在巨大的数据负载下对JTable行选择事件的延迟响应 [英] Delayed response to JTable row selection event under a huge data load

问题描述

我有一个Swing JTable 使用大量数据动态更新 - 新行不断添加，几分钟内可添加1000-2000行。我已经注册了一个Listener来响应使用的单行选择事件来执行一些工作人员。我已经使用Observer模式进行Swing数据绑定，而表的模型由WritableList实现支持。因此，新项目将从其自己的Realm添加到表中。并且从SWT UI线程添加了Listener。
问题是，当新行添加到表时，它不会立即响应用户行选择事件。只有在停止更新表格模型时，表格才会响应用户选择 - 有时会延迟30-60秒。
请帮助我，以及为什么我的表模型在深度更新时不会立即响应用户选择，以及如何克服此限制。
任何建议都将受到赞赏。

I have a Swing JTable dynamically updated with a big amount of data—new rows are live added constantly, and some 1000-2000 rows can be added during a few minutes. I have registered a Listener to reponse for use's single row selection event to perform some staff. I have used Observer pattern for Swing data binding and table's model is backed by a WritableList implementation. So new items are added to the table from its own Realm. And Listener was added from the SWT UI thread. The problem is, that when new rows are added to table, it doesn't respond at once on user row selection event. Only when stop updating table model, table will respond on user selection- some times with delay more then 30-60 seconds. Please, help me undersand why my table model doesn't respond at once to user selection when intensively updated, and how to overcome this limitation. Any suggestions will be appreciated.

推荐答案

使用 SwingWorker publish（） 您的行在后台并在的实现中更新 TableModel 过程（）。 SwingWorker 将限制更新至可持续的费率。 个人资料，以确保您不会阻止事件派遣线程。

Use SwingWorker to publish() your rows in the background and update the TableModel in your implementation of process(). SwingWorker will limit updates to a sustainable rate. Profile to ensure that you are not blocking the event dispatch thread.

附录：GUI仍然响应这个1,000,000-行测试变体。分析时，请注意每次单击开始按钮都会启动一个新工作程序。

Addendum: The GUI remains responsive with this 1,000,000-row variation, as tested. When profiling, note that each click of the "Go" button starts a new worker.

import java.awt.BorderLayout;
import java.awt.Component;
import java.awt.EventQueue;
import java.awt.event.ActionEvent;
import java.text.DateFormat;
import java.text.SimpleDateFormat;
import java.util.ArrayList;
import java.util.Arrays;
import java.util.Date;
import java.util.List;
import javax.swing.AbstractAction;
import javax.swing.JButton;
import javax.swing.JFrame;
import javax.swing.JScrollPane;
import javax.swing.JTable;
import javax.swing.SwingWorker;
import javax.swing.table.AbstractTableModel;
import javax.swing.table.DefaultTableCellRenderer;

/** @see https://stackoverflow.com/a/17415635/230513 */
public class TestTableLoad01 {

    public static void main(String[] args) {
        new TestTableLoad01();
    }

    public TestTableLoad01() {
        EventQueue.invokeLater(new Runnable() {
            @Override
            public void run() {
                final MyTableModel model = new MyTableModel();
                JTable table = new JTable(model);
                table.setDefaultRenderer(Date.class, new TimeCellRenderer());

                JFrame frame = new JFrame("Testing");
                frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
                frame.setLayout(new BorderLayout());
                frame.add(new JScrollPane(table));
                frame.pack();
                frame.setLocationRelativeTo(null);
                frame.setVisible(true);
                frame.add(new JButton(new AbstractAction("Go") {
                    @Override
                    public void actionPerformed(ActionEvent e) {
                        TableSwingWorker worker = new TableSwingWorker(model);
                        worker.execute();
                    }
                }), BorderLayout.SOUTH);
            }
        });
    }

    public class TimeCellRenderer extends DefaultTableCellRenderer {

        private DateFormat df;

        public TimeCellRenderer() {
            df = new SimpleDateFormat("HH:mm:ss");
        }

        @Override
        public Component getTableCellRendererComponent(JTable table,
            Object value, boolean isSelected, boolean hasFocus, int row, int column) {

            if (value instanceof Date) {

                value = df.format(value);

            }

            super.getTableCellRendererComponent(table, value, isSelected, hasFocus, row, column);

            return this;

        }
    }

    public class MyTableModel extends AbstractTableModel {

        private String[] columnNames = new String[]{"Date", "Row"};
        private List<RowData> data;

        public MyTableModel() {
            data = new ArrayList<RowData>(25);
        }

        @Override
        public Class<?> getColumnClass(int columnIndex) {
            return columnIndex == 0 ? Date.class : Integer.class;
        }

        @Override
        public String getColumnName(int col) {
            return columnNames[col];
        }

        @Override
        public int getColumnCount() {
            return columnNames.length;
        }

        @Override
        public int getRowCount() {
            return data.size();
        }

        @Override
        public Object getValueAt(int row, int col) {
            RowData value = data.get(row);
            return col == 0 ? value.getDate() : value.getRow();
        }

        public void addRow(RowData value) {
            int rowCount = getRowCount();
            data.add(value);
            fireTableRowsInserted(rowCount, rowCount);
        }

        public void addRows(RowData... value) {
            addRows(Arrays.asList(value));
        }

        private void addRows(List<RowData> rows) {
            int rowCount = getRowCount();
            data.addAll(rows);
            fireTableRowsInserted(rowCount, getRowCount() - 1);
        }
    }

    public class RowData {

        private Date date;
        private int row;

        public RowData(int row) {
            this.date = new Date();
            this.row = row;
        }

        public Date getDate() {
            return date;
        }

        public int getRow() {
            return row;
        }
    }

    public class TableSwingWorker extends SwingWorker<MyTableModel, RowData> {

        private final MyTableModel tableModel;

        public TableSwingWorker(MyTableModel tableModel) {
            this.tableModel = tableModel;
        }

        @Override
        protected MyTableModel doInBackground() throws Exception {

            // This is a deliberate pause to allow the UI time to render
            Thread.sleep(1000);

            System.out.println("Start polulating");

            for (int index = 0; index < 1000000; index++) {

                RowData data = new RowData(index);
                publish(data);
                Thread.yield();
            }
            return tableModel;
        }

        @Override
        protected void process(List<RowData> chunks) {
            System.out.println("Adding " + chunks.size() + " rows");
            tableModel.addRows(chunks);
        }
    }
}

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