John John - 26 days ago 21
Java Question

sqlite preparedstatement finalized

I have an error of

java.sql.SQLException: The prepared statement has been finalized

which happens when I call the same preparedStatement a second time. I am calling it in a method.

Here is the database Java class (the relevant piece)

//create the charge table. (ps is PreparedStatement)
try{
statement.executeUpdate("CREATE TABLE charge(username TEXT NOT NULL, date DATETIME DEFAULT CURRENT_TIMESTAMP, charge REAL, PRIMARY KEY(username, date));");
} catch (SQLException ex) {
System.out.println("charge table creation failed. exception" + ex);
}


Method that creates a charge:

public void createCharge(String username, double amount){
try {
System.out.println(username + amount);

ps = connection.prepareStatement("INSERT INTO charge VALUES(?, ?, ?);");
ps.setString(1, username);
ps.setDate(2, DateConvert.toSQLDate(Date.valueOf(LocalDate.MIN)));
ps.setDouble(3, amount);
ps.executeUpdate();
ps.clearParameters();

System.out.println("Complete");

} catch (SQLException ex) {
Logger.getLogger(MontsRentalDatabase.class.getName()).log(Level.SEVERE, null, ex);
}
}


This is in the class where the charge is created:

public void createCharge(String username, double amount){
try {
System.out.println(username + amount);

ps = connection.prepareStatement("INSERT INTO charge VALUES(?, ?, ?);");
ps.setString(1, username);
ps.setDate(2, DateConvert.toSQLDate(Date.valueOf(LocalDate.MIN)));
ps.setDouble(3, amount);
ps.executeUpdate(); //Line 170
ps.clearParameters();

System.out.println("Complete");

} catch (SQLException ex) {
Logger.getLogger(MontsRentalDatabase.class.getName()).log(Level.SEVERE, null, ex);
}
}


The class that converts a normal date to sqldate:
public class DateConvert {

public static java.sql.Date toSQLDate(java.util.Date date){
return new java.sql.Date(date.getTime());
}

public static java.util.Date toJavaDate(java.sql.Date date){
return new java.util.Date(date.getTime());
}
}


The error is in line 170 of create charge, which is when ps.executeUpdate runs. It runs successful the first time, fails on the second.
Log:

450100.0
Complete
450150.0
SEVERE: null
java.sql.SQLException: The prepared statement has been finalized
at org.sqlite.core.NativeDB.throwex(NativeDB.java:429)
at org.sqlite.core.NativeDB.reset(Native Method)
at org.sqlite.core.DB.executeUpdate(DB.java:878)
at org.sqlite.jdbc3.JDBC3PreparedStatement.executeUpdate(JDBC3PreparedStatement.java:99)
at server.RentalDatabase.createCharge(RentalDatabase.java:170)


Thanks for any help,
J

Answer

I believe that this is a bug in version 3.14.2.1 of the SQLite JDBC driver.

It seems to me that you're getting a unique constraint violation exception, but the SQLite JDBC driver is tripping over itself attempting to report this exception and some other exception is getting thrown instead.

I was able to reproduce your exception using sqlite-jdbc version 3.14.2.1 if I tried to insert the same data multiple times, e.g. by re-running your code. I downgraded the SQLite JDBC driver to 3.8.11.2 and I got the following exception after running your code:

java.sql.SQLException: [SQLITE_CONSTRAINT]  Abort due to constraint violation (UNIQUE constraint failed: charge.username, charge.date)
    at org.sqlite.core.DB.newSQLException(DB.java:890)
    at org.sqlite.core.DB.newSQLException(DB.java:901)
    at org.sqlite.core.DB.execute(DB.java:810)
    at org.sqlite.core.DB.executeUpdate(DB.java:847)
    at org.sqlite.jdbc3.JDBC3PreparedStatement.executeUpdate(JDBC3PreparedStatement.java:86)
    at com.example.MontsRentalDatabase.createCharge(MontsRentalDatabase.java:40)
    at com.example.Main.main(Main.java:17)

Of course, when re-running the program, the data I'm trying to insert is in the table already. So a unique constraint violation is to be expected.

I then added the line

        statement.execute("DROP TABLE IF EXISTS charge");

to createChargeTable(), above the line that creates the table. The code then ran successfully multiple times using either version of the SQLite JDBC driver.

This bug has now been fixed in sqlite-jdbc version 3.15.1, so the fix is therefore to upgrade to this version or later.