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Disable JTable cell in Java Netbeans

I need to disable edit on double click in each cell from Jtable in Java Netbeans. The JTable is connected to sqlite database and shows the database table record.
private void DisplayTable() {
try{
Class.forName("org.sqlite.JDBC");
Connection conn=DriverManager.getConnection("jdbc:sqlite:clientrec.sqlite");
String sql = "SELECT * FROM client";
pst = conn.prepareStatement(sql);
rs = pst.executeQuery();
t1.setModel(DbUtils.resultSetToTableModel (rs));
}
catch (Exception e){
JOptionPane.showMessageDialog(null, e);
} finally{
try{
rs.close();
pst.close();
}
catch(Exception e){
}
}
}
I also created onmouseclick event for the jtable to display selection in Jtextfields, combobox, jcalendar
private void t1MouseClicked(java.awt.event.MouseEvent evt) {
// TODO add your handling code here:
DefaultTableModel model=(DefaultTableModel) t1.getModel();
int number=t1.getSelectedRow();
String tc=t1.getModel().getValueAt(number, 0).toString();
try{
Class.forName("org.sqlite.JDBC");
Connection conn=DriverManager.getConnection("jdbc:sqlite:clientrec.sqlite");
String sql = "SELECT * FROM client WHERE ID="+tc+"";
pst = conn.prepareStatement(sql);
rs = pst.executeQuery();
if(rs.next()){
String id=rs.getString("ID");
String fullname=rs.getString("FullName");
String phone=rs.getString("Phone");
String allergy=rs.getString("Allergy");
String date=rs.getString("Date1");
String budgetpayed=rs.getString("BudgetPayed");
String totalbudget=rs.getString("TotalBudget");
String budgetleft=rs.getString("BudgetLeft");
String currency=rs.getString("Currency");
String datea=rs.getString("Dateappointment");
String description=rs.getString("Description");
FullName.setText(fullname);
Phone.setText(phone);
Allergy.setText(allergy);
((JTextField)Date1.getDateEditor().getUiComponent()).setText(date);
BudgetP.setText(budgetpayed);
TBudget.setText(totalbudget);
BudgetL.setText(budgetleft);
Curr.setSelectedItem(currency);
((JTextField)Date2.getDateEditor().getUiComponent()).setText(datea);
Desc.setText(description);
}
}catch (Exception ex){
JOptionPane.showMessageDialog(null, ex);
}
}

Override the isCellEditable(...) method of the JTable:
JTable table = new JTable(...)
{
#Override
public boolean isCellEditable(int row, int column)
{
return false;
}
};

Searching a record in SQL by an id in Java

In my SQL database single record consists of four rows: id, name, age and email. How to get a single record by typing in a JTextField id of that record? So later we can for example System.out.printIn(); it? I know that my question might be stupid for someone who is an SQL expert but I am only a beginner and after searching for this information in the tutorials I could not find it:(. Please help. Here is some of my source code:
public static Connection getConnection() throws Exception{
try{
String driver = "com.mysql.jdbc.Driver";
String url = "jdbc:mysql://some IP address/testdb";
String username = "some username";
String password = "some password";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url,username,password);
System.out.println("Connected");
return conn;
} catch(Exception e){System.out.println(e);}
return null;
}
public EsquelTest() {
IDname = new JTextField("");
submit = new JButton("go");
add(IDname);
add(submit);
submit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if(e.getSource() == submit) {
id = IDname.getText().toString();
try {
getConnection();
get(id);
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
}
});
setLayout(new GridLayout());
}
public static ArrayList<String> get(String idname) throws Exception{
try{
Connection con = getConnection();
PreparedStatement statement = con.prepareStatement("Statement needed to get the whole record by owning only an ID");
ResultSet result = statement.executeQuery();
ArrayList<String> array = new ArrayList<String>();
while(result.next()){
array.add(result.getString("last"));
}
System.out.println("All records have been selected!");
return array;
}catch(Exception e){System.out.println(e);}
return null;
}

If you are asking for only SQL statement it is: select * from yourtable where id = theIdThatIsfromTextFieldHere
Yet, if you simply google it you will find thousands of answers. here for instance.

The SQL Statement would be SELECT * FROM yourtable WHERE id = yourid. So to embed it into your code it would look something like this:
public static Connection getConnection() throws Exception{
try{
String driver = "com.mysql.jdbc.Driver";
String url = "jdbc:mysql://some IP address/testdb";
String username = "some username";
String password = "some password";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url,username,password);
System.out.println("Connected");
return conn;
} catch(Exception e){System.out.println(e);}
return null;
}
public EsquelTest() {
IDname = new JTextField("");
submit = new JButton("go");
add(IDname);
add(submit);
submit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if(e.getSource() == submit) {
id = IDname.getText().toString();
try {
getConnection();
get(id);
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
}
});
setLayout(new GridLayout());
}
public static ArrayList<String> get(String idname) throws Exception{
try{
Connection con = getConnection();
PreparedStatement statement = con.prepareStatement("SELECT * FROM {REPLACE WITH YOUR TABLE} WHERE id = "+idname);
ResultSet result = statement.executeQuery();
ArrayList<String> array = new ArrayList<String>();
while(result.next()){
array.add(result.getString("last"));
}
System.out.println("All records have been selected!");
return array;
}catch(Exception e){System.out.println(e);}
return null;
}
Just a Tip: Don't name you function "get" as this is a commonly used keyword in other programming languages that only causes confusion.

Try it:
public static Connection getConnection() throws Exception{
try{
String driver = "com.mysql.jdbc.Driver";
String url = "jdbc:mysql://some IP address/testdb";
String username = "some username";
String password = "some password";
Class.forName(driver);
Connection conn = DriverManager.getConnection(url,username,password);
System.out.println("Connected");
return conn;
} catch(Exception e){System.out.println(e);}
return null;
}
public EsquelTest() {
IDname = new JTextField("");
submit = new JButton("go");
add(IDname);
add(submit);
submit.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
if(e.getSource() == submit) {
id = IDname.getText().toString();
try {
getConnection();
for(String string:get(id)){
System.out.println(string);
}
// get(id);
} catch (Exception e1) {
// TODO Auto-generated catch block
e1.printStackTrace();
}
}
}
});
setLayout(new GridLayout());
}
public static ArrayList<String> get(String idname) throws Exception{
try{
Connection con = getConnection();
// You should replace "YourTableName" With table in databace that you work with it
PreparedStatement statement = con.prepareStatement("SELECT * FROM YourTableName WHERE id = '" + idName+"'");
//If type of your id in database is Int write this code :
// int id= Integer.parseInt(idName);
//PreparedStatement statement = con.prepareStatement("SELECT * FROM YourTableName WHERE id = " + idName);
ResultSet result = statement.executeQuery();
ArrayList<String> array = new ArrayList<String>();
result.next();
//This array has all data in single recorde
array.add(result.getString("id"));
array.add(result.getString("name"));
array.add(result.getString("age"));
array.add(result.getString("email"));
// I removed this rows becuse you have only one record
// while(result.next()){
//
// array.add(result.getString("last"));
// }
System.out.println("All records have been selected!");
return array;
}catch(Exception e){System.out.println(e);}
return null;
}

jFrame fields not saving to db

Am trying to save some field from my jFrame form but when i click the save button, i get the null pointer exception. Previously i was getting the errors that text field couldn't be null so i unchecked not null but it didn't work , i decided not to include Voucher_no in MySQL insert statement as it is an auto increment and its text field is not editable
Is there any problem with my code?
Am Using Mysql Workbench.
try {
Class.forName("com.mysql.jdbc.Driver").newInstance();
Connection con = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/canning?zeroDateTimeBehavior=convertToNull", "root", "");
con.setAutoCommit(false);
try {
// String kb = jTextField3.getText(); //voucher_no
String kc = (String) jComboBox3.getSelectedItem(); //factory
String kg = jTextField10.getText(); //fuel
Double ks = Double.valueOf(kg);
String ke = jTextField11.getText(); //electricity
Double kt = Double.valueOf(ke);
String kf = jTextField12.getText(); //manpower
Double ku = Double.valueOf(kf);
String kj = (String) jComboBox4.getSelectedItem(); //can_name
String kk = (String) jComboBox5.getSelectedItem(); //label name
String kq = jTextField23.getText();//no_of_cans
Double kv = Double.valueOf(kq);
String kr = jTextField24.getText();//no_of_labels
Double kw = Double.valueOf(kr);
String query1= "insert into production (date,factory,fuel,electricity,manpower,can_name,label_name,no_of_cans,no_of_labels)"
+ "values (?,?,?,?,?,?,?,?,?)";
try (PreparedStatement pst = con.prepareStatement(query1)){
// pst.setString(10, kb);
pst.setString(1, ((JTextField) jDate1.getDateEditor().getUiComponent()).getText());
pst.setString(2, kc);
pst.setDouble(3, ks);
pst.setDouble(4, kt);
pst.setDouble(5, ku);
pst.setString(6, kj);
pst.setString(7, kk);
pst.setDouble(8, kv);
pst.setDouble(9, kw);
pst.execute();
}
try {
int rows = jTable2.getRowCount();
for (int row = 0; row < rows; row++) {
String kd = (String) jTable2.getValueAt(row, 0);
Double kn = (Double) jTable2.getValueAt(row, 1);
try {
// Class.forName("com.mysql.jdbc.Driver").newInstance();
// Connection con = (Connection) DriverManager.getConnection("jdbc:mysql://localhost:3306/canning?zeroDateTimeBehavior=convertToNull", "root", "");
String query = "insert into production(product_name,product_quantity)"
+ "values (?,?)";
PreparedStatement update = con.prepareStatement(query);
update.setString(1, kd);
update.setDouble(2, kn);
update.addBatch();
update.executeBatch();
con.commit();
} catch (SQLException e) {
e.printStackTrace();
// JOptionPane.showMessageDialog(this, "Error in production Table");
}
}
} catch (Exception e) {
JOptionPane.showMessageDialog(this, "Invalid Entry in fields");
}
} catch (Exception e) {
e.printStackTrace();
// JOptionPane.showMessageDialog(null, "Invalid in fields");
}
} catch (Exception e) {
e.printStackTrace();
}

The code is doing
update.addBatch();
update.executeBatch();
con.commit();
executeBatch and commit must be done outside the loop.
The misunderstanding arises from "addBatch" that should have been named "addToBatch."

Try doing it this way. First create a connection class as follows;
import java.sql.Connection;
import java.sql.DriverManager;
public class db_connection
{
public Connection connection()
throws Exception
{
try
{
Connection conn = null;
String username = "root"; String password = "";
String driver = "com.mysql.jdbc.Driver";
String url = "jdbc:mysql://localhost:3306/database";
try {
Class.forName(driver);
} catch (Exception e) {
e.printStackTrace();
return null;
}
conn = DriverManager.getConnection(url, username, password);
conn.setAutoCommit(false);
return conn;
} catch (Exception e) {
e.printStackTrace();
System.exit(0);
}return null;
}
}
Then on your save button do something like this,
private void ButtonRegGroup_SubmitActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
if ((this.jTextFieldGrp_ReqAmnt.getText().equals(""))
|| (this.jTextFieldGrp_name.getText().equals(""))
|| (this.jTextFieldGrp_Id.getText().equals(""))
|| (this.jTextFieldGrp_prj_name.getText().equals(""))) {
JOptionPane.showMessageDialog(this, "Some fields are empty", this.title, this.error);
} else {
try {
this.con = ((Connection) new db_connection().connection());
this.pst = ((PreparedStatement) this.con.prepareStatement("insert into registered_projects(project_type,name,project_name,project_id,constituency,ward,requested_amount)values(?,?,?,?,?,?,?)"));
GroupRegDetails();
this.pst.setString(1, this.proj_type);
this.pst.setString(2, this.group_name);
this.pst.setString(3, this.proj_name);
this.pst.setInt(4, this.proj_id);
this.pst.setString(5, this.constituency);
this.pst.setString(6, this.ward);
this.pst.setInt(7, this.requested_amount);
int row = this.pst.executeUpdate();
con.commit();
if (row == 0) {
this.con.rollback();
JOptionPane.showInternalMessageDialog(this, "Didn't Register project", this.title, this.error);
}
JOptionPane.showMessageDialog(this, "Project Successfully Registered", this.title, this.infor);
} catch (Exception e) {
e.printStackTrace();
}
}
}
public void GroupRegDetails() {
this.group_name = this.jTextFieldGrp_name.getText();
this.proj_id = Integer.parseInt(this.jTextFieldGrp_Id.getText());
this.proj_name = this.jTextFieldGrp_prj_name.getText();
this.constituency = this.jComboBoxGrp_Comb_const.getSelectedItem().toString();
this.ward = this.jComboBoxGrp_comb_Ward.getSelectedItem().toString();
this.requested_amount = Integer.parseInt(this.jTextFieldGrp_ReqAmnt.getText());
this.proj_type = "Group";
}
And finally good practice is to put fields on a Jpanel and the Jpanel on a Jframe. Hope this helps.

How to auto refresh jComboBox data after update?

I have a jComboBox that getting data from MySQL server database.
When I add new data to database, the jComboBox doesn't show it, and I must reopen my program to add the new data to jComboBox.
How can I refresh jComboBox data automatically?
This is my code :
private void dataComboBox(){
try {
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/shop","root","");
Statement stat = con.createStatement();
String sql = "select id from perfume order by id asc";
ResultSet res = stat.executeQuery(sql);
while(res.next()){
Object[] ob = new Object[3];
ob[0] = res.getString(1);
jComboBox5.addItem(ob[0]);
}
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e);
}
}
private void showCBdata(){
try {
Connection con = DriverManager.getConnection("jdbc:mysql://localhost:3306/shop","root","");
Statement stat = con.createStatement();
String sql = "select name from perfume where id='"+jComboBox5.getSelectedItem()+"'";
ResultSet res = stat.executeQuery(sql);
while(res.next()){
Object[] ob = new Object[3];
ob[0]= res.getString(1);
jTextField8.setText((String) ob[0]);
}
} catch (Exception e) {
JOptionPane.showMessageDialog(null, e);
}
}
//call method
private void jComboBox5ActionPerformed(java.awt.event.ActionEvent evt) {
showCBdata();
}
can you help me?
thank you..

You can do it in this way it will automatically refresh the combobox
try {
comboBox.removeAllItems();
sql = "SELECT * FROM `table_name`";
rs = stmnt.executeQuery(sql);
while (rs.next()) {
String val = rs.getString("column_name");
comboBox.addItem(val);
}
} catch (SQLException ex) {
Logger.getLogger(DefineCustomer.class.getName()).log(Level.SEVERE, null, ex);
}
removeAllItems(); method will clean the combobox to insure that not to repeat values.
You do not need to create a separate Object to add in jComboBox instead you can add String too.

Inzimam Tariq IT's Code (above):
try {
comboBox.removeAllItems();
sql = "SELECT * FROM `table_name`";
rs = stmnt.executeQuery(sql);
while (rs.next()) {
String val = rs.getString("column_name");
comboBox.addItem(val);
}
} catch (SQLException ex) {
Logger.getLogger(DefineCustomer.class.getName()).log(Level.SEVERE, null, ex);
}
I suggest putting all of this code inside an ActionListener. So that each time there the mouse is entered over the comboBox the above code will run. You should do the following:
public void mouseEntered(MouseEvent e) {
//the above code goes here
}
I suggest using a mouseListener:
https://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html
But if you want to look at other ActionListeners you can see them here:
https://docs.oracle.com/javase/tutorial/uiswing/events/actionlistener.html

Once you add a new registry in the DB, do a removeAllItems comboBox.removeAllItems(); and repopulate de combobox,
My example:
jComboLicorerias.removeAllItems();
try {
Conector = Conecta.getConexion();
Statement St = Conector.createStatement();
try (ResultSet Rs = St.executeQuery(Query)) {
while (Rs.next()) {
jComboLicorerias.addItem(Rs.getString("nombreLicoreria"));
}
St.close();
}
} catch (SQLException sqle) {
JOptionPane.showMessageDialog(null, "Error en la consulta.");

radio button show values in combo box

I confused with this if-else because I'm new in Java & MySQL and I tried to make it by myself.
public Menu() {
initComponents();
try {
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://localhost:3306/restaurant", "root", "");
System.out.println("ODBC Connection Successful");
showCategory();
} catch (ClassNotFoundException | SQLException e) {
System.out.println("ODBC Connection Failed" + e);
}
}
if - else
private void showCategory() {
try {
Statement stmt;
stmt = con.createStatement();
if (rbMFood.isSelected()) {
ResultSet rs = stmt.executeQuery("SELECT * FROM menu_cat WHERE type_id = 'TY02'");
while (rs.next()) {
cmbMCat.addItem(rs.getString("menu_cat"));
}
} else {
ResultSet rs = stmt.executeQuery("SELECT * FROM menu_cat WHERE type_id = 'TY01'");
while (rs.next()) {
cmbMCat.addItem(rs.getString("menu_cat"));
}
}
} catch (Exception e) {
}
}
Radio Button
private void rbMFoodActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
type = "Food";
}
private void rbMDrinkActionPerformed(java.awt.event.ActionEvent evt) {
// TODO add your handling code here:
type = "Drink";
}
And I declare the function in the end of the program
private String type;
When I click drink / food, the category still drink's category.
The database
Any help would be greatly appreciated!

You are using rs.getString("menu_cat") But the format is rs.getString(<Column Name>) But you are using rs.getString(<Table Name>) As "menu_cat" is name of the table and not the name of the column.
AFTER POSTING CONSTRUCTOR
What I see from the code you have posted, is that You have called showCategory() in the constructor. This method is responsible for populating the JComboBox cmbMCat. Now the cmbMCat is being populated when you are creating the new Menu. After that the items list of the cmbMCat does not change.
So, What I suggest is that you call the showCategory() from the rbMFoodActionPerformed and rbMDrinkActionPerformed methods. I hope this will solve your problem.
Also add cmbMCat.removeAllItems() before Statement stmt; to remove all the items that are there in the cmbMCat and reset it with a fresh list of items.
After comment regarding the if-else
Change the showCatagory() as below:
private void showCategory() {
cmbMCat.removeAllItems();
try {
PreparedStatement stmt; //Used Prepared statement
String sql = "SELECT * FROM menu_cat WHERE type_id = ?";
stmt = con.prepareStatement(sql);
if (type.equals("Drink")) {
stmt.setString("TY01");
} else {
stmt.setString("TY02");
}
ResultSet rs = stmt.executeQuery();
while (rs.next()) {
cmbMCat.addItem(rs.getString("menu_cat"));
}
}
} catch (Exception e) {
}
}
Also note that you eventListener code should be:
private void rbMFoodActionPerformed(java.awt.event.ActionEvent evt){
type = "Food";
showCategory();
}
private void rbMDrinkActionPerformed(java.awt.event.ActionEvent evt){
type = "Drink";
showCategory();
}