I don't know why but the table doesnot display. Values are being added into base table in mysql but it doesnot display in jtable.
Connection con = null;
Statement stmt = null;
try{
Class.forName("com.mysql.jdbc.Driver");
con = DriverManager.getConnection(DB_URL, USER, PASS);
stmt = con.createStatement();
String sql = "insert into customers "+
"values("+id+", \""+name+"\", "+"\""+add+"\", "+pno+");";
stmt.executeUpdate(sql);
ResultSet rs = stmt.executeQuery("Select * from customers;");
DefaultTableModel model = new DefaultTableModel();
JTable table = new JTable(model);
JScrollPane scrollPane = new JScrollPane(table);
model.addColumn("CustID");
model.addColumn("CustName");
model.addColumn("CustAdd");
model.addColumn("PhoneNo");
while(rs.next()){
int tid = rs.getInt("custid");
String tname = rs.getString("custname");
String tadd = rs.getString("custadd");
long tpno = rs.getLong("phoneno");
model.addRow(new Object[]{tid, tname, tadd, tpno});
}
table.setVisible(true);
}catch(SQLException se){
jOptionPane1.showMessageDialog(this, se);
}catch(Exception e){
.
.
.
You add the JTable to the JScrollPane, but it does not look like you are adding the JScrollPane to anything. (Unless there is code that we are not seeing.)
Related
I am trying to make a java program can call a table by its name... but the problem is I couldnt figure out how to check if the table is exist or not in database... I am using phpmyadmin data base and here is my code if there is someone can help me ...
enter image description here
public boolean istableNameexist(String un){
boolean uexist = false;
Connection con = myConnection.getconnection();
PreparedStatement ps;
ResultSet rs;
try {
ps = con.prepareStatement("SELECT * FROM `javacontactapp` WHERE TABLE_NAME = ?");
ps.setString(1,name.getText());
rs = ps.executeQuery();
if (rs.next()){
uexist = true;
}
} catch (Exception e) {
System.out.println("wrong");
}
return uexist;
}
public void openfatura(ActionEvent actionEvent) {
String ff1 = name.getText();
Connection con = myConnection.getconnection();
if (!name.getText().isEmpty()) {
if (istableNameexist(name.getText())){
try {
PreparedStatement ps = con.prepareStatement("SELECT `dafat`, `sinif` ,`number` , `price`, `type`, `total` FROM " + ff1 + " WHERE `id` = 1");
ResultSet resultset = ps.executeQuery();
I'm trying to get two data(GenreID & GameID) from two different tables(genre & games) and insert them into another table(games_genre). However, it will close the connection to the database after inserting the GenreID successfully even though i had created another new connection to the database.
I have tried to create connection1 and connection2 to the same database. Connection1 is used to insert GenreID and connection2 is used to insert GameID
<%# page import="java.sql.*,java.util.*,java.text.*,java.text.SimpleDateFormat" %>
String gametitle = request.getParameter("gametitle");
String [] checkbox1 = request.getParameterValues("checkbox");
try {
Class.forName("com.mysql.cj.jdbc.Driver");
String connURL ="jdbc:mysql://localhost/assignment?user=root&password=root&serverTimezone=UTC";
Connection conn = DriverManager.getConnection(connURL);
Connection conn2 = DriverManager.getConnection(connURL);
Statement stmt = conn.createStatement();
if (checkbox1!= null){
for(String s: checkbox1){
String sqlStr2 = "Select * FROM genre WHERE GenreName='" + s + "'";
ResultSet rs = stmt.executeQuery(sqlStr2);
while(rs.next()){
String genreid = rs.getString("GenreID");
String sqlStr3 = "INSERT INTO games_genre(GenreID) VALUES ('" + genreid + "')";
int j = stmt.executeUpdate(sqlStr3);
if (j>0) {
out.println("Adding GenreID Successfully!");}
}
}
}
conn.close();
Statement stmt2 = conn2.createStatement();
String sqlStr4 = "Select * FROM games WHERE GameTitle='" + gametitle +"'";
ResultSet rs2 = stmt2.executeQuery(sqlStr4);
if(rs2.next()){
String gameid = rs2.getString("GameID");
String sqlStr5 = "INSERT INTO games_genre(GameID) VALUES ('" + gameid + "')";
int k = stmt2.executeUpdate(sqlStr5);
if (k>0) {
out.println("Adding GameID Successfully!");
}
}
conn2.close();
} catch (Exception e) {
out.println("Error :" + e);
}
Adding Game Successfully! Adding GenreID Successfully! Error :java.sql.SQLException: Operation not allowed after ResultSet closed
I don't understand that why do you need to create two Connection as you need to access same database . So ,just create multiple Statement to execute multiple query like below :
Statement stmt=null;
Statement stmt2=null;
try {
Class.forName("com.mysql.cj.jdbc.Driver");
String connURL ="jdbc:mysql://localhost/assignment?user=root&password=root&serverTimezone=UTC";
Connection conn = DriverManager.getConnection(connURL);
stmt = conn.createStatement();
if (checkbox1!= null){
....
}
<!--using same conn object -->
stmt2 = conn.createStatement();
String sqlStr4 = "Select * FROM games WHERE GameTitle='" + gametitle +"'";
ResultSet rs2 = stmt2.executeQuery(sqlStr4);
if(rs2.next()){
...
}
<!--finally close connection-->
conn.close();
} catch (Exception e) {
out.println("Error :" + e);
}
Note : Also try using PreparedStatement for preventing from Sql Injection as concatenating values into a query string is unsafe .
I am running a query on ID column but I don't want it to be visible in my frame/pane. How can I achieve this? Shall I make another table, is there a function in sql/mysql which allows to hide columns? I tried to google it but havent found anything yet.
Here is the code:
public void tableChanged(TableModelEvent e) {
int row = e.getFirstRow();
int col = e.getColumn();
model = (MyTableModel) e.getSource();
String stulpPav = model.getColumnName(col);
Object data = model.getValueAt(row, col);
Object studId = model.getValueAt(row, 0);
System.out.println("tableChanded works");
try {
new ImportData(stulpPav, data, studId);
} catch (ClassNotFoundException e1) {
e1.printStackTrace();
} catch (SQLException e1) {
e1.printStackTrace();
}
}
public class ImportData {
Connection connection = TableWithBottomLine.getConnection();
public ImportData(String a, Object b, Object c)
throws ClassNotFoundException, SQLException {
Statement stmt = null;
try {
String stulpPav = a;
String duom = b.toString();
String studId = c.toString();
System.out.println(duom);
connection.setAutoCommit(false);
stmt = connection.createStatement();
stmt.addBatch("update finance.fin set " + stulpPav + " = " + duom
+ " where ID = " + studId + ";");
stmt.executeBatch();
connection.commit();
} catch (BatchUpdateException e) {
e.printStackTrace();
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (stmt != null)
stmt.close();
connection.setAutoCommit(true);
System.out.println("Data was imported to database");
}
}
}
public class MyTableModel extends AbstractTableModel{
int rowCount;
Object data [][];
String columnNames [];
public MyTableModel() throws SQLException{
String query ="SELECT ID, tbl_Date as Date, Flat, Mobile, Food, Alcohol, Transport, Outdoor, Pauls_stuff, Income, Stuff FROM finance.fin";
ResultSet rs ;
Connection connection = TableWithBottomLine.getConnection();
Statement stmt = null;
stmt = connection.createStatement();
rs = stmt.executeQuery(query);
rs.last();
rowCount = rs.getRow();
data = new Object[rowCount][11];
rs = stmt.executeQuery(query);
for (int iEil = 0; iEil < rowCount; iEil++){
rs.next();
data[iEil][0] = rs.getInt("ID");
data[iEil][1] = rs.getDate("Date");
data[iEil][2] = rs.getFloat("Flat");
data[iEil][3] = rs.getFloat("Mobile");
data[iEil][4] = rs.getFloat("Food");
data[iEil][5] = rs.getFloat("Alcohol");
data[iEil][6] = rs.getFloat("Transport");
data[iEil][7] = rs.getFloat("Outdoor");
data[iEil][8] = rs.getFloat("Pauls_stuff");
data[iEil][9] = rs.getFloat("Income");
data[iEil][10] = rs.getFloat("Stuff");
}
String[] columnName = {"ID", "Date","Flat","Mobile"
,"Food","Alcohol","Transport", "Outdoor", "Pauls_stuff", "Income", "Stuff"};
columnNames = columnName;
}
This has solved my problem:
table.removeColumn(table.getColumnModel().getColumn(0));
I placed this in my class contructor. This lets remove the column from the view of the table but column 'ID' is still contained in the TableModel. I found that many people looking for an option to exclude specific column (like autoincrement) from SELECT statement in sql / mysql but the language itself doesn't have that feature. So I hope this solution will help others as well.
Don't put ID in the select part of the query
String query ="SELECT tbl_Date as Date, Flat, Mobile, Food, Alcohol, Transport,
Outdoor, Pauls_stuff, Income, Stuff FROM finance.fin";
I have a SQL Server 2008 database and I want to select data by using a String variable... here is the selection code in java:
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
Connection con = DriverManager.getConnection("jdbc:odbc:DDS_DSN");
Statement st = con.createStatement();
ResultSet rs;
rs = st.executeQuery("SELECT source_port FROM request_dns WHERE destination_port = 53");
while ( rs.next() ) {
String source_port = rs.getString("source_port");
System.out.println(source_port);
}
con.close();
} catch (Exception e) {
System.out.println(e);
}
I want to make it like this:
String x = "53";
try
{
.
.
rs = st.executeQuery("SELECT source_port FROM request_dns WHERE destination_port = x");
.
.
}
could you please tell me how to do that?...
Thank you
Kind Regards
You want a parameterized query, like this:
int x = 53;
PreparedStatement ps = con.prepareStatement(
"SELECT source_port FROM request_dns " +
"WHERE destination_port = ?");
ps.setInt(1, x);
ResultSet rs = ps.executeQuery();
I have
employee(id, name, company, salary);
Need to display data for given id
public static void Connect(String conString, String username, String password, int id) throws SQLException{
try {
Class.forName("com.mysql.jdbc.Driver");
Connection conn = null;
conn = DriverManager.getConnection(conString, username, password);
String query = "select * from employee where id = " + id + "" ;
ResultSet rs = null;
Statement stmt = null;
stmt = conn.createStatement();
rs = stmt.executeQuery(query);
while(rs.next()){
String name = rs.getString("name");
String company = rs.getString("company");
int salary = rs.getInt("salary");
System.out.println("Name: " + name + "\tCompany: " + company + "\tSalary: " + salary);
}
} catch (ClassNotFoundException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
But here we are passing the id directly. How can we pass it like parametrized queries (like how we pass ? during PreparedStatement)
in that case your query should be
String query = "select * from employee where id = ?";
instead of Statement you need to create PreparedStatement
PreparedStatement preparedStatement = conn.prepareStatement(query);
and then set your id to the prepared statement
preparedStatment.setInt(1, id);
finally execute the query
resultSet = preparedStatement.executeQuery();
It's old post but I would still like to add my answer.
I don't have enough reputation to comment on #prasad's answer, so I am adding small correction as separate answer. Actually, passing query inside praparedStatement.executeQuery() throws MySQLSyntaxErrorException because still it calls Statement.executeQuery instead of PreparedStatement.executeQuery(). And how do I know? I had to spent ample amount of time in figuring out this issue.
So use PreparedStatement.executeQuery() instead of PreparedStament.executeQuery(query).