UCanAccess异常：​​无法从ResultSet获取getMetaData（游标状态无效）

Question

我正在尝试从Access表中获取数据并在JTable上显示它。我正在使用UCanAccess，因为Java 8不支持JDBC-ODBC。

我的窗口类调用充电方法：

ctrlGestionVentas= new CtrlGestionVentas();
ctrlGestionVentas.cargarListaVentas(tblListaVentas);

然后，CtrlGestionVentas.cargarListaVentas（tabla）从ResultSet填充JTable：

public class CtrlGestionVentas {

public void cargarListaVentas(JTable tabla) {

    ResultSet rs;
    DataVentas dv = new DataVentas();
    rs = dv.getListaVentas();
    try {
            tabla.setModel(buildTableModel(rs));
            RowSorter sorter = new TableRowSorter(buildTableModel(rs));
            tabla.setRowSorter(sorter);
            tabla.getTableHeader().setDefaultRenderer(new MultiSortTableCellHeaderRenderer());
    } catch (SQLException e) {
        // TODO Auto-generated catch block
        e.printStackTrace();
    }

}


public static DefaultTableModel buildTableModel(ResultSet rs)
        throws SQLException {

    ResultSetMetaData metaData = rs.getMetaData(); /*THIS IS THE LINE WHICH APPARENTLY PROVOKES THE ERROR*/

    // names of columns

    Vector<String> columnNames = new Vector<String>();
    int columnCount = metaData.getColumnCount();
    for (int column = 1; column <= columnCount; column++) {
        columnNames.add(metaData.getColumnName(column));
    }

    // data of the table

    <Vector<Object>> data = new Vector<Vector<Object>>();
    while (rs.next()) {
        Vector<Object> vector = new Vector<Object>();
        for (int columnIndex = 1; columnIndex <= columnCount; columnIndex++) {
            vector.add(rs.getObject(columnIndex));
        }
        data.add(vector);
    }

    return new DefaultTableModel(data, columnNames);

}

}

这是DataVentas类中的ResultSet getter方法（注意：FactoryConexion具有ConnectionString，在本文中已经省略）：

public class DataVentas {
    public ResultSet getListaVentas() {
        PreparedStatement stmt=null;
        ResultSet rs=null;
        try {

            stmt = FactoryConexion.getInstancia().getConn().prepareStatement("select * from ventasfinal");
            rs = stmt.executeQuery();
        } catch (SQLException ex) {

                System.out.println("SQLException: " + ex.getMessage());

        }
        finally{
            try {
                if (rs!=null)
                    rs.close();
                if (stmt!=null)stmt.close();                
            } catch (SQLException e) {
                e.printStackTrace();
            }
        }
        return rs;
    }

}

当我执行时，我得到以下内容：

net.ucanaccess.jdbc.UcanaccessSQLException: UCAExc:::3.0.6 estado del cursor incorrecto: cursor indicado no está abierto
    at net.ucanaccess.jdbc.UcanaccessResultSet.getMetaData(UcanaccessResultSet.java:480)
    at negocio.CtrlGestionVentas.buildTableModel(CtrlGestionVentas.java:37)
    at negocio.CtrlGestionVentas.cargarListaVentas(CtrlGestionVentas.java:22)
    at ui.GestionVentas.<init>(GestionVentas.java:85)
    at ui.GestionVentas$1.run(GestionVentas.java:63)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at 
java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)

Caused by: java.sql.SQLException: estado del cursor incorrecto: cursor indicado no está abierto
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCResultSet.checkClosed(Unknown Source)
    at org.hsqldb.jdbc.JDBCResultSet.getMetaData(Unknown Source)
    at net.ucanaccess.jdbc.UcanaccessResultSet.getMetaData(UcanaccessResultSet.java:478)
    ... 18 more

Caused by: org.hsqldb.HsqlException: estado del cursor incorrecto: cursor indicado no está abierto
    at org.hsqldb.error.Error.error(Unknown Source)
    at org.hsqldb.error.Error.error(Unknown Source)
    ... 22 more

net.ucanaccess.jdbc.UcanaccessSQLException: UCAExc:::3.0.6 estado del cursor incorrecto: cursor indicado no está abierto
    at net.ucanaccess.jdbc.UcanaccessResultSet.getMetaData(UcanaccessResultSet.java:480)
    at negocio.CtrlVendedores.buildTableModel(CtrlVendedores.java:38)
    at negocio.CtrlVendedores.cargarListaVendedores(CtrlVendedores.java:23)
    at ui.GestionVentas.<init>(GestionVentas.java:95)
    at ui.GestionVentas$1.run(GestionVentas.java:63)
    at java.awt.event.InvocationEvent.dispatch(Unknown Source)
    at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
    at java.awt.EventQueue.access$500(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.awt.EventQueue$3.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at 
java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(Unknown Source)
    at java.awt.EventQueue.dispatchEvent(Unknown Source)
    at java.awt.EventDispatchThread.pumpOneEventForFilters(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForFilter(Unknown Source)
    at java.awt.EventDispatchThread.pumpEventsForHierarchy(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.pumpEvents(Unknown Source)
    at java.awt.EventDispatchThread.run(Unknown Source)

Caused by: java.sql.SQLException: estado del cursor incorrecto: cursor indicado no está abierto
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCUtil.sqlException(Unknown Source)
    at org.hsqldb.jdbc.JDBCResultSet.checkClosed(Unknown Source)
    at org.hsqldb.jdbc.JDBCResultSet.getMetaData(Unknown Source)
    at 
net.ucanaccess.jdbc.UcanaccessResultSet.getMetaData(UcanaccessResultSet.java:478)
    ... 18 more

Caused by: org.hsqldb.HsqlException: estado del cursor incorrecto: cursor indicado no está abierto
    at org.hsqldb.error.Error.error(Unknown Source)
    at org.hsqldb.error.Error.error(Unknown Source)
    ... 22 more

请注意，调试器中标记的最后一行是buildTableModel方法（rs.getMetaData（））中的一行。这是怎么回事？

谢谢你的时间！

Answer 1

获取ResultSet的方法，然后在finally块中关闭它。因此，您根本无法使用该ResultSet。您必须重新组织代码。