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org.sqlite.SQLiteException: [SQLITE_NOTADB] File opened that is not a database file (file is encrypted or is not a database) [NETBEANS]

So i got this form that I'm using but I get that error whenever i submit, it says CONNECTION SUCCESSFUL but then it returns the error and never insert nor retrieves anything from the db. I checked the version of the sqlite and everything, can't figure it out.
public class databaseConnection {
public static Connection connection = null;
public static Connection getConnection() throws ClassNotFoundException {
try {
System.out.println("CONNECTING");
Class.forName("org.sqlite.JDBC");
connection = DriverManager.getConnection("jdbc:sqlite:SoftwareDB.db");
System.out.println("CONNECTION SUCCESSFUL");
} catch (SQLException e) {
System.out.println("ERROR: Connection Failed!");
}
return connection;
}
public static void login(String username, String password, String login) throws ClassNotFoundException {
try {
System.out.println("INSERTING");
try (Statement stmt = getConnection().createStatement()) {
String sql = "INSERT INTO login (username, password) VALUES ('" + username + "', '" + password + "', '" + login + "');";
stmt.execute(sql);
}
getConnection().close();
System.out.println("INSERT SUCCESSFUL");
} catch (SQLException ex) {
Logger.getLogger(Connection.class.getName()).log(Level.SEVERE, null, ex);
}
}
public static ResultSet getLoginDetails(String query) throws SQLException, ClassNotFoundException {
ResultSet rs;
try (PreparedStatement ps = getConnection().prepareStatement(query)) {
rs = ps.executeQuery();
ps.close();
getConnection().close();
}
return rs;
}
public static ResultSet getExistentDetails(String query) throws SQLException, ClassNotFoundException {
ResultSet rs;
try (PreparedStatement ps = getConnection().prepareStatement(query)) {
rs = ps.executeQuery();
getConnection().close();
}
return rs;
}
}
private void loginBtnMouseClicked(java.awt.event.MouseEvent evt) {
if (username.getText().isEmpty() || password.getText().isEmpty()) {
infoLabel.setVisible(true);
username.setText("");
password.setText("");
} else {
try {
databaseConnection.getLoginDetails("SELECT * FROM register WHERE email = '?' AND password = '?'");
String ts = new SimpleDateFormat("dd.MM.yyyy - HH.mm.ss").format(System.currentTimeMillis());
databaseConnection.login(username.getText(), password.getText(), ts);
JOptionPane.showMessageDialog(null, "Login succesful!");
new login().setVisible(true);
infoLabel.setVisible(true);
username.setText("");
password.setText("");
} catch (HeadlessException ex) {
JOptionPane.showMessageDialog(null, "Failed!");
} catch (SQLException | ClassNotFoundException ex) {
Logger.getLogger(login.class.getName()).log(Level.SEVERE, null, ex);
}
}
}
Output

I believe you have forgotten an important thing: properly preparing your PreparedStatement and opening/closing connections correctly.
Would you try the following rewritten getLoginDetails() method and take inspiration from it for the other methods?
public static ResultSet getLoginDetails(String query, String email, String password) throws SQLException, ClassNotFoundException {
ResultSet rs;
try (Connection conn = getConnection()) {
try (PreparedStatement ps = conn.prepareStatement(query)) {
ps.setString(1,email);
ps.SetString(2,password);
rs = ps.executeQuery();
// Do something with the ResultSet here or do not close the statement!
}
}
return rs; // should be something else! (as it could be already closed)
}
Then you certainly need to do something with the ResultSet! For example: check that the email/password combination exists in order to validate the login request.
Also, some important remarks and tips:
better check that the connection is valid after initialization using isValid(timeout)
think about a connection pool or at least some ways to reuse your connection(s)
eventually use existing tools (libraries like Apache) for your ORM (Object-Relation Mapping) and DAO (Database Access Object) layers. Actually, that's highly recommended.
closing a PreparedStatement will automatically close the associated ResultSet. Your code does not take that into account. Cf. https://docs.oracle.com/javase/8/docs/api/java/sql/ResultSet.html
Keep me posted!

Trying to show info from database into terminal

I'm trying to display a list of the names of people in the database from the terminal, but not sure about how I would go about this. Right now I'm using a prepared statement
public static void showNames() throws SQLException {
Statement stmt=null;
Connection conn=null;
try {
conn = DriverManager.getConnection(DB_URL, USER, PASS);
stmt = conn.createStatement();
} catch (SQLException e) {
e.printStackTrace();
}
String selectTable="SELECT * FROM userInfo;";
stmt.execute(selectTable);
}

You're close.
Below code is not a complete answer, but hopefully enough to get you moving in the direction of obtaining a complete answer. The below code is basically the code you posted with some modifications.
public static void showNames() throws SQLException {
Statement stmt = null;
ResultSet rs = null;
Connection conn = null;
String selectTable="SELECT * FROM userInfo;";
try {
conn = DriverManager.getConnection(DB_URL, USER, PASS);
stmt = conn.createStatement();
rs = stmt.executeQuery(selectTable);
while (rs.next()) {
Object obj = rs.getObject("name of column in database table USERINFO");
System.out.println(obj);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
if (conn != null) {
conn.close();
}
}
}
You didn't post the structure of database table USERINFO, so replace name of column in database table with the actual column name.
By the way, there are many examples of how to do this on the Internet, for example Processing SQL Statements with JDBC.

JDBC connection in Java with Eclipse ( when a method calling a method)

I'm trying to connect to my DB using JDBC. I wanted to make a method for connection and another method for selecting data. I am getting a red line in Eclipse on the 'Connection con = connectDB();' part. ( See also attached) Cany anyone give me advice?
public class DBJdbc {
//Statement stmt = null;
// connecting to DB
public void connectDB() {
//Connection con = null;
try {
Class.forName("com.mysql.cj.jdbc.Driver");
Connection con = DriverManager.getConnection("jdbc:mysql://****/SAC?useSSL=false&serverTimezone=UTC", "***", "***");
}
catch(SQLException e) {
e.printStackTrace();
}
catch(ClassNotFoundException e) {
e.printStackTrace();
}
}
// a method for selecting DB
public static void select() {
//connectDB();
String sql = "SELECT * from SAC_SUR";
try(Connection con = connectDB(); // I'm getting a red line here)
PreparedStatement pstmt = con.prepareStatement(sql)){
Statement stmt = con.createStatement();
ResultSet rs = stmt.executeQuery(sql);
while(rs.next()) {
int id = rs.getInt(1);
String name = rs.getString(2);
System.out.println("Id = " + id + "name = " + name);
} //while
} catch(SQLException e) {
System.out.println(e.getMessage());
}
}
red line here!!!

connectDB() method is of void type and not returning anything but when you are calling the method, you are assigning it to variable con. So you need to change the return type of connectDb to the Connection type.
public Connection connectDB() {
Connection con = null;
try {
Class.forName("com.mysql.cj.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://****/SAC?useSSL=false&serverTimezone=UTC", "***", "***");
}
catch(SQLException e) {
e.printStackTrace();
}
catch(ClassNotFoundException e) {
e.printStackTrace();
}
return con;
}

You are trying to call non-static method into the static area, which is not allowed in Java. So I made this method static and returning the database connection.
Please update the below method into your code. It will resolve your problem.
public static Connection connectDB() {
Connection con = null;
try {
Class.forName("com.mysql.cj.jdbc.Driver");
con = DriverManager.getConnection("jdbc:mysql://****/SAC?useSSL=false&serverTimezone=UTC", "", "");
} catch(SQLException e) {
e.printStackTrace();
} catch(ClassNotFoundException e) {
e.printStackTrace();
}
return con;
}

Trying to connect to a database in Eclipse ee

I have been trying this for a few hours now but with no success. I downloaded the JDBC driver and it shows that it is one of my referenced libraries under my Package Explorer in Eclipse but every time I try to run my code I get errors. My database is fine as I can change it and view it from the MySQL Command Line Client.
I actually followed a guides directions on how to do it, only replacing the information from their database to information about mine.
import java.sql.*;
public class FirstExample {
//JDBC Driver Name and Database URL
final static String JDBC_DRIVER = "com.mysql.jdbc.Driver";
final static String DB_URL = "jdbc:mysql://localhost/test_database";
//Database Credentials
static final String USER = "user_one";
static final String PASS = "User_one_password";
public static void main(String[] args) {
Connection conn = null;
Statement stmt = null;
try {
//Register JDBC Driver
Class.forName("com.mysql.jdbc.Driver");
//Open a Connection
System.out.println("Connecting to the Database...");
conn = DriverManager.getConnection(DB_URL, USER, PASS);
//Execute a Query
System.out.println("Creating Statement...");
stmt = conn.createStatement();
String sql;
sql = "SELECT * FROM user";
ResultSet rs = stmt.executeQuery(sql);
//Extract Data from Result Set
while (rs.next()) {
//Retrieve by Column Name
int id = rs.getInt("id");
String first = rs.getString("name");
//Display Values
System.out.print("ID: " + id);
System.out.println("Name: " + first);
}
//Clean Up Environment
rs.close();
stmt.close();
conn.close();
} catch (SQLException se) {
//Handle Errors For JDBC
se.printStackTrace();
} catch (Exception e) {
//Handle Errors for Class.forName
e.printStackTrace();
} finally {
//Finally Block used to close resources
try {
if (stmt != null)
stmt.close();
} catch (SQLException se2) {
//Nothing We Can Do
}
try {
if (conn != null)
conn.close();
} catch (Exception se) {
se.printStackTrace();
}//End Finally Try
}//End Try
System.out.println("Goodbye!");
}//End Main
}//End First Example
Here is the error I get http://pastebin.com/hLSxV3aq

SQL statements in Java function

I am using Java and MySQL.
I have two sql statement in two separate function, one create database, another create tables.
I try to write try & catch exception block in each function, it works, like code below.
public class j_sql1 {
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL = "jdbc:mysql://localhost";
static final String DB_URL2 = "jdbc:mysql://localhost/zxc";
static final String USER = "root";
static final String PASS = "";
static Connection conn = null;
static Statement stmt = null;
public static void create_db()
{
conn = null;
stmt = null;
try{
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection(DB_URL, USER, PASS);
stmt = conn.createStatement();
String sql = "CREATE DATABASE zxc";
stmt.executeUpdate(sql);
stmt.close();
conn.close();
}
catch(SQLException se){
se.printStackTrace();
}
catch(Exception e){
e.printStackTrace();
}
finally
{
try{
if(stmt!=null)
stmt.close();
}
catch(SQLException se2){}
try{
if(conn!=null)
conn.close();
}
catch(SQLException se){
se.printStackTrace();
}
}
}
public static void create_tables ()
{
conn = null;
stmt = null;
try{
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection(DB_URL2, USER, PASS);
stmt = conn.createStatement();
String sql = "CREATE TABLE ABC("+
"abc_ID int NOT NULL AUTO_INCREMENT,"+
"abc_Name varchar(50),"+
"PRIMARY KEY (abc_ID))";
stmt.executeUpdate(sql);
stmt.close();
conn.close();
}
catch(SQLException se){
se.printStackTrace();
}
catch(Exception e){
e.printStackTrace();
}
finally
{
try{
if(stmt!=null)
stmt.close();
}
catch(SQLException se2)
{}
try{
if(conn!=null)
conn.close();
}
catch(SQLException se){
se.printStackTrace();
}
}
}
public static void main(String[] args)
{
create_db();
create_tables();
}
}
But what if only one catch exception block in the main for my two try blocks in the two functions something like the code below, possible?
public class j_sql1 {
static final String JDBC_DRIVER = "com.mysql.jdbc.Driver";
static final String DB_URL = "jdbc:mysql://localhost";
static final String DB_URL2 = "jdbc:mysql://localhost/zxc";
static final String USER = "root";
static final String PASS = "";
static Connection conn = null;
static Statement stmt = null;
public static void create_db()
{
conn = null;
stmt = null;
try{
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection(DB_URL, USER, PASS);
stmt = conn.createStatement();
String sql = "CREATE DATABASE zxc";
stmt.executeUpdate(sql);
stmt.close();
conn.close();
}
}
public static void create_tables ()
{
conn = null;
stmt = null;
try{
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection(DB_URL2, USER, PASS);
stmt = conn.createStatement();
String sql = "CREATE TABLE ABC("+
"abc_ID int NOT NULL AUTO_INCREMENT,"+
"abc_Name varchar(50),"+
"PRIMARY KEY (abc_ID))";
stmt.executeUpdate(sql);
stmt.close();
conn.close();
}
}
public static void main(String[] args)
{
try
{
create_db();
create_tables();
}
catch(SQLException se){
se.printStackTrace();
}
catch(Exception e){
e.printStackTrace();
}
finally
{
try{
if(stmt!=null)
stmt.close();
}
catch(SQLException se2)
{}
try{
if(conn!=null)
conn.close();
}
catch(SQLException se){
se.printStackTrace();
}
}
}
}
And why the variable like Connection, Statement and the functions have to be declared to static?
Thank You.

In the static main, there is no object instance of the class j_sql1. Hence only static fields may be read.
You should do
Naming convention the same as 99.9 % of java users:
class JSql1
void createDB()
void createTables()
Instantiate an object, and call functions on it:
... main(...) {
JSql1 app = new JSql1();
try {
app.openConnection();
app.createDB();
app.createTables():
} catch (SQLException e) {
Logger.getLogger(JSql1.class.getName()).log(Level.FATAL, "...", e);
} finally {
app.close();
}
When createDB fails, there is no need to continue, hence createDB should throw the
exception.
Also the functions are uaseful inside a single connection, so create the connection
separately.
Design decision, but at least for statements declare all as locally as possible
Especially try-with-resource for automatically closing helps here
class JSql1;
Connection conn;
void createTables() throws SQLException {
try (Statement stmt = conn.createStatement()) {
String sql = "CREATE TABLE ABC(" +
"abc_ID int NOT NULL AUTO_INCREMENT," +
"abc_Name varchar(50)," +
"PRIMARY KEY (abc_ID))";
stmt.executeUpdate(sql);
}
}