Java Swing AbstractTableModel-IndexOutOfBounds 删除行时异常

Question

我正在做一个 Swing 项目。可能，它太大了，不能粘贴在这里。我甚至尝试记录一个table.getSelectedRow((，它显示了一个正确的索引。但是不知何故，当我按下删除按钮时，这会导致在此类中调用的 remove 方法，selectedRow 更改为 -1，并且我得到一个 IndexOutOfBoundsException。请帮忙。这是CarTableModelClass：

import javax.swing.table.AbstractTableModel;
import java.util.LinkedList;
public class CarTableModel extends AbstractTableModel {
public LinkedList<Car> cars=new LinkedList<Car>();
@Override
public int getRowCount() {
    return cars.size();
}
@Override
public int getColumnCount() {
    return 4;
}
@Override
public Object getValueAt(int row, int column){
    if((row>cars.size()-1) || (column>3) ){
        return null;
    }
    else {
        Car targetCar=cars.get(row);
        switch (column){
            case 0: {return targetCar.brand;}
            case 1: {return targetCar.year;}
            case 2: { return targetCar.volume;}
            case 3: {return targetCar.maxSpeed;}
            default: {return null; }
        }
    }
}
@Override
public Class<?> getColumnClass(int columnIndex){
    switch (columnIndex){
        case 0: {return String.class;}
        case 1: {return Integer.class;}
        case 2: { return Double.class;}
        case 3: {return Double.class;}
        default: {return Object.class; }
    }
}
@Override
public String getColumnName(int columnIndex){
    switch (columnIndex){
        case 0: {return "Brand";}
        case 1: {return "Year";}
        case 2: { return "Volume";}
        case 3: {return "Max Speed";}
        default: {return null; }
    }
}

@Override
public boolean isCellEditable(int rowIndex, int columnIndex){
    return false;
}
public void addRow(Car value)
{
    if(value!=null) {
        cars.add(value);
        fireTableDataChanged();
    }
}
public void update(int index, Car car){
    if((car!=null) &&(index>=0)&& (index<(cars.size()-1))){
        cars.set(index,car);
        fireTableRowsUpdated(index,index+1);
    }
}
public void remove(int index){
    if((cars!=null) &&(index>=0)&& (index<(cars.size()-1))){
        cars.remove(index);
        fireTableRowsDeleted(index,index+1);
    }
}
}

以下是我得到的例外：

Exception in thread "AWT-EventQueue-0" java.lang.IndexOutOfBoundsException: Index: -1, Size: 10
at java.util.LinkedList.checkElementIndex(LinkedList.java:555)
at java.util.LinkedList.get(LinkedList.java:476)
at CarTableModel.getValueAt(CarTableModel.java:26)
at MainWindow.lambda$new$0(MainWindow.java:51)
at javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:184)
at javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:164)
at javax.swing.DefaultListSelectionModel.fireValueChanged(DefaultListSelectionModel.java:211)
at javax.swing.DefaultListSelectionModel.removeIndexInterval(DefaultListSelectionModel.java:677)
at javax.swing.JTable.tableRowsDeleted(JTable.java:4509)
at javax.swing.JTable.tableChanged(JTable.java:4412)
at javax.swing.table.AbstractTableModel.fireTableChanged(AbstractTableModel.java:296)
at javax.swing.table.AbstractTableModel.fireTableRowsDeleted(AbstractTableModel.java:261)
at CarTableModel.remove(CarTableModel.java:83)
at Toolbar.actionPerformed(Toolbar.java:45)
at javax.swing.AbstractButton.fireActionPerformed(AbstractButton.java:2022)
at javax.swing.AbstractButton$Handler.actionPerformed(AbstractButton.java:2348)
at javax.swing.DefaultButtonModel.fireActionPerformed(DefaultButtonModel.java:402)
at javax.swing.DefaultButtonModel.setPressed(DefaultButtonModel.java:259)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(BasicButtonListener.java:252)
at java.awt.Component.processMouseEvent(Component.java:6535)
at javax.swing.JComponent.processMouseEvent(JComponent.java:3324)
at java.awt.Component.processEvent(Component.java:6300)
at java.awt.Container.processEvent(Container.java:2236)
at java.awt.Component.dispatchEventImpl(Component.java:4891)
at java.awt.Container.dispatchEventImpl(Container.java:2294)
at java.awt.Component.dispatchEvent(Component.java:4713)
at java.awt.LightweightDispatcher.retargetMouseEvent(Container.java:4888)
at java.awt.LightweightDispatcher.processMouseEvent(Container.java:4525)
at java.awt.LightweightDispatcher.dispatchEvent(Container.java:4466)
at java.awt.Container.dispatchEventImpl(Container.java:2280)
at java.awt.Window.dispatchEventImpl(Window.java:2750)
at java.awt.Component.dispatchEvent(Component.java:4713)
at java.awt.EventQueue.dispatchEventImpl(EventQueue.java:758)
at java.awt.EventQueue.access$500(EventQueue.java:97)
at java.awt.EventQueue$3.run(EventQueue.java:709)
at java.awt.EventQueue$3.run(EventQueue.java:703)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:86)
at java.awt.EventQueue$4.run(EventQueue.java:731)
at java.awt.EventQueue$4.run(EventQueue.java:729)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$JavaSecurityAccessImpl.doIntersectionPrivilege(ProtectionDomain.java:76)
at java.awt.EventQueue.dispatchEvent(EventQueue.java:728)
at java.awt.EventDispatchThread.pumpOneEventForFilters(EventDispatchThread.java:201)
at java.awt.EventDispatchThread.pumpEventsForFilter(EventDispatchThread.java:116)
at java.awt.EventDispatchThread.pumpEventsForHierarchy(EventDispatchThread.java:105)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:101)
at java.awt.EventDispatchThread.pumpEvents(EventDispatchThread.java:93)
at java.awt.EventDispatchThread.run(EventDispatchThread.java:82)
-1

UPD：这是第 51 行的 lambda：

  table.getSelectionModel().addListSelectionListener((event)->
    {
        int row=table.getSelectedRow();
        formPanel.setSelectedRow(row);
        toolbar.setSelectedRow(row);
        System.out.println(row);
        formPanel.fill(
                model.getValueAt(row,0),
                model.getValueAt(row,1),
                model.getValueAt(row,2),
                model.getValueAt(row,3)
        );
    });

问题是，我无法阻止它返回 -1。

Answer 1

看起来该行已被 CarTableModel.remove 成功删除，但随后这调用了 fireTableRowsDeleted ，这反过来又调用了 MainWindow 中的某个方法，然后调用CarTableModel.getValueAt，但是由于该行已被删除，它会抛出异常。您已经测试了太大的行或列的值，然后从该方法返回而不执行任何操作。如果您还测试负值，是否一切正常？

或者，正如@JBNeizet所说，MainWindow第 51 行的方法可以测试负值，然后不调用 CarTableModel.getValueAt ，但如果从多个位置调用getValueAt那么在方法本身中进行参数验证是有意义的。