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Java - [SQLITE_BUSY] The database file is locked (database is locked)

I had a java app with mysql connection but i had to transfer my database to sqlite from mysql because of mysql can not be embedded, i have the connection but i get this exception when i am using the app.
org.sqlite.SQLiteException: [SQLITE_BUSY] The database file is locked (database is locked)
I learnt this is a common mistake but i tried most of the answers however couldn't solve. The problem is i have about 30 different methods with void type or return types like these 2 for example below; (I call these methods on my swing app later)
I have these at start of my class;
private Connection con = null;
private Statement statement = null;
private PreparedStatement preparedstatement = null;
Methods for example;
public int lastPlaceProgram(){
String query= "Select * from userprogram where laststayed = 1";
try {
statement = con.createStatement();
ResultSet rs = statement.executeQuery(query);
int programid = 0;
while(rs.next()){
programid = rs.getInt("programid");
}
return programid;
} catch (SQLException ex) {
Logger.getLogger(Operations.class.getName()).log(Level.SEVERE, null, ex);
return 0;
}
}
or
public String programType(int programid){
String query = "Select * from programs where id = ?";
try {
preparedStatement = con.prepareStatement(query);
preparedStatement.setInt(1, programid);
ResultSet rs = preparedStatement.executeQuery();
String type = "";
while(rs.next()){
type = rs.getString("type");
}
return type;
} catch (SQLException ex) {
Logger.getLogger(Operations.class.getName()).log(Level.SEVERE, null, ex);
return null;
}
}
And constructor;
public Operations() {
String url = "jdbc:sqlite:C://Users//Me//Desktop//sqlited/trying.db";
try {
con = DriverManager.getConnection(url);
} catch (SQLException ex) {
Logger.getLogger(Operations.class.getName()).log(Level.SEVERE, null, ex);
}
}
I tried to add these finally block to after catch blocks of all my 30 methods;
finally{
try{
con.close();
} catch(Exception e){
}
}
But it didn't work, it gave Connection is closed mistake this time. I also tried to add preparedstatement.close(); to this finally block but didn't still work.

Finally blocks didn't work for me, i closed them manually if i had that variable to close. I mean if i used ResultSet and PreparedStatement at a method then i made rs.close() and preparedstatement.close() just before catch or before return. If i just had Preparedstatement variable on the method then i just did preparedstatement.close() before catch block or before return.

How to get a String from a field

I've got a mysql question within java. I've got a mysql database with different tables. I currently got a database called 'litebans' and a table called 'litebans_mutes'.
Within that table there is a row called reason and under that reason (let's say what's within reason) there's a string called 'This is a test' and 'sorry'; how would I get the string 'This is a test' and 'sorry' associated with the same 'uuid' row in java? Here is a picture explaining more:
Here is an image explaining the sql format
Additionally, i've currently initialized all variables and such in java, i currently have this code:
http://hastebin.com/odumaqazok.java (Main class; using it for a minecraft plugin)
The below code is the MySQL class; api used to connect and execute stuff.
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import net.octopusmc.punish.Core;
public class MySQL {
public static Connection openConnection() {
try {
Class.forName("com.mysql.jdbc.Driver");
} catch (ClassNotFoundException e1) {
System.err.println(e1);
e1.printStackTrace();
}
try {
Connection conn = DriverManager.getConnection("jdbc:mysql://" + Core.host + ":" + Core.port + "/" + Core.database, Core.user, Core.pass);
System.out.println("Currently connected to the database.");
return conn;
} catch (SQLException e) {
System.out.println("An error has occured while connecting to the database");
System.err.println(e);
e.printStackTrace();
}
return null;
}
public static void Update(String qry) {
try {
Statement stmt = Core.SQLConn.createStatement();
stmt.executeUpdate(qry);
stmt.close();
} catch (Exception ex) {
openConnection();
System.err.println(ex);
}
}
public static Connection getConnection() {
return Core.SQLConn;
}
public static ResultSet Query(String qry) {
ResultSet rs = null;
try {
Statement stmt = Core.SQLConn.createStatement();
rs = stmt.executeQuery(qry);
} catch (Exception ex) {
openConnection();
System.err.println(ex);
}
return rs;
}
}
An example using that api above is shown below:
try {
ResultSet rs = MySQL.Query("QUERY GOES HERE");
while (rs.next()) {
//do stuff
}
} catch (Exception err) {
System.err.println(err);
err.printStackTrace();
}
tl;dr: I want to get the two fields called 'reason' with the give 'uuid' string field.

First , make sure that your using the jdbc mysql driver to connect to the database
Defile a class where you could write the required connection and create statement code.
For example
class ConnectorAndSQLStatement {
ResultSet rs = null;
public Statement st = null;
public Connection conn = null;
public connect() {
try {
final String driver = "com.mysql.jdbc.Driver";
final String db_url = "jdbc:mysql://localhost:3306/your_db_name";
Class.forName(driver);//Loading jdbc Driver
conn = DriverManager.getConnection(db_url, "username", "password");
st = conn.createStatement();
rs = st.executeQuery("Select what_you_want from your_table_name");
while (rs.next()) {
String whatever = rs.getInt("whatever ");
System.out.print(whatever);
}
} catch (SQLException se) {
se.printStackTrace();
} catch (Exception e) {
e.printStackTrace();
}
Just call this function and the magic :D
Hope it is helpful

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

java.sql.SQLException: Invalid handle

I'm trying to teach myself how to connect to a msaccess database in java.
I have set up a class to access the database as follows
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.SQLException;
public abstract class AccessDBConnect2 {
public static Connection connect(){
String fileName = "C:/Users/Bridget/Documents/EmployeeSys.accdb";
Connection con = null;
try {
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver");
String url = "jdbc:odbc:Driver={Microsoft Access Driver (*.mdb, *.accdb)};DBQ="+fileName;
con = DriverManager.getConnection(url,"","");
} catch (Exception e) {
// Handle exceptions ...
System.out.println(e.toString());
System.out.println("A problem accessing the database");
e.printStackTrace();
} finally {
try { if(con!=null) {con.close();} } catch (Exception e) {}
}
return con;
}
public static void closeConnection(Connection conn){
try{
conn.close();
}catch (Exception e){
}
}
Then I have my code which is just trying to select everything from the table.
I have created the table in msAccess and the code seems to get through the connect method in the above code without any problems, indicating it is finding the database and accessing it somewhat. The problem happens when I call the prepareStatement using the connection, i.e. code line:
stm = conn.prepareStatement(sql);
The full code is:
import java.sql.*;
public class Program2{
public static void main(String[] args) {
try{
// Load the JDBC driver
Class.forName("sun.jdbc.odbc.JdbcOdbcDriver").newInstance();
// Establishing db connection
Connection conn = AccessDBConnect.connect();
// Displaying all records from employee file
System.out.println("Display records of all employees");
display(conn);
// Closing the connection
AccessDBConnect.closeConnection(conn);
}catch (Exception e){
System.out.println("Error");
}
}
// Display details of all employees
public static void display(Connection conn){
PreparedStatement stm = null;
// SQL statement
String sql = "SELECT * FROM Employee";
ResultSet rs;
try {
stm = conn.prepareStatement(sql); // Prepare the SQL statement
rs = stm.executeQuery(); // Execture the SQL statement
// Navigate through the ResultSet and print
while (rs.next()){
int id = rs.getInt("id");
String name = rs.getString("name");
String gender = rs.getString("gender");
String address = rs.getString("address");
System.out.println("ID: \t \t" + id);
System.out.println("Name: \t \t" + name);
System.out.println("Gender: \t" + gender);
System.out.println("Address: \t" + address);
System.out.println(" ");
}
// Closing the resultSet
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
public void test(){
int a = "hello";
}
}

You are receiving the error because when you try to call .prepareStatement the connection is closed. Your AccessDBConnect2 class contains a finally block that closes the connection before it returns. Fix that class so it leaves the connection open.
By the way, the JDBC-ODBC Bridge has been removed from Java 8 and is effectively obsolete. You might be interested in this alternative:
Manipulating an Access database from Java without ODBC

I've removed the obviously incorrect answer :) another possibility:
I would think the issue is in your connection to the database, try changing 'C:/Users/Bridget/Documents/EmployeeSys.accdb' to 'C:\\Users\Bridget\Documents\EmployeeSys.accdb'

Java database application

Can someone help me with this: I'm making a java database application and I want to put my methods for select,insert,update and delete into separated class so they can be called from another classes and reused.
Till now I managed to separate only methods for update and delete and for insert when not using prepared statement. Problem I'm encountering is how to return data's when doing select from database and put them into table.
Here are my update and delete method's in Queries class:
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import com.Konekcija.Konekcija;
public class Queries {
Konekcija konekcija = new Konekcija();
public void updateTable(String sqlQuery){
Connection conn = null;
Statement st = null;
try{
Class.forName("com.mysql.jdbc.Driver");
conn = konekcija.getConn();
st = conn.createStatement();
st.executeUpdate(sqlQuery);
}catch(Exception e){
e.printStackTrace();
}finally{
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
try {
st.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
public void deleteFromTable(String sqlQuery){
Connection conn = null;
Statement st = null;
try{
Class.forName("com.mysql.jdbc.Driver");
conn = konekcija.getConn();
st = conn.createStatement();
st.executeUpdate(sqlQuery);
}catch(Exception e){
e.printStackTrace();
}finally{
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
try {
st.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
}
P.S. Connection properties are in another class "Konekcija"

You should create a collection and populate it with the results of the query, it should look something like:
List<Foo> selectFoos(Connection connection) throws SQLException {
PreparedStatement ps = connection.prepareStatement("select * from foo");
try {
ResultSet resultSet = ps.executeQuery();
try {
List<Foo> foos = new ArrayList<Foo>();
while (resultSet.next()) {
Foo foo = new Foo();
// use resultSet methods get... to retrieve data from current row of results
// and populate foo
foos.add(foo);
}
} finally {
resultSet.close();
}
} finally {
ps.close();
}
return foos;
}

try executeQuery method. in the java doc for "resultset" class you will find a example:
http://docs.oracle.com/javase/6/docs/api/java/sql/ResultSet.html

Return data for "select from table" would be ResultSet.
You may return the ResultSet to caller and get values (or)
Inside the "Select" method of Queries class retrieve the data from resultset and set it some VO object and add this VO to collection and return the collection (assuming you will get more than one row in ResultSet). For example if you are querying User table, create Java bean class "User" with get/set methods. Set retrieved values to this bean and return it.
//Create User class with get/set in some package.
Class.forName("com.mysql.jdbc.Driver");
conn = konekcija.getConn();
st = conn.createStatement();
ResultSet rs=st.execute(sqlQuery);
//Instantiate user class
while (rs.next())
System.out.println("Name= " + rs.getString("moviename") + " Date= " + String fName = rs.getString("firstName");
User myUser = new User();
myUser.setFirstName(fName);
}
NOTE: This code is hand typed. There may be syntax errors. Please use it as starting point.