimpleDateFormat, etc.

String input = "23/01/2018" ;
DateTimeFormatter f = DateTimeFormatter.ofPattern( "dd/MM/uuuu" ) ;
LocalDate ld = LocalDate.parse( input , f ) ;

As of JDBC 4.2, we can directly exchange java.time objects with the database.

myPreparedStatement.setObject( … , ld ) ;

Retrieval.

LocalDate ld = myResultSet.getObject( … , LocalDate.class ) ;

About java.time

The java.time framework is built into Java 8 and later. These classes supplant the troublesome old legacy date-time classes such as java.util.Date, Calendar, & SimpleDateFormat.

The Joda-Time project, now in maintenance mode, advises migration to the java.time classes.

To learn more, see the Oracle Tutorial. And search Stack Overflow for many examples and explanations. Specification is JSR 310.

You may exchange java.time objects directly with your database. Use a JDBC driver compliant with JDBC 4.2 or later. No need for strings, no need for java.sql.* classes.

Where to obtain the java.time classes?

The ThreeTen-Extra project extends java.time with additional classes. This project is a proving ground for possible future additions to java.time. You may find some useful classes here such as Interval, YearWeek, YearQuarter, and more.

Basil Bourque
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