删除行的JTable导致ArrayOutofBounds异常-1

Question

我已经浏览了很多关于这方面的网站，并尝试了一些不同的东西，但我被难住了。如果能提供帮助，我将不胜感激。检查复选框是否选中（true）的条件正在工作，但我一执行model.removeRow（row），就会出现此错误。

public class ExpenditurePanel extends JPanel implements TableModelListener{
private static final long serialVersionUID = 1L;
private static TableModel1 model;
private JTable table;
public ExpenditurePanel() {
    model = new TableModel1();
    table = new JTable(model);
    table.setBorder(new BevelBorder(BevelBorder.LOWERED, null, null, null, null));
    table.setRowSelectionAllowed(false);
    table.setFillsViewportHeight(true);
    table.setCellSelectionEnabled(true);
    table.setColumnSelectionAllowed(false);
    model.addColumn("Name");
    model.addColumn("Week");
    model.addColumn("Fortnight");
    model.addColumn("Month");
    model.addColumn("Year");
    model.addColumn("Remove");
    Object[] default1 = {"Accomodation","","","","",false};
    Object[] default2 = {"Food","","","","",false};
    model.addRow(default1);
    model.addRow(default2);
    model.addTableModelListener(this);
    this.add(new JScrollPane(table));
    table.setRowSorter(null);
}
public static TableModel1 getModel(){
    return model;
}
@Override
public void tableChanged(TableModelEvent e) {
    int row = e.getFirstRow();
    int column = e.getColumn();
    model = (TableModel1) e.getSource();
    String columnName = model.getColumnName(column);
    Object data = model.getValueAt(row, column);
    if(model.getValueAt(row,column) == Boolean.TRUE){
        System.out.println("Condition working");
        //this part keeps giving me error.
        model.removeRow(row);
    }
}
}

这就是它抛出的：

Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: -1
at java.util.Vector.elementData(Unknown Source)
at java.util.Vector.elementAt(Unknown Source)
at javax.swing.table.DefaultTableModel.getValueAt(Unknown Source)
at studentBudget.ExpenditurePanel.tableChanged(ExpenditurePanel.java:53)
at javax.swing.table.AbstractTableModel.fireTableChanged(Unknown Source)
at javax.swing.table.AbstractTableModel.fireTableRowsDeleted(Unknown Source)
at javax.swing.table.DefaultTableModel.removeRow(Unknown Source)
at studentBudget.ExpenditurePanel.tableChanged(ExpenditurePanel.java:59)
at javax.swing.table.AbstractTableModel.fireTableChanged(Unknown Source)
at javax.swing.table.AbstractTableModel.fireTableCellUpdated(Unknown Source)
at javax.swing.table.DefaultTableModel.setValueAt(Unknown Source)
at javax.swing.JTable.setValueAt(Unknown Source)
at javax.swing.JTable.editingStopped(Unknown Source)
at javax.swing.AbstractCellEditor.fireEditingStopped(Unknown Source)
at javax.swing.DefaultCellEditor$EditorDelegate.stopCellEditing(Unknown Source)
at javax.swing.DefaultCellEditor.stopCellEditing(Unknown Source)
at javax.swing.DefaultCellEditor$EditorDelegate.actionPerformed(Unknown Source)
at javax.swing.AbstractButton.fireActionPerformed(Unknown Source)
at javax.swing.AbstractButton$Handler.actionPerformed(Unknown Source)
at javax.swing.DefaultButtonModel.fireActionPerformed(Unknown Source)
at javax.swing.JToggleButton$ToggleButtonModel.setPressed(Unknown Source)
at javax.swing.plaf.basic.BasicButtonListener.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at javax.swing.plaf.basic.BasicTableUI$Handler.repostEvent(Unknown Source)
at javax.swing.plaf.basic.BasicTableUI$Handler.mouseReleased(Unknown Source)
at java.awt.AWTEventMulticaster.mouseReleased(Unknown Source)
at java.awt.Component.processMouseEvent(Unknown Source)
at javax.swing.JComponent.processMouseEvent(Unknown Source)
at java.awt.Component.processEvent(Unknown Source)
at java.awt.Container.processEvent(Unknown Source)
at java.awt.Component.dispatchEventImpl(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.LightweightDispatcher.retargetMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.processMouseEvent(Unknown Source)
at java.awt.LightweightDispatcher.dispatchEvent(Unknown Source)
at java.awt.Container.dispatchEventImpl(Unknown Source)
at java.awt.Window.dispatchEventImpl(Unknown Source)
at java.awt.Component.dispatchEvent(Unknown Source)
at java.awt.EventQueue.dispatchEventImpl(Unknown Source)
at java.awt.EventQueue.access$000(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$1.doIntersectionPrivilege(Unknown Source)
at java.security.ProtectionDomain$1.doIntersectionPrivilege(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.awt.EventQueue$4.run(Unknown Source)
at java.security.AccessController.doPrivileged(Native Method)
at java.security.ProtectionDomain$1.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)

Answer 1

您正在更改TableModelListener内部的TableModel，这对我来说似乎有点风险，而且存在不必要的递归风险。如果可能的话，我会重新考虑你的代码，以免这样做。如果你仍然被卡住，那么你应该创建并发布一个ssce。

---

编辑1

如果我用你的代码进行ssce并添加println语句：

import javax.swing.*;
import javax.swing.border.BevelBorder;
import javax.swing.event.*;
import javax.swing.table.*;
public class ExpenditurePanel extends JPanel implements TableModelListener {
   private static final long serialVersionUID = 1L;
   private static TableModel1 model;
   private JTable table;
   public ExpenditurePanel() {
      model = new TableModel1();
      table = new JTable(model);
      table.setBorder(new BevelBorder(BevelBorder.LOWERED, null, null, null,
            null));
      table.setRowSelectionAllowed(false);
      table.setFillsViewportHeight(true);
      table.setCellSelectionEnabled(true);
      table.setColumnSelectionAllowed(false);
      model.addColumn("Name");
      model.addColumn("Week");
      model.addColumn("Fortnight");
      model.addColumn("Month");
      model.addColumn("Year");
      model.addColumn("Remove");
      Object[] default1 = { "Accomodation", "", "", "", "", false };
      Object[] default2 = { "Food", "", "", "", "", false };
      model.addRow(default1);
      model.addRow(default2);
      model.addTableModelListener(this);
      this.add(new JScrollPane(table));
      table.setRowSorter(null);
   }
   public static TableModel1 getModel() {
      return model;
   }
   @Override
   public void tableChanged(TableModelEvent e) {
      int row = e.getFirstRow();
      int column = e.getColumn();
      // **** printf added below
      System.out.printf("[row: %d, column: %d]%n", row, column);
      model = (TableModel1) e.getSource();
      String columnName = model.getColumnName(column);
      // **** println added below
      System.out.println("columnName: " + columnName);
      Object data = model.getValueAt(row, column);
      if (model.getValueAt(row, column) == Boolean.TRUE) {
         System.out.println("Condition working");
         // *** AIOOBE called here
         model.removeRow(row);
      }
   }
   public static void main(String[] args) {
      SwingUtilities.invokeLater(new Runnable() {
         public void run() {
            ExpenditurePanel panel = new ExpenditurePanel();
            JFrame frame = new JFrame("foo");
            frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
            frame.getContentPane().add(panel);
            frame.setLocationRelativeTo(null);
            frame.pack();
            frame.setVisible(true);
         }
      });
   }
}
// **** no idea how close this is to your code *****
class TableModel1 extends DefaultTableModel {
   @Override
   public Class<?> getColumnClass(int columnIndex) {
      if (getRowCount() == 0) {
         return super.getColumnClass(columnIndex);
      }
      Object value = getValueAt(0, columnIndex);
      if (value == null) {
         return super.getColumnClass(columnIndex);
      }
      return value.getClass();
   }
}

---

我得到这个输出：

[row: 0, column: 5]
columnName: Remove
Condition working
[row: 0, column: -1]
columnName: 
Exception in thread "AWT-EventQueue-0" java.lang.ArrayIndexOutOfBoundsException: -1
    at java.util.Vector.elementAt(Unknown Source)
    ...... etc ......

因此，您可以看到模型侦听器的tableChanged(...)方法被调用了两次，这是由于在侦听器内部更改侦听对象时发生了递归，第二次调用时，它有一列-1，这会导致抛出AIOOBE。

---

编辑2
一个潜在的解决方案是在对模型进行更改之前删除侦听器，然后在进行更改后重新添加侦听器：

public void tableChanged(TableModelEvent e) {
  int row = e.getFirstRow();
  int column = e.getColumn();
  System.out.printf("[row: %d, column: %d]%n", row, column);
  model = (TableModel1) e.getSource();
  String columnName = model.getColumnName(column);
  System.out.println("columnName: " + columnName);
  Object data = model.getValueAt(row, column);
  if (model.getValueAt(row, column) == Boolean.TRUE) {
     System.out.println("Condition working");
     model.removeTableModelListener(this);
     model.removeRow(row);
     model.addTableModelListener(this);
  }
}

Answer 2

详细说明@Hover的正确跟踪，并假设一个有效的用例，如"我们有一个作业列表，如果完成了一个，则将其从列表中删除"：

侦听器的基本问题是，它不会检查通知它的更改类型：您只对特定列的更新感兴趣，而对导致第二次通知错误的任何其他列（如删除行）都不感兴趣：类型为removed的modelEvent的列为-1

解决方案是添加检查，如果触发器不是特定列的更新，则不执行任何操作：

@Override
public void tableChanged(TableModelEvent e) {
    if (!TableUtilities.isUpdate(e)) return;
    ...  
}

分析TableModelEvent有点不方便（不是完全直观的条件，需要彻底阅读TableModelEvent javadoc）-我太懒了，无法将其保存在内存中，所以SwingX中有一个实用程序类，为了方便起见，将相关部分复制到这里：

/**
 * Returns a boolean indication whether the event represents a
 * dataChanged type.
 * 
 * @param e the event to examine.
 * @return true if the event is of type dataChanged, false else.
 */
public static boolean isDataChanged(TableModelEvent e) {
    if (e == null)
        return false;
    return e.getType() == TableModelEvent.UPDATE && e.getFirstRow() == 0
            && e.getLastRow() == Integer.MAX_VALUE;
}
/**
 * Returns a boolean indication whether the event represents a
 * update type.
 * 
 * @param e the event to examine.
 * @return true if the event is a true update, false
 *         otherwise.
 */
public static boolean isUpdate(TableModelEvent e) {
    if (isStructureChanged(e))
        return false;
    return e.getType() == TableModelEvent.UPDATE
            && e.getLastRow() < Integer.MAX_VALUE;
}
/**
 * Returns a boolean indication whether the event represents a
 * insert type.
 * 
 * @param e the event to examine
 * @return true if the event is of type insert, false otherwise.
 */
public static boolean isInsert(TableModelEvent e) {
    if (e == null) return false;
    return TableModelEvent.INSERT == e.getType();
}

/**
 * Returns a boolean indication whether the event represents a
 * structureChanged type.
 * 
 * @param e the event to examine.
 * @return true if the event is of type structureChanged or null, false
 *         else.
 */
public static boolean isStructureChanged(TableModelEvent e) {
    return e == null || e.getFirstRow() == TableModelEvent.HEADER_ROW;
}

Answer 3

只要这样：

clsController.getTable().setSortable( false );
model.removeRow( selectedModelRow );
clsController.getTable().setSortable( true );

它起作用了！

Answer 4

您可以检查其事件类型。这样，您可以跳过tableChanged方法的内容进行添加和删除。

public void tableChanged(TableModelEvent e) {
    int type = e.getType();
    if (type != TableModelEvent.DELETE && type != TableModelEvent.INSERT) {
    // operation only for update
    }
}