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Keep particular data in a JTable from database

I want to show particular data that keep one by one data in jtable, but never show all data,
private void jTextField1KeyReleased(java.awt.event.KeyEvent evt) {
String txt = jTextField1.getText().toString();
Connection cn = null;
PreparedStatement ps = null;
ResultSet rs = null;
try {
cn = Dataconnection.getConnection();
qr = "SELECT p.ProductCode,p.ProductName, p.ProductPrice FROM
customer.product p WHERE CONCAT(p.ProductCode, p.ProductName) LIKE '%"+txt+"%'";
ps=cn.prepareStatement(qr);
ps.setString(1, jTextField1.getText());
rs=ps.executeQuery();
jTable1.setModel(DbUtils.resultSetToTableModel(rs));
} catch (Exception e) {
e.printStackTrace();
}finally{
try {
rs.close();
ps.close();
} catch (Exception e) {
}
}
}

Inserting MySQL Java

I am having a problem with my mysql setBanned statement. I am trying to set a user banned into the database, but it is throwing me a "No operation is allowed after connection closed." can anyone help me?
It throws an error on the
statement.setString(3, reason);
In the setBanned code.
Current setBanned code:
public boolean setBanned(Player player, boolean state, String reason){
Connection conn = null;
PreparedStatement statement = null;
String setBanned = "INSERT INTO `test_bans` (UUID, BANNED, REASON) VALUES ( ?, ?, ?)";
String setUnbanned = "UPDATE `test_bans` SET BANNED= ? WHERE UUID= ?";
try{
conn = MySql.getConnection();
if(isBanned(player) && state == false){
statement = conn.prepareStatement(setUnbanned);
statement.setBoolean(1, state);
statement.setString(2, player.getUniqueId().toString());
statement.executeUpdate();
} else {
statement = conn.prepareStatement(setBanned);
statement.setString(1, player.getUniqueId().toString());
statement.setBoolean(2, state);
statement.setString(3, reason);
statement.executeUpdate();
}
} catch (SQLException e){
e.printStackTrace();
} finally {
if(statement != null){
try{
statement.close();
} catch (SQLException e){
e.printStackTrace();
}
}
if(conn != null){
try {
conn.close();
} catch (SQLException e){
e.printStackTrace();
}
}
}
return false;
}
isBanned code:
public boolean isBanned(Player player){
Connection conn = null;
PreparedStatement statement = null;
ResultSet result = null;
String query = "SELECT BANNED FROM `test_bans` WHERE UUID= ?";
try{
conn = MySql.getConnection();
statement = conn.prepareStatement(query);
statement.setString(1, player.getUniqueId().toString());
result = statement.executeQuery();
return result.next();
} catch (SQLException e){
e.printStackTrace();
} finally {
if (result != null){
try{
result.close();
} catch (SQLException e){
e.printStackTrace();
}
}
if(statement != null){
try{
statement.close();
} catch (SQLException e){
e.printStackTrace();
}
}
if(conn != null){
try {
conn.close();
} catch (SQLException e){
e.printStackTrace();
}
}
}
return false;
}
EDIT: MySQL Class
public class MySql {
private static String DATABASE_NAME ="testing_database";
private static String DATABASE_IP ="localhost:3306";
private static String connection ="jdbc:mysql://"+DATABASE_IP+"/"+DATABASE_NAME;
private static String username ="root";
private static String password ="pass";
private static Connection conn;
public static void handleConnection(){
Bukkit.getServer().getLogger().info("Establishing connection to MySQL Database....");
try{
conn = DriverManager.getConnection(connection, username, password);
if(!conn.isClosed()){
Bukkit.getServer().getLogger().info("Successfully synced with MySQL!");
return;
}
return;
}
catch (SQLException e){
e.printStackTrace();
return;
}
}
public static void disconnectConnection(){
Bukkit.getServer().getLogger().info("Disconnecting from MySQL Databse....");
try{
conn.close();
if(conn.isClosed()){
Bukkit.getServer().getLogger().info("Successfully Disconnected");
}
return;
}
catch(SQLException e){
e.printStackTrace();
return;
}
}
public static boolean setupTables(){
try{
System.out.println("Checking Tables");
conn.prepareStatement("CREATE TABLE IF NOT EXISTS test_ranks (UUID VARCHAR(255), RANK VARCHAR(25));").executeUpdate();
conn.prepareStatement("CREATE TABLE IF NOT EXISTS test_bans (UUID VARCHAR(255), BANNED BOOLEAN, REASON TEXT);").executeUpdate();
return true;
}
catch(SQLException e){
e.printStackTrace();
return false;
}
}
public static boolean checkConnection(){
try{
if((conn != null) && (!conn.isClosed())){
return true;
}
return false;
}
catch(SQLException e){
e.printStackTrace();
return false;
}
}
public static Connection getConnection(){
try {
if(conn.isClosed()){
connectMySQL();
return conn;
}
if(conn == null){
connectMySQL();
return conn;
}
} catch (SQLException e){
e.printStackTrace();
}
return conn;
}
public static void connectMySQL(){
try {
conn = DriverManager.getConnection(connection, username, password);
return;
} catch(SQLException e){
e.printStackTrace();
}
}
}

Your question is not clear....
There isn't any class MySql.If its custom class ...provide its code snippet.
Actual way of using Mysql JDBC connections
Class.forName("com.mysql.jdbc.Driver");
Connection conn = null;
conn = DriverManager.getConnection("jdbc:mysql://hostname:port/dbname","username", "password");
//Create statement
//Execute statement
//Iterate over results
//close statement
conn.close(); // close connection

in this line if(isBanned(player) && state == false){ you are calling the isBanned() and after that method executes the connection is closed in the line
conn.close();
in the isBannedMethod()
therefore when it comes to the else portion the connection is already closed.
You need to get another connection
Add
else {
**conn = MySql.getConnection();**
statement = conn.prepareStatement(setBanned);

ResultSet in Java

I need help creating a boolean check for a method I made. I basically want it to return true if they have the specified EnumRank, but it's not working. Any suggestions?
EDIT: Both values are stored in VARCHARS
Code:
public boolean hasRank(Player player, EnumRanks rank){
if (!MySql.checkConnection()){
return false;
}
try{
String query = "SELECT RANK FROM `user_ranks` WHERE UUID= '" + player.getUniqueId() + "';";
PreparedStatement statement = MySql.getConnection().prepareStatement(query);
ResultSet result = statement.executeQuery();
result.next();
return result.getBoolean(rank.getSQLName());
//return true - So I can use this method
}
catch (SQLException e){
//Nothing
}
return false;
}

Add the rank to the query, and you're using PreparedStatement so use bind parameters. You can use result.next() to check if the query returns a result and you should use the finally block to close your Statement and ResultSet (and Connection). And don't silently swallow Exception(s). Something like
public boolean hasRank(Player player, EnumRanks rank) {
if (!MySql.checkConnection()) {
return false;
}
Connection conn = null;
PreparedStatement statement = null;
ResultSet result = null;
String query = "SELECT RANK FROM `user_ranks` WHERE UUID=? AND RANK=?";
try {
conn = MySql.getConnection();
statement = conn.prepareStatement(query);
statement.setString(1, player.getUniqueId());
statement.setString(2, rank.getSQLName());
result = statement.executeQuery();
return result.next();
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (result != null) {
try {
result.close();
} catch (Exception e) {
e.printStackTrace();
}
}
if (statement != null) {
try {
statement.close();
} catch (Exception e) {
e.printStackTrace();
}
}
if (conn != null) {
try {
conn.close();
} catch (Exception e) {
e.printStackTrace();
}
}
}
return false;
}

Selecting a count from my database using Java and Netbeans

I have the following code:
try {
String sql = "SELECT COUNT(*) AS \"Jumlah\" FROM dokter";
ResultSet rs = connection.st.executeQuery(sql);
if(rs.next()){
abc = rs.getString("Jumlah").toString();
}
} catch (Exception e) {
System.out.println("\n Message: " + e.getMessage());
}
Why can't my ResultSet execute the given SQL?

Lose the alias, it's just an unnecessary complication. Just reference the ResultSet by the column's index:
try {
String sql = "SELECT COUNT(*) FROM dokter";
ResultSet rs = connection.st.executeQuery(sql);
if(rs.next()) {
abc = rs.getInt(1); // or getString(1) if you need it as a String
}
} catch (Exception e) {
System.out.println("\n Message: " + e.getMessage());
}

I suggest you use a PreparedStatement and a try-with-resources to close it (and your ResultSet). A count is not a String, and if you have a Connection connection then you might do something like
int count = 0;
try {
String sql = "SELECT COUNT(*) FROM dokter";
try (PreparedStatement ps = connection.prepareStatement(sql);
ResultSet rs = ps.executeQuery()) {
if (rs.next()) {
count = rs.getInt(1);
}
}
} catch (Exception e) {
e.printStackTrace();
} finally {
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}

"Operation not allowed after ResultSet closed" with Datasource and crawler4j

After reading through a lot of similar questions I have not been able to get a solution that works for me.
I have this methods:
In a crawler4j Controller I do this:
ArrayList<String> urls = Urls.getURLs(100);
for (String s : urls) {
System.out.println("Adding URL: " + s);
controller.addSeed(s);
}
this is getURLs():
public static ArrayList<String> getURLs(int number) {
ArrayList<String> list = new ArrayList<String>();
String getStatement = "select * from " + Configurations.getStringProperty("mysql.urls.db_name", "urls") + " where retrieved=0 limit "
+ Configurations.getStringProperty("mysql.urls.limit", "100") + ";";
ResultSet rs;
rs = Databaseclient.executeStatement(getStatement);
try {
while (rs.next()) {
list.add(rs.getString("url"));
// Databaseclient.executeStatement("update urls set retrieved = true where id = "
// + rs.getInt("id") + ";");
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
try {
rs.close();
} catch (SQLException e) {
// TODO Auto-generated catch block
e.printStackTrace();
}
}
return list;
}
This is my executeStatement():
public static ResultSet executeStatement(String s) {
Connection connection = null;
Statement statement = null;
ResultSet resultSet = null;
try {
// fetch a connection
connection = DataSource.getInstance().getConnection();
if (connection != null) {
statement = connection.createStatement();
resultSet = statement.executeQuery(s);
}
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
} catch (IOException e) {
System.out.println("A IOException occured executing the Statement");
e.printStackTrace();
} catch (PropertyVetoException e) {
System.out.println("A PropertyVetoException occured executing the Statement");
e.printStackTrace();
} finally {
if (resultSet != null) {
try {
resultSet.close();
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
}
}
if (statement != null) {
try {
statement.close();
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
}
}
if (connection != null) {
try {
connection.close();
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
}
}
}
return resultSet;
}
I get the error
java.sql.SQLException: Operation not allowed after ResultSet closed
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:1094)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:997)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:983)
at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:928)
at com.mysql.jdbc.ResultSetImpl.checkClosed(ResultSetImpl.java:799)
at com.mysql.jdbc.ResultSetImpl.next(ResultSetImpl.java:6982)
at database.Urls.getURLs(Urls.java:27)
at crawler.Controller.main(Controller.java:53)
Which is the line
while (rs.next()) {
in my getURLs() method.
What am I doing wrong? There is no code between getting the statement and the while loop that could close the statement.

Your code is a bit off, but if I understand you then don't close your ResultSet in the finally block of your executeStatement method.
public static ResultSet executeStatement(Connection connection,
Statement statement, String s) {
ResultSet resultSet = null;
try {
if (statement != null) {
resultSet = statement.executeQuery(s);
}
} catch (SQLException e) {
System.out.println("A SQLException occured executing the Statement");
e.printStackTrace();
} catch (IOException e) {
System.out.println("A IOException occured executing the Statement");
e.printStackTrace();
} catch (PropertyVetoException e) {
System.out.println("A PropertyVetoException occured executing the Statement");
e.printStackTrace();
}
return resultSet;
}
Then you need to pass in a Connection and Statement, and you'll get a ResultSet back. Also, the caller should then close all three when it's done with the ResultSet.