在想要的时间java之后，计时器不会重新启动

Question

我有以下代码。我的问题是该程序只运行一次，即使我希望它每5秒运行一次。你能指导我搞错吗？

基本上，程序必须在数据库中检入最后两个条目，并在时间戳之间进行区分。

最后，如果通过的时间是必需的，则必须向用户发送消息。这应该连续运行，但我只能让它运行一次。

这是我的代码：

java.util.Timer timer = new java.util.Timer();

  public TimerChangeButtonBackground() {
     timer.schedule(new TimerTask(){
    public void run() 
        {


            try {
                 String DB_Connection = "jdbc:sqlserver://127.0.0.1:1433;databaseName=Dizertatie;instance=SQLServer;integratedSecurity=true;";
                Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
                final Connection conn = DriverManager.getConnection(DB_Connection);



                Statement state = conn.createStatement();

                ResultSet rs = state.executeQuery("set dateformat dmy; \n" +
"\n" +
"SELECT TOP 2 DIFF FROM  DIFF_CT ORDER BY Full_Time_Stamp DESC ");
                JOptionPanex.getRootFrame().dispose();
                if(rs.next()){
                    rs.next();
                    String value = rs.getString(1);
                    int difference = Integer.valueOf(value);

                    if (difference <= 5){

                    ImageIcon icon = new ImageIcon("C:\\Users\\Hory\\Desktop\\likegreen.png");
                JOptionPanex.showConfirmDialog(
                        null,
                        "Part in target",
                        "In Target", JOptionPanex.OK_CANCEL_OPTION,JOptionPanex.CANCEL_OPTION, icon);

                System.out.printf("target");
                }
                    else{

                     ImageIcon icon2 = new ImageIcon("C:\\Users\\Hory\\Desktop\\likered.png");
                JOptionPanex.showConfirmDialog(
                            null,
                        "Part NOT in target",
                        "Not in target",JOptionPanex.OK_CANCEL_OPTION,JOptionPanex.CANCEL_OPTION,icon2);
                    System.out.printf("NOtarget");
                    }

            }}catch(Exception e){

                System.out.println(e);
            }}},3,5000);  
     `