我需要帮助从我的数据库中检索表名，然后将其解析为 JCombobox，当单击表名时，将执行 sql 语句，然后在 JTable 中显示表。
我的问题是如何对 selectedItem 进行编码，以便它将执行查询并在 JTable 上显示 IT
这是我的 gui.java 文件
package Assignment3.Live;
import java.awt.*;
import java.awt.event.ActionEvent;
import java.awt.event.ActionListener;
import java.io.FileOutputStream;
import java.io.ObjectOutputStream;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.ResultSetMetaData;
import java.sql.SQLException;
import java.util.ArrayList;
import java.util.Vector;
import javax.swing.*;
import javax.swing.border.TitledBorder;
import javax.swing.event.TableModelEvent;
import javax.swing.table.DefaultTableModel;
import javax.swing.table.JTableHeader;
import javax.swing.table.TableColumn;
import javax.swing.table.TableColumnModel;
import javax.swing.table.TableModel;
import net.proteanit.sql.DbUtils;
;
/**
* @author jmickey
*
*/
public class GUI extends JFrame {
// Variables
public Main main;
DBCon db;
MakeTable make;
private JFrame frame = new JFrame();
private JPanel pNorth, pChooser, pdp, pRC, pSCR, pTab, pSouth, pBtn;
public ResultSet rseTo = null;// result set
public PreparedStatement pst = null;
private ResultSetMetaData meta = null;
String tableNamesnow = "";
private JMenuBar jMenuBar;
private JMenu file, help;
private JComboBox<String> jcmb = new JComboBox<String>();
ComboBoxModel<?> giveMeTableName = (ComboBoxModel<?>) jcmb
.getSelectedItem();
private JTable jT = new JTable();
private JTextArea text;
private JButton search, clear, displayRow, deletRow, addRow, query, save,
restore;
private JCheckBox rowS = new JCheckBox("Select by Rows", true);
private JCheckBox colS = new JCheckBox("Selcet by Column", false);
/*
* private String[] columnNames = {}; private Object [][] rowData = {};
*/
public GUI() throws SQLException {
GUInterface();
getTableNames();
arrayOfTable();
}
public void GUInterface() {// constructor
// Menubar
setLayout(new BorderLayout(5, 10));
jcmb.setSelectedItem("");
jMenuBar = new JMenuBar();
file = new JMenu("File");
file.add(new JMenuItem("Start"));
file.add(new JMenuItem("Exit"));
help = new JMenu("Help");
help.add(new JMenuItem("Help"));
jMenuBar.add(file);
jMenuBar.add(help);
// Button
save = new JButton("Save");
clear = new JButton("Clear");
restore = new JButton("Restore");
displayRow = new JButton("Display Row");
deletRow = new JButton("Delet Row");
addRow = new JButton("Add New Row");
query = new JButton("QUERY");
// choose table panel = 1
pChooser = new JPanel();
pChooser.setLayout(new BorderLayout(5, 0));
pChooser.setBorder(new TitledBorder("Tables"));
pChooser.add(new JLabel("Select a table: "), BorderLayout.WEST);
pChooser.add(jcmb, BorderLayout.CENTER);
// Row/Column selection Panel = 2
pRC = new JPanel();
pRC.setLayout(new FlowLayout(FlowLayout.LEFT));
pRC.add(rowS);
pRC.add(colS);
// noth panel holds (pChooser & pRC)
pNorth = new JPanel();
pNorth.setLayout(new GridLayout(2, 1));
pNorth.add(pChooser);
pNorth.add(pRC);
// JTable panel
pTab = new JPanel();
pTab.setLayout(new GridLayout(1, 1));
pTab.add(jT);
pTab.add(new JScrollPane(jT));
// display holds (pNorth & pTab)
pdp = new JPanel();
pdp.setLayout(new BorderLayout(2, 1));
pdp.add(pNorth, BorderLayout.NORTH);
pdp.add(pTab, BorderLayout.SOUTH);
// Save, Clear or restore Panel
pSCR = new JPanel();
pSCR.add(save);
pSCR.add(clear);
pSCR.add(restore);
// Button selection panel
pBtn = new JPanel();
pBtn.setLayout(new GridLayout(2, 2));
pBtn.add(displayRow);
pBtn.add(addRow);
pBtn.add(query);
pBtn.add(deletRow);
// South panel (pSCR & pBtn)
pSouth = new JPanel();
pSouth.setLayout(new BorderLayout(2, 1));
pSouth.add(pBtn, BorderLayout.SOUTH);
pSouth.add(pSCR, BorderLayout.CENTER);
// Table info
jT.setAutoResizeMode(jT.AUTO_RESIZE_OFF);
jT.setGridColor(Color.BLUE);
jT.setSelectionMode(ListSelectionModel.SINGLE_SELECTION);
jT.setSelectionBackground(Color.BLUE);
jT.setSelectionForeground(Color.WHITE);
jT.setRowSelectionAllowed(true);
/*
* Task 1. change action to diplay row = create the 2.delete row
* 3.insert row
*/
frame.setJMenuBar(jMenuBar);
frame.add(pdp, BorderLayout.NORTH);
frame.add(pSouth, BorderLayout.SOUTH);
frame.setTitle("Walters SPJ Directory");
frame.setResizable(true);
frame.setSize(465, 648);
frame.setLocationRelativeTo(null);
frame.setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
frame.setVisible(true);
// display rows
displayRow.addActionListener(new ActionListener() {
public void actionPerformed(ActionEvent e) {
// when the search button is clicked
if (e.getSource() == displayRow) {
jcmb.setSelectedItem(giveMeTableName);
for (int i = 0; i < jcmb.getSelectedIndex(); i++)
displayS();
}
}
});
// Checkbos ActionListener
rowS.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
jT.setRowSelectionAllowed(rowS.isSelected());
}
});
colS.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
jT.setRowSelectionAllowed(colS.isSelected());
}
});
// Clear ActionListener
clear.addActionListener(new ActionListener() {
@Override
public void actionPerformed(ActionEvent e) {
// TODO Auto-generated method stub
TableModel myData = DbUtils.resultSetToTableModel(rseTo);
jT.tableChanged(null);
}
});
}
// get tableNames
public void getTableNames() throws SQLException {
rseTo = null;
java.sql.DatabaseMetaData meta = DBCon.con.getMetaData();
rseTo = meta.getTables(null, null, "%", new String[] { "TABLE" });
while (rseTo.next()) {
String nameOfTables = rseTo.getString(3);
String tableCatalog = rseTo.getString(1);
String tableSchema = rseTo.getString(2);
System.out.printf("%s - %s - %s%n", tableCatalog, tableSchema,
nameOfTables);
}
db.stm.close();
}
// get table name to JCombobox
public void arrayOfTable() throws SQLException {
rseTo = db.con.getMetaData().getTables(null, null, "%",
new String[] { "TABLE" });
while (rseTo.next()) {
String giveMeTableName = (rseTo.getString(3));
jcmb.addItem(giveMeTableName);
System.out.println(giveMeTableName);
}
jcmb.setBounds(130, 30, 190, 30);
jcmb.setEditable(false);
jcmb.getSelectedIndex();
return;
}
/*
* Table selection method
*/
public void displayS() {
try {
String sql = "SELECT DISTINCT * FROM " + giveMeTableName;
pst = DBCon.con.prepareStatement(sql);
rseTo = pst.executeQuery();
TableModel myData = DbUtils.resultSetToTableModel(rseTo);
jT.setModel(myData);
} catch (Exception ex) {
JOptionPane.showMessageDialog(null, ex);
}
}
public void displayP() {
try {
String sql = "SELECT DISTINCT * FROM P";
pst = DBCon.con.prepareStatement(sql);
rseTo = pst.executeQuery();
jT.setModel(DbUtils.resultSetToTableModel(rseTo));
} catch (Exception ex) {
JOptionPane.showMessageDialog(null, ex);
}
}
public void displayJ() {
try {
String sql = "SELECT DISTINCT * FROM " + make.tableName;
pst = DBCon.con.prepareStatement(sql);
rseTo = pst.executeQuery();
jT.setModel(DbUtils.resultSetToTableModel(rseTo));
} catch (Exception ex) {
JOptionPane.showMessageDialog(null, ex);
}
}
public void displaySPJ() {
try {
String sql = "SELECT DISTINCT * FROM SPJ";
pst = DBCon.con.prepareStatement(sql);
rseTo = pst.executeQuery();
jT.setModel(DbUtils.resultSetToTableModel(rseTo));
} catch (Exception ex) {
JOptionPane.showMessageDialog(null, ex);
}
}
}