I used this coding to retrieve the Mysql data to the JTable.but it returns only the first data row of the relevant table of the database but then again it count the number of rows correctly and all it returns is same copy of the first row equal to the row count.
I'm new to Java and netbeans environment so if someone can help me to solve this problem i'll be really grateful and thank you in advance :)
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = DriverManager.getConnection("jdbc:mysql://localhost/data", "root", "1122");
Statement stat = (Statement) con.createStatement();
stat.executeQuery("select * from reserve;");
ResultSet rs=stat.getResultSet();
ResultSetMetaData md = rs.getMetaData();
int columnCount = md.getColumnCount();
Vector data=new Vector();
Vector columnNames= new Vector();
Vector row = new Vector(columnCount);
for(int i=1;i<=columnCount;i++){
columnNames.addElement(md.getColumnName(i));
}
while(rs.next()){
for(int i=1; i<=columnCount; i++){
row.addElement(rs.getObject(i));
}
data.addElement(row);
}
DefaultTableModel model = new DefaultTableModel(data, columnNames);
jTable1.setModel( model );
You keep adding to the same Vector row. Try creating a new instance for each iteration of rs.next().
You have an error with your Vector. Consider using something like :
Vector data = new Vector(columnCount);
Vector row = new Vector(columnCount);
Vector columnNames = new Vector(columnCount);
for (int i = 1; i <= columnCount; i++) {
columnNames.addElement(md.getColumnName(i));
}
while (rs.next()) {
for (int i = 1; i <= columnCount; i++) {
row.addElement(rs.getObject(i));
}
data.addElement(row);
row = new Vector(columnCount); // Create a new row Vector
}
DefaultTableModel model = new DefaultTableModel(data, columnNames);
jTable1.setModel( model );
Related
I seem to be have a problem when trying to get the coulmn count from a resultset's metadata. THe error is Exception in thread "AWT-EventQueue-0" java.lang.IllegalStateException: SQLite JDBC: inconsistent internal state.
THe idea is to use this table model to populate a JTable with the result from the database query. However when I do I get the above error.
The relevant code is:
public DefaultTableModel buildFlightModel()
throws SQLException {
query="SELECT Airline.AirlineName, Flight.FlightID, Flight.Location, Flight.Destination, Flight.ArriveTime, Flight.LeaveTime FROM Flight INNER JOIN Airline ON Airline.AirlineID=Flight.AirlineID;";
try {
Class.forName("org.sqlite.JDBC");
c = DriverManager.getConnection("jdbc:sqlite:coursework.db");
stmt = c.createStatement();
rs=stmt.executeQuery(query);
while(rs.next()){
//System.out.println(s);
}
} catch (Exception e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
ResultSetMetaData metaData = rs.getMetaData();
// names of columns
Vector<String> columnNames = new Vector<String>();
int columnCount = metaData.getColumnCount();
for (int column = 1; column <= columnCount; column++) {
columnNames.add(metaData.getColumnName(column));
}
// data of the table
Vector<Vector<Object>> data = new Vector<Vector<Object>>();
while (rs.next()) {
Vector<Object> vector = new Vector<Object>();
for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++) {
vector.add(rs.getObject(columnIndex));
}
data.add(vector);
}
return new DefaultTableModel(data, columnNames);
}
Any thoughts/ideas/help would be deeply appreciated. Thank you.
This exception is thrown when ResultSet.isclose() == true. Try to create a Clone of the MetaData before starting the Read-Loop.
I'm showing the method were the JTable is constructed, the error is when adding the rows inside the for (int i = 1; i <= numero_columnas; i++) loop, or the way the DefaultTableModel model = new DefaultTableModel(); is declared, I can't find the error.
public void verTablaTable (Connection db, String nombre) throws Exception{
Statement stmt=db.createStatement();
ResultSet sst_ResultSet = stmt.executeQuery("SELECT * FROM "+nombre);
ResultSetMetaData md = sst_ResultSet.getMetaData();
int numero_columnas = md.getColumnCount();
DefaultTableModel model = new DefaultTableModel();
for (int i=1;i<=numero_columnas; i++){
model.addColumn(md.getColumnName(i));
}
JTable tabla =new JTable(model);
DefaultTableModel model1 = (DefaultTableModel) tabla.getModel();
Vector row = new Vector();
row.setSize(numero_columnas);
while (sst_ResultSet.next()){
for (int i = 1; i <= numero_columnas; i++){
row.set(i-1,sst_ResultSet.getString(i));
}
model1.addRow(row);
}
tabla.setAutoResizeMode(JTable.AUTO_RESIZE_OFF);
JScrollPane sp_vertabla = new JScrollPane(tabla);
sp_vertabla.setHorizontalScrollBarPolicy(JScrollPane.HORIZONTAL_SCROLLBAR_AS_NEEDED);
sp_vertabla.setVerticalScrollBarPolicy(JScrollPane.VERTICAL_SCROLLBAR_AS_NEEDED);
sp_vertabla.setBounds(50,30,700,500);
JPanel cont_vertabla = new JPanel(null);
cont_vertabla.setPreferredSize(new Dimension(750,600));
cont_vertabla.add(sp_vertabla);
f_vertabla.setContentPane(cont_vertabla);
f_vertabla.pack();
f_vertabla.setDefaultCloseOperation(JFrame.DISPOSE_ON_CLOSE);
//f_vertabla.setResizable(false);
f_vertabla.setVisible(true);
f_vertabla.addWindowListener(this);
}
this is the way the JTable looks
The row listed in the above pic, is the last one in the mysql table
Try adding the line
Vector row = new Vector();
inside the while loop.
i already searched the whole web but I can't find a solution, so i decided to ask here.
Following problem: I am using those 2 methods to populate a JTable with a DefaultTableModel, the ResultSet shows the right amount of data entries (i already searched it with System.out.println) but the JTable always misses the first row
I am using a method to get a ResultSet like this:
public static JTable DBCFillBTableAuftraege() {
Connection con = null;
Statement stmt = null;
ResultSet rs = null;
JTable table = null;
try {
con = DriverManager.getConnection(host, uName, uPass);
stmt = con.createStatement( );
rs = stmt.executeQuery("SELECT a.auftrags_nr, k.firma, a.auftragsdatum, a.lieferdatum, a.rechnungsbetrag, k.name, k.strasse, k.plz, k.ort from auftrag a join kunde k on k.kunden_nr = a.kunden_nr ");
while (rs.next()) {
table = new JTable(tableModel(rs));
return table;
}
} catch (SQLException e) {
System.out.println(e);
} finally {
try {
if (rs != null) {
rs.close();
}
if (stmt != null) {
stmt.close();
}
con.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
return table;
}
Which then calls this method:
public static DefaultTableModel TableModel(ResultSet rs)
throws SQLException {
ResultSetMetaData metaData = rs.getMetaData();
System.out.println(rs);
// names of columns
Vector<String> columnNames = new Vector<String>();
int columnCount = metaData.getColumnCount();
for (int column = 1; column <= columnCount; column++) {
columnNames.add(metaData.getColumnName(column));
}
// data of the table
Vector<Vector<Object>> data = new Vector<Vector<Object>>();
while (rs.next()) {
Vector<Object> vector = new Vector<Object>();
for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++) {
vector.add(rs.getObject(columnIndex));
}
data.add(vector);
}
return new DefaultTableModel(data, columnNames);
}
In my main:
TableAuftrag = DBCFillBTableAuftraege();
scpaneBestell.setViewportView(TableAuftrag);
It works fine, it is showing me my column headers and the data, except one problem:
It is always missing the first row and starts with the second one
Your problem starts here...
// Move to first row...
while (rs.next()) {
table = new JTable(tableModel(rs));
return table;
}
and manifests
// Move to second row and beyond...
while (rs.next()) {
Vector<Object> vector = new Vector<Object>();
for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++) {
vector.add(rs.getObject(columnIndex));
}
data.add(vector);
}
Basically, in the first while (rs.next()), you move to the first row, but in the second while (rs.next()) you move to the second row, without handling the first...
It might be better to simply pass the ResultSet directly to the TableModel.
Convention would also suggest that you probably should not need to create a new JTable, but instead, just create a new TableModel and apply to a pre-existing table
while (rs.next()) {
table = new JTable(tableModel(rs));
return table;
}
You're consuming the first row of the result set here, and then call tableModel(), which consumes the other rows. The while loop is useless. Just do
table = new JTable(tableModel(rs));
return table;
I would like to create DefaultTableModel from ResultSet. To do that, I need Object[][].
For that, I have to specify the size of the object before I iterate through the table: I go to the rs.last(), then rs.getRow(), then rs.beforeFirst();
After that, the rs.next() does not executes in the while cycle.
What am I doing wrong?
public static DefaultTableModel buildTableModel(ResultSet _resultSet) {
ResultSetMetaData metaData;
Object[] columnNames = null;
Object[][] tableData = null;
int columnCount;
int currentRowNumber = 0;
try {
metaData = _resultSet.getMetaData();
columnCount = metaData.getColumnCount();
columnNames = new Object[columnCount];
_resultSet.last();
tableData = new Object[_resultSet.getRow()][columnCount];
_resultSet.beforeFirst();
for (int currentColumn = 0; currentColumn <= columnCount; currentColumn++) {
columnNames[currentColumn] = metaData.getColumnName(currentColumn + 1);
}
while (_resultSet.next()) {
for (int columnIndex = 0; columnIndex <= columnCount; columnIndex++) {
tableData[currentRowNumber][columnIndex] = _resultSet.getObject(columnIndex + 1);
}
currentRowNumber++;
}
} catch (SQLException ex) {
System.out.println("bad");
}
return new DefaultTableModel(tableData, columnNames);
}
Probably your ResultSet is not scroll insensitive, that is, it can only be traversed forward.
See the documentation here:
[...] A default ResultSet object is not updatable and has a cursor that moves forward only. Thus, you can iterate through it only once and only from the first row to the last row. [...]
To create a bi-directional one, do something like:
Connection conn = DriverManager.getConnection(...);
Statement stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ...);
ResultSet rset = stmt.executeQuery(sql);
At first you need to print column name from ResultSetMetaData. Than you apply _resultSet.last(); and _resultSet.beforeFirst();. This way it has been working my machine.
public static DefaultTableModel buildTableModel(ResultSet _resultSet) {
ResultSetMetaData metaData;
Object[] columnNames = null;
Object[][] tableData = null;
int columnCount;
int currentRowNumber = 0;
try {
metaData = _resultSet.getMetaData();
columnCount = metaData.getColumnCount();
columnNames = new Object[columnCount];
// Print column here.
for (int currentColumn = 0; currentColumn <= columnCount; currentColumn++) {
columnNames[currentColumn] = metaData.getColumnName(currentColumn + 1);
}
tableData = new Object[_resultSet.getRow()][columnCount];
//Here point resultSet cursor to last and beforeFirst.
_resultSet.last();
_resultSet.beforeFirst();
// After swaping the above part. Now it will enter on while loop.
while (_resultSet.next()) {
for (int columnIndex = 0; columnIndex <= columnCount; columnIndex++) {
tableData[currentRowNumber][columnIndex] = _resultSet.getObject(columnIndex + 1);
}
currentRowNumber++;
}
} catch (SQLException ex) {
System.out.println("bad");
}
return new DefaultTableModel(tableData, columnNames);
}
If is there any way to insert a resultset into jtable directly?
Bad idea.
You shouldn't be passing anything from the java.sql package out of your persistence tier.
You can certainly iterate over a ResultSet and load the contents into your DefaultTableModel. But I wouldn't recommend it.
Something like this:
public DefaultTableModel map(ResultSet resultSet) throws SQLException
{
DefaultTableModel defaultTableModel = new DefaultTableModel();
ResultSetMetaData meta = resultSet.getMetaData();
int numberOfColumns = meta.getColumnCount();
while (resultSet.next())
{
Object [] rowData = new Object[numberOfColumns];
for (int i = 0; i < rowData.length; ++i)
{
rowData[i] = resultSet.getObject(i+1);
}
defaultTableModel.addRow(rowData);
}
return defaultTableModel;
}