Question

I need to convert a String like 2010-11-28 into Date type to be saved in a PostgreSQL database. I tried this code but when I check the result in a database both dates are null:

SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
Date validStartDate=null;
Date validEndDate=null;

    try {
        validStartDate = df.parse(startDate);
        validEndDate = df.parse(endDate);

    } catch (Exception e) {

      ...

    }

    Assigment a  = new Assignment(..., validStartDate, validEndDate);
    session.save(s);

——————————–Edit—————————-

startDate and endDate are Strings in a format yyyy-mm-dd like 2010-11-27. There is nothing in the stack trace (the conversion seems to somehow work). If there was something I would probably know what is wrong. After conversion the dates are stored in a postgres database. Yes, I used util.Date instead of sql.Date (probably that’s a first mistake).

——————————- Edit2—————————

The code is simplified but: the stack trace doesn’t show anything strange, validStartDate and validEndDate are converted to something like this Tue Nov 30 00:00:00 CET (so not null). The Assignment is indeed correctly saved in a database. The sql: insert into public.assignment (type, valid_start_date, valid_end_date, id) values (5, NULL, NULL, 2). I tried to use sql.Date but no success.

—————————-Assignment mapping—————–

<hibernate-mapping>
  <class name="model.Assignment" schema="public" table="assignment">
    <id name="id" type="int">
      <column name="id"/>
      <generator class="increment"/>
    </id>


    <property name="validStartDate" type="date">
            <column name="valid_start_date" length="13" />
        </property>
        <property name="validEndDate" type="date">
            <column name="valid_end_date" length="13" />
        </property>
        <property name="type" type="integer">
            <column name="type" />
        </property>

  </class>
</hibernate-mapping>

I’m using Hibernate to save user data. The String is created by a JQuery widget Datepicker. Does anyone know how to solve that problem? Thanks in advance for help.

Answer 1

A few comments with questions:

SimpleDateFormat df = new SimpleDateFormat("yyyy-MM-dd");
Date validStartDate=null;
Date validEndDate=null;

try {
    validStartDate = df.parse(startDate);
    validEndDate = df.parse(endDate);

} catch (Exception e) {
    // are there any exceptions thrown and caught here?
}

// are validStartDate and validEndDate non-null at this point? 
// is this code even executed? it won't be if an exception was thrown...
Assigment a  = new Assignment(..., validStartDate, validEndDate);

// where did this "s" come from? did you mean "session.save(a)"?
session.save(s);

Aside from these questions, you should check the following:

Is Hibernate really saving your Assignment in database?

Are your Hibernate mappings correct?

Did you try using java.sql.date?

What is the generated SQL? You can turn that option on by using <property name="show_sql">true</property> in your hibernate.cfg.xml file.

Only by checking all of above will you be able to solve your problem.