java - No operations allowed after connection closed MYSQL

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Basically I have:
String query = "SELECT * FROM table WHERE UNIQUEID=? AND DIR IS NOT NULL AND NAME IS NOT NULL AND PAGETYPE IS NOT NULL";
DBConnect Database = new DBConnect();
Connection con = null;
PreparedStatement ps = null;
ResultSet rs=null;
try {
    con = Database.getcon();
    ps = con.prepareStatement(query);
    ps.setString(1, URI);
    rs=ps.executeQuery();
    if(rs.next()){
} finally {
    if(ps != null)
        ps.close();
    if(rs != null)
        rs.close();
    if(con != null)
        con.close();
query = "SELECT COUNTCOMMENTS FROM videosinfos WHERE UNIQUEID=?";
try {
    con = Database.getcon();
    ps = con.prepareStatement(query); // Getting error here
    rs=ps.executeQuery();
    ps.setString(1, URI);
    rs=ps.executeQuery();
    if(rs.next()){
        comments = rs.getInt(1);
} finally {
    if(ps != null)
        ps.close();
    if(rs != null)
        rs.close();
    if(con != null)
        con.close();
Note: The line I get the error, have a comment on it.
Connecting to Database:
public DBConnect(){
        Class.forName("com.mysql.jdbc.Driver");
        String unicode="useSSL=false&autoReconnect=true&useUnicode=yes&characterEncoding=UTF-8";
        con = DriverManager.getConnection("jdbc:mysql://localhost:15501/duckdb?"+unicode, "root", "_PWD");
        st = con.createStatement();
    }catch(Exception ex){
        System.out.println(ex.getMessage());
        System.out.println("couldn't connect!");
public Connection getcon(){
    DBConnect condb = new DBConnect();
    Connection connect = con;
    return con;
But in compilation I get this error:
  com.mysql.jdbc.exceptions.jdbc4.MySQLNonTransientConnectionException: No operations allowed after connection closed.
      at sun.reflect.GeneratedConstructorAccessor18.newInstance(Unknown Source)
      at sun.reflect.DelegatingConstructorAccessorImpl.newInstance(DelegatingConstructorAccessorImpl.java:45)
      at java.lang.reflect.Constructor.newInstance(Constructor.java:423)
      at com.mysql.jdbc.Util.handleNewInstance(Util.java:404)
      at com.mysql.jdbc.Util.getInstance(Util.java:387)
      at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:917)
      at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:896)
      at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:885)
      at com.mysql.jdbc.SQLError.createSQLException(SQLError.java:860)
      at com.mysql.jdbc.ConnectionImpl.throwConnectionClosedException(ConnectionImpl.java:1246)
      at com.mysql.jdbc.ConnectionImpl.checkClosed(ConnectionImpl.java:1241)
      at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4102)
      at com.mysql.jdbc.ConnectionImpl.prepareStatement(ConnectionImpl.java:4071)
      at duck.reg.pack.DBConnect.getitemfull_details(DBConnect.java:686)
      at duck.reg.pack.index.doPost(index.java:73)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:661)
      at javax.servlet.http.HttpServlet.service(HttpServlet.java:742)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:231)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
      at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
      at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:193)
      at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:166)
      at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)
      at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)
      at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:478)
      at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)
      at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:80)
      at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624)
      at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)
      at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:342)
      at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:799)
      at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)
      at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:868)
      at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1455)
      at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)
      at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1149)
      at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:624)
      at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)
      at java.lang.Thread.run(Thread.java:748)
I'm Using Debian with MariaDB v10.x/Mysql
Connection is closed after the execution of first PreparedStatement
getcon uses an instance variable instead of local variable. Due to this, same conn variable (the one that was closed earlier) gets returned when getcon is called next time.
To fix this, getcon and DBConnect need to be modified to declare a local conn variable and return it (in fact, you don't need DBConnect at all), e.g.:
public Connection getcon(){
        Class.forName("com.mysql.jdbc.Driver");
        String unicode="useSSL=false&autoReconnect=true&useUnicode=yes&characterEncoding=UTF-8";
        return DriverManager.getConnection("jdbc:mysql://localhost:15501/duckdb?"+unicode, "root", "_PWD");
    }catch(Exception ex){
        System.out.println(ex.getMessage());
        System.out.println("couldn't connect!");
        throw new RuntimeException(ex);
                JDBC standard doesn't close connection after first PreparedStatement. This only should happen after close() or error condition: docs.oracle.com/javase/7/docs/api/java/sql/Connection.html
– Dimon Buzz
                Aug 18, 2018 at 6:21
This is a MySQL settings issue. The response time of the MySQL server (60,621 ms in the example above) exceeds the MySQL server's configured wait_timeout value. 
Solution
To resolve this issue, work with the MySQL database administrator to increase the value of the wait_timeout parameter. 
Align Hibernate Configuration with you MySQL server to fix this problem.
This setting is configurable in the my.cnf file. By default, mysql sets this value to "28800" seconds. If this value has been modified from the default, consider reverting it back to the default to restore connectivity to the Datameer server.
A good approach is to use one try - finally  block like this
String query = "SELECT * FROM table WHERE UNIQUEID=? AND DIR IS NOT NULL AND NAME IS NOT NULL AND PAGETYPE IS NOT NULL";
        DBConnect Database = new DBConnect();
        Connection con = null;
        PreparedStatement ps = null;
        ResultSet rs=null;
        try {
            con = Database.getcon();
            ps = con.prepareStatement(query);
            ps.setString(1, URI);
            rs=ps.executeQuery();
            if(rs.next()){
            query = "SELECT COUNTCOMMENTS FROM videosinfos WHERE UNIQUEID=?";
            ps = con.prepareStatement(query); // Getting error here
            rs=ps.executeQuery();
            ps.setString(1, URI);
            rs=ps.executeQuery();
            if(rs.next()){
                comments = rs.getInt(1);
        } finally {
            if(ps != null)
                ps.close();
            if(rs != null)
                rs.close();
            if(con != null)
                con.close();
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