java - SQL错误java.lang.ArrayIndexOutOfBoundsException : 0

Question

private void jselectedhousecomboPopupMenuWillBecomeInvisible(javax.swing.event.PopupMenuEvent evt) {                                                                 

    String tmp = (String)jselectedhousecombo.getSelectedItem();
    String sql = "SELECT H.HOUSE, H.TOTALROOMS, H.BEDSPERROOM, H.ROOMSOCCUPIED, 
                         H.ROOMSAVAILABLE, HM.HM_ID, HM.HM_NAME, HM.HM_DEPARTMENT, 
                         HM.HOUSE, HM.HM_PHONENUMBER, HM.HM_DATEIN, HM.HM_DATEOUT, 
                         HM.HM_RESIDENCE, CA.C_ID, CA.C_NAME, CA.HOUSE, CA.C_PHONENUMBER,
                         CA.C_DATEIN, CA.C_DATEOUT, CA.C_RESIDENCE, HP.HP_REGNO,HP.HP_NAME, HP.HP_FORM,
                         HP.HOUSE,HP.HP_ROOMNO,HP.HP_DATE, HP.HP_DATEOUT    
                  FROM HOUSES H     
                  JOIN Housemaster HM 
                  ON H.HOUSE = HM.HOUSE JOIN Caretaker CA 
                  ON H.HOUSE = CA.HOUSE JOIN Houseprefect HP 
                  ON H.HOUSE = HP.HOUSE"; 

            try 
            {

                pst=conn.prepareStatement(sql);

                pst.setString(1, tmp);

                rs=pst.executeQuery();

            if(rs.next())
            {

                String add=rs.getString("HOUSE");
                jselectedhousename.setText(add);

                String add2=rs.getString("C_NAME");
                jselectedhousecaretaker.setText(add2);

                String add3=rs.getString("HM_NAME");
                jselectedhousemaster.setText(add3);

                String add4=rs.getString("HP_NAME");
                jselectedhouseprefect.setText(add4);

                String add5=rs.getString("TOTALROOMS");
                jselectedhousetr.setText(add5);

                String add6=rs.getString("BEDSPERROOM");
                jselectedhousebpr.setText(add6);

                String add7=rs.getString("ROOMSOCCUPIED");
                jselectedhousero.setText(add7);

                String add8=rs.getString("ROOMSAVAILABLE");
                jselectedhousera.setText(add8);

                String add9=rs.getString("HM_ID");
                jselectedhmid.setText(add9);

                String add10=rs.getString("HM_NAME");
                jselectedhmname.setText(add10);

                String add11=rs.getString("HM_DEPARTMENT");
                jselectedhmdept.setText(add11);

                String add12=rs.getString("HOUSE");
                jselectedhmhouse.setText(add12);

                String add13=rs.getString("HM_PHONENUMBER");
                jselectedhmphone.setText(add13);

                String add14=rs.getString("HM_DATEIN");
                jselectedhmdatein.setText(add14);

                String add15=rs.getString("HM_DATEOUT");
                jselectedhmdateout.setText(add15);

                String add16=rs.getString("HM_RESIDENCE");
                jselectedhmresidence.setText(add16);

                String add17=rs.getString("HP_REGNO");
                jselectedhpregno.setText(add17);

                String add18=rs.getString("HP_NAME");
                jselectedhpname.setText(add18);

                String add19=rs.getString("HP_FORM");
                jselectedhpform.setText(add19);

                String add20=rs.getString("HOUSE");
                jselectedhphouse.setText(add20);

                String add21=rs.getString("HP_ROOMNO");
                jselectedhproom.setText(add21);

                String add22=rs.getString("HP_DATEIN");
                jselectedhpdatein.setText(add22);

                String add23=rs.getString("HP_DATEOUT");
                jselectedhpdateout.setText(add23);

                String add24=rs.getString("C_ID");
                jselectedcid.setText(add24);

                String add25=rs.getString("C_NAME");
                jselectedcnames.setText(add25);

                String add26=rs.getString("HOUSE");
                jselectedchouse.setText(add26);

                String add27=rs.getString("C_PHONENUMBER");
                jselectedcphone.setText(add27);

                String add28=rs.getString("C_DATEIN");
                jselectedcdatein.setText(add28);

                String add29=rs.getString("C_DATEOUT");
                jselectedcdateout.setText(add29);

                String add30=rs.getString("C_RESIDENCE");
                jselectedcresidence.setText(add30);


            }
    } catch (Exception e) 
    {
        System.out.println(e);
        e.printStackTrace();
        JOptionPane.showMessageDialog(null, e);
    }
            finally
    {
        try {
            rs.close();
            pst.close();
        } catch (Exception e) {
        }
    }

    // TODO add your handling code here:
}

Answer 1

您试图在 SELECT 语句中返回太多行。如果 SELECT 语句内有一个 SELECT 语句，则它只能返回 1 行。

您需要将多个表连接在一起。我不知道你的表的确切架构，但如果我不得不猜测，我会说这就是你想要的:

SELECT H.HOUSE,H.TOTALROOMS,H.BEDSPERROOM,H.ROOMSOCCUPIED,H.ROOMSAVAILABLE,
       HM.ID,HM.NAME,HM.DEPARTMENT,HM.HOUSE,HM.PHONENUMBER,HM.DATEIN,HM.DATEOUT,HM.RESIDENCE,
       CA.ID,CA.NAME,CA.HOUSE,CA.PHONENUMBER,CA.DATEIN,CA.DATEOUT,CA.RESIDENCE,
       HP.REGNO,HP.NAME,HP.FORM,HP.HOUSE,HP.ROOMNO,HP.DATEIN,HP.DATEOUT 
FROM HOUSES H JOIN HOUSEMASTER HM  ON H.HOUSE = HM.ROWID 
              JOIN CARETAKER CA ON H.HOUSE = CA.ROWID 
              JOIN HOUSEPERFECT HP ON H.HOUSE = HP.ROWID; 

阅读this guide有关 SQL JOIN 语句的更多信息。