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Parameter index out of range when filtering mysql data to show in a JTable

Good Day
I am trying to retrieve data from a database into jTable. When the user writes in the textfield the required data it displays it in the table.
What I get is
java.sql.SQLException: Parameter index out of range (1 > number of parameters, which is 0).
Here is my codes
try {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/hr","root","MZaa8891#");
String Sql="Select recName,phoneNo,quali,major,Uni,status,IntDate,interviewer from rect ";
ps= con.prepareStatement(Sql);
ps.setString(1, jTextField1.getText());
rs =ps.executeQuery();
DefaultTableModel model = (DefaultTableModel)jTable1.getModel();
model.setRowCount(0);
while(rs.next()){
Object obj [] = {
rs.getString("recName"),
rs.getString("phoneNo"),
rs.getString("quali"),
rs.getString("major"),
rs.getString("Uni"),
rs.getString("status"),
rs.getDate("IntDate"),
rs.getString("interviewer")
};
model.addRow(obj);
}
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e);
}
Any Ideas?

You have missed some parameter in the where clause:
Query: Select
recName,phoneNo,quali,major,Uni,status,IntDate,interviewer from rect
where something = ?
String Sql="Select recName,phoneNo,quali,major,Uni,status,IntDate,interviewer from rect where something = ?";
ps= con.prepareStatement(Sql);
ps.setString(1, jTextField1.getText());
rs =ps.executeQuery();

SQLException: invalid cursor state

Why am I getting a SQLException with my query?
PreparedStatement stmt = con.prepareStatement("SELECT note FROM NOTES4EME WHERE id=?");
stmt.setString(1,"1");
ResultSet a = stmt.executeQuery();
return a.getInt(1);
What am I missing?
I have a method :
public int afficheNote(int id) throws ClassNotFoundException, SQLException {
Class.forName("org.apache.derby.jdbc.ClientDriver");
String url = "jdbc:derby://localhost:1527/TLdb;create=true;user=root;password=root";
Connection con = DriverManager.getConnection(url);
String query = "SELECT NOTES FROM NOTES4EME WHERE ID = '" + id + "'";
//PreparedStatement stmt = con.prepareStatement(query);
PreparedStatement stmt = con.prepareStatement("SELECT note FROM NOTES4EME WHERE id=?");
stmt.setString(1,"1");
ResultSet a = stmt.executeQuery();
if (a.next()) {
return a.getInt(1);
}
return -1;
}
and I call this method in a .JSP :
<%
int a = mybean.afficheNote(1);
%>

Call next before invoking getInt
ResultSet a = stmt.executeQuery();
if (a.next()) {
return a.getInt(1);
} else {
throw new IllegalArgumentException("Nothing found for 1...");
}

The ResultSet Javadoc says (in part) initially the cursor is positioned before the first row. So you need to call next. Add something like
if (a.next()) {
return a.getInt(1);
}
return -1;

How to retrieve values from SQL when ID is in array form

The function below will pick the highest value and it will display value which are in column place1(in table placeseen) as output based on the ID.So far I only can get the highest value but not the value in place1.
I don't know what's wrong with my coding because the output is always shows empty.
private void pick_highest_value_here_and_display(ArrayList<Double> value) throws Exception {
// TODO Auto-generated method stub
double aa[]=value.stream().mapToDouble(v -> v.doubleValue()).toArray();
double highest=aa[0+1];
for(int i=0;i<aa.length;i++)
{
if(aa[i]>highest){
highest=aa[i];
String sql ="Select* from placeseen where ID =aa[i]";
DatabaseConnection db = new DatabaseConnection();
Connection conn =db.getConnection();
PreparedStatement ps = conn.prepareStatement(sql);
ResultSet rs = ps.executeQuery();
if (rs.next())
{
String aaa;
aaa=rs.getString("place1");
System.out.println(aaa);
}
ps.close();
rs.close();
conn.close();
}
}
System.out.println(highest);
}

instead of
String sql ="Select * from placeseen where ID =aa[i]";//aa[i] taking a value
use
String sql ="Select place1 from placeseen where ID =?";
PreparedStatement ps = conn.prepareStatement(sql);
ps.setDouble(1, aa[i]);
passing aa[i] variable value .
Avoid sql injection

You can try this
// as you are using preparedStatement you can use ? and then set value for it to prevent sql injection
String sql = "Select * from placeseen where ID = ?";
DatabaseConnection db = new DatabaseConnection();
Connection conn = db.getConnection();
PreparedStatement ps = conn.prepareStatement(sql);
ps.setDouble(1, aa[i]); // 1 represent first attribute represented by ?
System.out.println(ps); // this will print query in console
ResultSet rs = ps.executeQuery();
if (rs.next()) {
System.out.println("Inside rs.next()"); // for debug purpose
String aaa;
aaa=rs.getString("place1");
System.out.println(aaa);
}
// remaining code

How to insert a value form java to database mysql...?

I have searched to insert a value from application java into a mysql table.
Following there's my code. The result of it is a long row of error, but the first row is: java.sql.SQLException: Before start of result set
Connection con = null; //oggetto di connessione
try {
Class.forName("com.mysql.jdbc.Driver"); //connessione
con = DriverManager.getConnection("jdbc:mysql://localhost/autonoleggio", "root", "");//connessione vera e propria
//quarto va cambiato col nome del database creato
Statement st = con.createStatement();
ResultSet rs = st.executeQuery("SELECT * FROM dati"); // persone ->tabella presente nel database
if(targa.getText().equals(rs.getString("Targa")))
{
Statement insideStatement = con.createStatement();
ResultSet insideResultsSet = insideStatement.executeQuery(
"INSERT INTO dati (Cliente) VALUES ('"+inserisci.getText()+"');"
);
/*String query;
query="INSERT INTO dati (Cliente) VALUES ('"+inserisci.getText()+"');";
PreparedStatement statement = con.prepareStatement(query);
statement.executeUpdate();
statement.close(); */
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if(con != null) {
con.close();
}
}

The ResultSet object is sort of an iterator on the result returned from the database. Like any iterator, it starts before the first element, and needs to be advanced to point to it. In short, you're missing a call to ResultSet#next():
ResultSet rs = st.executeQuery("SELECT * FROM dati");
if (rs.next() && targa.getText().equals(rs.getString("Targa"))) {
// Here -^

Is there any way to print a preparedStatement to the console System.out.println

I need a way to view the preparedStatement for debugging here is my java code that I wish to print the preparedStatement to the console for.
public class UnitTestDMUtility_Select {
#Test
public void testQUERY_CHECKBOTHPARTS() throws Exception{
UnitTestHelper helper = new UnitTestHelper();
Connection con = helper.getConnection(helper.sourceDBUrl);
Connection conTarget = helper.getConnection(helper.targetDBUrl);
PreparedStatement stmt = con.prepareStatement(DMUtility.QUERY_CHECKBOTHPARTS);
stmt.setInt(1, 101);
ResultSet sourceVal = stmt.executeQuery();
//Here is the QUERY
//select count(*) from tr_demand where demandtypeid=101
stmt = conTarget.prepareStatement(DMUtility.QUERY_CHECKBOTHPARTS);
stmt.setInt(1, 101);
ResultSet targetVal = stmt.executeQuery();
assertTrue(helper.resultSetsEqual2(sourceVal,targetVal));
}
}

To answer your question, I output my queries to a log file ( and console ) by doing the following:
PreparedStatement stmt = con.prepareStatement(DMUtility.QUERY_CHECKBOTHPARTS);
stmt.setInt(1, 101);
//Write stmt to console:
System.out.println(stmt.toString());

For query debug I usually use the library jamon, it is a JDBC proxy that logs every statement is invoked