Trying to load info from a database into an array and then into a combobox.
This is what I have so far - in interest of readability I took out the code that pertained to the other buttons and such on the form, whats left is just the jbombo code and the code that gets the info from the database.
Code:
import java.sql.*;
import java.sql.Connection;
import java.sql.DriverManager;
import java.util.ArrayList;
import javax.swing.DefaultComboBoxModel;
public class billingInfoUI extends javax.swing.JFrame {
public billingInfoUI() {
initComponents();
}
@SuppressWarnings("unchecked")
private void initComponents() {
jPanel1 = new javax.swing.JPanel();
hoursWorked = new javax.swing.JTextField();
jLabel1 = new javax.swing.JLabel();
flatRate = new javax.swing.JTextField();
jScrollPane1 = new javax.swing.JScrollPane();
workType = new javax.swing.JList();
jScrollPane2 = new javax.swing.JScrollPane();
jList2 = new javax.swing.JList();
jButton1 = new javax.swing.JButton();
jButton2 = new javax.swing.JButton();
jButton3 = new javax.swing.JButton();
jComboBox1 = new javax.swing.JComboBox();
setDefaultCloseOperation(javax.swing.WindowConstants.EXIT_ON_CLOSE);
jComboBox1.setModel(new DefaultComboBoxModel(customers));
public class CustomerData {
//database url "test" is the database name
private static final String JDBC_CONNECTION_URL = "jdbc:mysql://localhost/test";
//database username
private static final String DATABASE_USER = "root";
//database password
private static final String DATABASE_PASSWORD = "root";
// query to select customer data
private static final String SQL_FETCH_CUSTOMERS = "SELECT custName FROM customers";
private Connection connection = null;
public CustomerData(){
// setup database connection
initConnection();
}
/**
* create database connection
*/
private void initConnection() {
try {
//load the mysql driver
Class.forName("com.mysql.jdbc.Driver");
//create the database connection
connection = DriverManager.getConnection(JDBC_CONNECTION_URL, DATABASE_USER, DATABASE_PASSWORD);
} catch (ClassNotFoundException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
}
}
public void closeConnection(){
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
} finally {
connection = null;
}
}
}
public ArrayList fetchCustomerData(){
if (connection != null){
Statement statement = null;
try {
statement = connection.createStatement();
//get results from database
ResultSet resultSet = statement.executeQuery(SQL_FETCH_CUSTOMERS);
//get customers from resultset and return them to the app
return convertResultSetToCustomersArray(resultSet);
} catch (SQLException e) {
e.printStackTrace();
} finally {
//close the statement we just used
if (statement != null){
try {
statement.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}else{
System.out.println("NO VALID DATABASE CONNECTION, CAN'T FETCH CUSTOMER DATA!");
}
// if we reach this point, something went wrong, so return empty list
return new ArrayList();
}
public ArrayList convertResultSetToCustomersArray(ResultSet results) throws SQLException{
ArrayList customers = new ArrayList();
//loop the results and add customers to an ArrayList
while (results.next()){
customers.add(results.getString("custName"));
}
return customers;
}
public String[] customers = null;
public void initData(){
CustomerData customerData = new CustomerData();
ArrayList custArrayList = customerData.fetchCustomerData();
//get the array from the ArrayList and cast it to a String[]
customers = (String[]) custArrayList.toArray(new String[0]);
}
}
public static void main(String args[]) {
java.awt.EventQueue.invokeLater(new Runnable() {
public void run() {
new billingInfoUI().setVisible(true);
}
});
}
// Variables declaration - do not modify
private javax.swing.JTextField flatRate;
private javax.swing.JTextField hoursWorked;
private javax.swing.JButton jButton1;
private javax.swing.JButton jButton2;
private javax.swing.JButton jButton3;
private javax.swing.JComboBox jComboBox1;
private javax.swing.JLabel jLabel1;
private javax.swing.JList jList2;
private javax.swing.JPanel jPanel1;
private javax.swing.JScrollPane jScrollPane1;
private javax.swing.JScrollPane jScrollPane2;
private javax.swing.JList workType;
// End of variables declaration
}
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