如何在使用Executor 和SwingWorker 進行多執行緒時取得ArrayIndexOutOfBoundsException
答案：
在 SwingWorker 的 done() 方法中重新拋出從 Future#get() 獲取的異常，可以使問題中的異常成為可能。
修改後的done() 方法如下所示：
透過在done() 方法中捕捉這些異常，SwingWorker 可以將它們重新拋出，以便在應用程式中處理異常。
@Override
protected void done() {
try {
get();
} catch (InterruptedException | ExecutionException | IllegalStateException e) {
e.printStackTrace();
}
}上述程式碼示範如何使用Executor 和SwingWorker 進行多線程，並透過在done() 方法中重新拋出異常，捕獲和處理ArrayIndexOutOfBoundsException 異常。
import java.awt.BorderLayout;
import java.awt.Dimension;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.beans.PropertyChangeEvent;
import java.beans.PropertyChangeListener;
import java.text.DateFormat;
import java.util.Date;
import java.util.List;
import java.util.concurrent.Executor;
import java.util.concurrent.Executors;
import java.util.concurrent.Future;
import javax.swing.*;
import javax.swing.table.*;
/** @see https://stackoverflow.com/questions/7054627 */
public class TableWithExecutor extends JFrame {
private static final int delay = 1000;
private static final DateFormat df = DateFormat.getTimeInstance();
private String[] columnNames = {"Product", "Availability"};
private Object[][] data = {columnNames, columnNames, columnNames};
private DefaultTableModel model;
private JTable table;
private Executor executor = Executors.newCachedThreadPool();
private Timer timer;
public TableWithExecutor() {
model = new DefaultTableModel(data, columnNames);
table = new JTable(model) {
@Override
public Class getColumnClass(int column) {
return getValueAt(0, column).getClass();
}
};
table.setDefaultRenderer(Date.class, new DefaultTableCellRenderer() {
@Override
protected void setValue(Object value) {
setText((value == null) ? "" : df.format(value));
}
});
table.setPreferredScrollableViewportSize(new Dimension(200, 100));
JScrollPane scrollPane = new JScrollPane(table);
add(scrollPane, BorderLayout.CENTER);
timer = new Timer(delay, startCycle());
timer.setRepeats(true);
timer.start();
}
private Action startCycle() {
return new AbstractAction(MyTask.STARTSCHEDULE) {
@Override
public void actionPerformed(ActionEvent e) {
executor.execute(new MyTask(MyTask.STARTSCHEDULE));
}
};
}
public static void main(String[] args) {
EventQueue.invokeLater(new Runnable() {
@Override
public void run() {
TableWithExecutor frame = new TableWithExecutor();
frame.setDefaultCloseOperation(EXIT_ON_CLOSE);
frame.pack();
frame.setLocationRelativeTo(null);
frame.setVisible(true);
}
});
}
private class MyTask extends SwingWorker<List<DateRecord>, DateRecord> {
private static final String STARTSCHEDULE = "StartSchedule";
private String name = STARTSCHEDULE;
MyTask(String name) {
this.name = name;
addPropertyChangeListener(new TaskListener(name));
}
@Override
protected List<DateRecord> doInBackground() throws Exception {
for (int row = 0; row < model.getRowCount(); row++) {
Date date = new Date();
date.setTime(date.getTime() + row * 1000);
publish(new DateRecord(row, date));
}
return null;
}
@Override
protected void process(List<DateRecord> chunks) {
for (DateRecord dr : chunks) {
model.setValueAt(dr.date, dr.rowNumber, 1);
}
}
@Override
protected void done() {
try {
get();
} catch (Exception e) {
e.printStackTrace(System.err);
}
}
}
private static class DateRecord {
private int rowNumber;
private Date date;
public DateRecord(int recordNumber, Date date) {
this.rowNumber = recordNumber;
this.date = date;
}
}
private static class TaskListener implements PropertyChangeListener {
private String name;
TaskListener(String name) {
this.name = name;
}
@Override
public void propertyChange(PropertyChangeEvent e) {
System.out.println(name + ": "
+ e.getOldValue() + " -> " + e.getNewValue());
}
}
}以上是使用Executor和SwingWorker進行多執行緒時如何捕捉ArrayIndexOutOfBoundsException？的詳細內容。更多資訊請關注PHP中文網其他相關文章！
