java - 如何从另一个组件的监听器为 JTable 设置表模型？

Question

我创建了两个 JPanel。一个 JPanel 有一个带有节点的 JTree。另一个 JPanel 有一个 SQL 填充的 JTable。我正在尝试从 JTree 中获取节点选择，以使用 JTree 的输入重新运行 JTable 的查询，为 JTable 提供部分过滤器。你能提供指导吗？我是 Java 的新手。这是问题的代码:

import java.awt.BorderLayout;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.Hashtable;
import javax.swing.JFrame;
import javax.swing.JPanel;
import javax.swing.JScrollPane;
import javax.swing.JSplitPane;
import javax.swing.JTable;
import javax.swing.JTree;
import javax.swing.ScrollPaneConstants;
import javax.swing.event.TreeSelectionEvent;
import javax.swing.event.TreeSelectionListener;
import javax.swing.table.DefaultTableModel;
import javax.swing.tree.DefaultMutableTreeNode;
import javax.swing.tree.TreeSelectionModel;

public class SCCEEforTreeAndTableInteraction {

    private static Connection conn = null;
    private static Statement stmt = null;
    private static ResultSet rs = null;
    private static ResultSetMetaData meta;
    private static int columnCount = 0;
    private static int rowCount = 0;
    private static Object[][] result;
    private static String[] columnNames;
    private static JTree tree;
    public static Hashtable<Object, Integer> treeData;
    public int tableTopicNodeID;

    public static void main(String[] args) {

        //Create and setup window
        JFrame frame = new JFrame("Tree and Table Interaction");
        JPanel panelMain = new JPanel(new BorderLayout());
        JPanel treePanel = new JPanel(new BorderLayout());
        JPanel tablePanel = new JPanel(new BorderLayout());
        JSplitPane split = new JSplitPane(JSplitPane.HORIZONTAL_SPLIT, treePanel, tablePanel);
        split.setOneTouchExpandable(true);
        myJTree tree = new myJTree();
        myJTable table = new myJTable();
        frame.add(panelMain);
        treePanel.add(tree);
        tablePanel.add(table);
        panelMain.add(split);
        frame.setVisible(true);
        panelMain.setVisible(true);
        treePanel.setVisible(true);
        tablePanel.setVisible(true);
        frame.pack();

    }

    private static class myJTable extends JPanel {
        //Getting the data from the database in order to fill the table
        public myJTable() {
            try {
                conn = DriverManager.getConnection("jdbc:derby://localhost:1527/FlamingDartDB;create=true;user=user;password=password");
                stmt = conn.createStatement(ResultSet.TYPE_SCROLL_INSENSITIVE, ResultSet.CONCUR_UPDATABLE);

                rs = stmt.executeQuery("select count(*) from FLAMINGDART.TOPICDATA where NODEID =" + *Start with a default, then get data from the listener below*); //NodeID should be different every time I select a node
                rs.beforeFirst();
                while (rs.next()) {
                    rowCount = rs.getInt(1);
                }
                rs = stmt.executeQuery("select * from FLAMINGDART.TOPICDATA where NODEID =3");//NodeID should be different every time I select a node
                meta = rs.getMetaData();
                columnCount = meta.getColumnCount();   //The first 2 column are not for display to the user
                columnNames = new String[columnCount];
                for (int i = 0; i < columnCount; i++) {
                    columnNames[i] = meta.getColumnName(i + 1);
                }
                result = new Object[rowCount][columnCount];
                rs.beforeFirst();
                for (int i = 0; i < rowCount; i++) {
                    rs.next();
                    for (int j = 0; j < columnCount; j++) {
                        result[i][j] = rs.getObject(j + 1);
                    }
                }
                stmt.close();
                conn.close();
            } catch (SQLException sqlExcept) {
                sqlExcept.printStackTrace();
            }
            DefaultTableModel tableModel = new DefaultTableModel(result, columnNames);
            JTable table = new JTable(tableModel);
            JScrollPane topicTableScrollPane = new JScrollPane(table);
            topicTableScrollPane.setHorizontalScrollBarPolicy(ScrollPaneConstants.HORIZONTAL_SCROLLBAR_NEVER);
            add(topicTableScrollPane);
        }
    }

    private static class myJTree extends JPanel implements TreeSelectionListener {

        public myJTree() {
            //This is sample tree data with the node ID that is used to refine the table query.
            treeData = new Hashtable();
            treeData.put("Node 1", new Integer(1));
            treeData.put("Node 2", new Integer(2));
            treeData.put("Node 3", new Integer(3));
            treeData.put("Node 4", new Integer(4));
            treeData.put("Node 5", new Integer(5));
            treeData.put("Node 6", new Integer(6));
            treeData.put("Node 7", new Integer(7));
            treeData.put("Node 8", new Integer(8));
            treeData.put("Node 9", new Integer(9));
            tree = new JTree(treeData);
            tree.getSelectionModel().setSelectionMode(TreeSelectionModel.SINGLE_TREE_SELECTION);
            tree.addTreeSelectionListener(this);
            this.add(tree);
        }

        @Override
        public void valueChanged(TreeSelectionEvent tse) {
            DefaultMutableTreeNode nodeSelected = (DefaultMutableTreeNode) tree.getLastSelectedPathComponent();
            if (nodeSelected == null) //Nothing is selected.     
            {
                System.out.println("Selected Node is Null");
                return;
            }
            Integer n = treeData.get(nodeSelected.getUserObject());//Returns the integer value associated with the key from the node table
            if (n != null) {
                System.out.println("Start a new query with " + n + " as a filter for the query.");
 *//This is supposed to set the node id that helps populate the table with a new query. Something along the lines of table.SetTableModel(n) that I'm having trouble implementing.*
            }
        }
    }
}

Answer 1

在您的 TreeSelectionListener 中，使用 SwingWorker 的实例在后台更新您的 JTable 的 TableModel。可以找到更多示例 here和 here .