Question

The weird behavior is that a java.sql.Timestamp that I create using the System.currentTimeMillis() method, is stored in my MySQL database as 1970-01-01 01:00:00.

The two timestamps I am creating are to mark the beginning and end of a monitoring task I am trying to perform, what follows are excepts from the code where the behavior occurs

final long startTime = System.currentTimeMillis();
while(numberOfTimeStepsPassed < numTimeStep) {
/*
* Code in here 
*/
}
final long endTime = System.currentTimeMillis();
return mysqlConnection.insertDataInformation(matrixOfRawData, name,Long.toString(startTime), 
                                                 Long.toString(endTime), Integer.toString(numTimeStep),
                                                 Integer.toString(matrixOfRawData[0].length), owner,
                                                 type);

And here is the code used for inserting the time stamps and other data into the MySQL database

public String insertDataInformation(final  double [][] matrix,
                                    final String ... params) {
    getConnection(lookUpName);
    String id = "";
    PreparedStatement dataInformationInsert = null;
    try {
        dataInformationInsert =
                databaseConnection.prepareStatement(DATA_INFORMATION_PREPARED_STATEMENT);
        id = DatabaseUtils.createUniqueId();
        int stepsMonitored = Integer.parseInt(params[STEPS_MONITORED]);
        int numberOfMarkets = Integer.parseInt(params[NUMBER_OF_MARKETS]);
        dataInformationInsert.setNString(ID_INDEX, id);
        dataInformationInsert.setNString(NAME_INDEX, params[0]);
        dataInformationInsert.setTimestamp(START_INDEX, new Timestamp(Long.parseLong(params[START_INDEX])));
        dataInformationInsert.setTimestamp(END_INDEX, new Timestamp(Long.parseLong(params[END_INDEX])));
        dataInformationInsert.setInt(STEPS_INDEX, stepsMonitored);
        dataInformationInsert.setInt(MARKETS_INDEX, numberOfMarkets);
        dataInformationInsert.setNString(OWNER_INDEX, params[OWNER]);
        dataInformationInsert.setNString(TYPE_INDEX, params[TYPE]);
        dataInformationInsert.executeUpdate();
        insertRawMatrix(matrix, id, Integer.toString(stepsMonitored), Integer.toString(numberOfMarkets));
    } catch (SQLException sqple) {
        // TODO Auto-generated catch block
        sqple.printStackTrace();
        System.out.println(sqple.getSQLState());
    } finally {
        close(dataInformationInsert);
        dataInformationInsert = null;
        close(databaseConnection);
    }
    return id;
}

The important lines of code are :

dataInformationInsert.setTimestamp(START_INDEX, new Timestamp(Long.parseLong(params[START_INDEX])));
dataInformationInsert.setTimestamp(END_INDEX, new Timestamp(Long.parseLong(params[END_INDEX])));

The JavaDocs on the TimeStamp ( http://docs.oracle.com/javase/1.5.0/docs/api/java/sql/Timestamp.html ) says that it takes in time in milliseconds since 1st January 1970 and a simple print test confirms this.

What I am looking for is:

• A reason for this behavior when trying to store timestamps in a MySQL database through java.sql.Timestamp?
• Any solutions to this behavior?
• Any possible alternatives?
• Any possible improvements?

EDIT:
Been asked to include what START_INDEX and END_INDEX are:

 private static final int END_INDEX = 4;
 private static final int START_INDEX = 3;

Apologises for not putting them in the original post.

Answer 1

Okay, look at your call:

insertDataInformation(matrixOfRawData, name, Long.toString(startTime), 
                      Long.toString(endTime), Integer.toString(numTimeStep),
                      Integer.toString(matrixOfRawData[0].length), owner,
                      type);

So params will have values:

0: name
1: start time
2: end time
3: numTimeStep
4: matrixOfRowData[0].length
5: owner
6: type

Then you’re doing:

dataInformationInsert.setTimestamp(START_INDEX,
    new Timestamp(Long.parseLong(params[START_INDEX])));

… where START_INDEX is 3.

So you’re using the value corresponding to numTimeStep as the value for the timestamp… I suspect you don’t want to do that.

I would strongly advise you to create a simple object type (possibly a nested type in the same class) to let you pass these parameters in a strongly typed, simple to get right fashion. The string conversion and the access by index are both unwarranted, and can easily give rise to errors.