PreparedStatement does not work with mysql/JDBC

PreparedStatement does not work with mysql/JDBC

I tried to insert a userId (int) and a userName(String) using the
PreparedStatement using JDBC using the following method:
public boolean saveUser(int userId, String userName){
boolean saveStatus = false;
try {
connection.setAutoCommit(true);
String sql = "insert into testtable values(?,?)";
PreparedStatement statement = connection.prepareStatement(sql);
statement.setInt(1, userId);
statement.setString(2, userName);
saveStatus = statement.execute(sql);
} catch (SQLException e) {
e.printStackTrace();
}finally{
Connector.closeConnections();
}
return saveStatus;
}
I get the following stacktrace:
com.mysql.jdbc.exceptions.jdbc4.MySQLSyntaxErrorException: You have an
error in your SQL syntax; check the manual that corresponds to your MySQL
server version for the right syntax to use near '?,?)' at line 1
at sun.reflect.NativeConstructorAccessorImpl.newInstance0(Native Method)
at
sun.reflect.NativeConstructorAccessorImpl.newInstance(NativeConstructorAccessorImpl.java:57)
at
sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
at java.lang.reflect.Constructor.newInstance(Constructor.java:525)
at com.mysql.jdbc.Util.handleNewInstance(Util.java:411)
at com.mysql.jdbc.Util.getInstance(Util.java:386)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1054)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4187)
at com.mysql.jdbc.MysqlIO.checkErrorPacket(MysqlIO.java:4119)
at com.mysql.jdbc.MysqlIO.sendCommand(MysqlIO.java:2570)
at com.mysql.jdbc.MysqlIO.sqlQueryDirect(MysqlIO.java:2731)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2809)
at com.mysql.jdbc.ConnectionImpl.execSQL(ConnectionImpl.java:2758)
at com.mysql.jdbc.StatementImpl.execute(StatementImpl.java:894)
at com.mysql.jdbc.StatementImpl.execute(StatementImpl.java:732)
at org.aashis.jdbc.dao.TestTableDao.saveUser(TestTableDao.java:63)
at org.aashis.jdbc.TestDB.main(TestDB.java:10)
Save Status: false
What am I doing wrong?