Aplikacija u napisana u swingu ima meni u kome stoje Connect i Disconnect. Pored toga imam u meniju i Show Table Users. Kad klikenem na Show Table Users on mi izbaci tabelu s korisnicima koje pokupi iz baze. Kad onda idem na Disconnect, pa opet na Connect i probam ponovo da pozovem Show Table Users on mi jevlja SQL exception "Connection is closed". Ovo su metode:
Code:
public static void connect() {
if(conn==null) {
try {
//login data
String userName = "sa";
String password = "";
//driver loading
Class.forName("org.hsqldb.jdbcDriver");
//url specification
String url = "jdbc:hsqldb:/home/ivan/MyBookstore/MyBookstore";
//getting connection
conn = DriverManager.getConnection(url, userName, password);
//setting Connection state
connState = true;
System.out.println("Database connection OPENED");
if(conn.isClosed()) {System.out.println("CLOSSSSEEEES"); }
} catch (Exception e)
{
System.out.println("Cannot connect to database server --> " + e);
}
}
else {
System.out.println("Allredy Connected");
}
}
//DISCONNECT Method
public static void disconnect() {
System.out.println("Database Connection CLOSED");
try {
stmt = conn.createStatement();
stmt.execute("SHUTDOWN");
stmt.close();
conn.close();
stmt=null;
conn =null;
connState=false;
} catch(SQLException e) {
connState=false;
stmt=null;
conn =null;
System.out.println("Disconnecting ERROR:\t" + e);
}
}
public static void connect() {
if(conn==null) {
try {
//login data
String userName = "sa";
String password = "";
//driver loading
Class.forName("org.hsqldb.jdbcDriver");
//url specification
String url = "jdbc:hsqldb:/home/ivan/MyBookstore/MyBookstore";
//getting connection
conn = DriverManager.getConnection(url, userName, password);
//setting Connection state
connState = true;
System.out.println("Database connection OPENED");
if(conn.isClosed()) {System.out.println("CLOSSSSEEEES"); }
} catch (Exception e)
{
System.out.println("Cannot connect to database server --> " + e);
}
}
else {
System.out.println("Allredy Connected");
}
}
//DISCONNECT Method
public static void disconnect() {
System.out.println("Database Connection CLOSED");
try {
stmt = conn.createStatement();
stmt.execute("SHUTDOWN");
stmt.close();
conn.close();
stmt=null;
conn =null;
connState=false;
} catch(SQLException e) {
connState=false;
stmt=null;
conn =null;
System.out.println("Disconnecting ERROR:\t" + e);
}
}