我想根据我使用AbstractTableModel指定的列从数据库中的表中提取数据。表中有8列，但只想显示8列中的3列。
例如：
数据库包含以下列：ID，First_Name，Last_Name，....，Phone_Number。如果我指定要在表中显示First_Name，Last_Name，Phone_Number，则会显示ID，First_Name和Last_Name。我想我应该从数据库中指定列名的索引以显示正确的列，但不知道如何在我的自定义AbstractTableModel类中实现它。
public class PhysicianModelController extends AbstractTableModel
{
PhysicianBroker pb = PhysicianBroker.getPhysicianBroker();
private String[] columnNames = {"First Name", "Last Name", "Phone Number"};
private ArrayList<Physician> ph = pb.getAllPhysicians();
@Override
public int getRowCount() {
return ph.size();
}
@Override
public int getColumnCount() {
return columnNames.length;
}
@Override
public String getColumnName(int col)
{
System.out.println(col);
return columnNames[col];
}
@Override
public String getValueAt(int rowIndex, int columnIndex) {
System.out.println(rowIndex + " : " + columnIndex);
Physician p = ph.get(rowIndex);
switch (columnIndex)
{
case 0:
return Integer.toString(p.getEmployeeId());
case 1:
return p.getFirstName();
case 2:
return p.getLastName();
case 3:
return p.getBirthDate();
case 4:
return p.getStartDate();
case 5:
return p.getEndDate();
case 6:
return p.getAddress();
case 7:
return p.getPhoneNumber();
default:
return "Incorrect input";
}
}
public void addRow(Physician p)
{
ph.add(p);
int row = ph.size();
fireTableRowsInserted(row,row);
fireTableDataChanged();
}
@Override
public Class getColumnClass(int c)
{
return getValueAt(0,c).getClass();
}
}
我已经用我的实现覆盖了getRowCount（），getColumnCount（），getColumnName（），getValueAt（）和getColumnClass（）方法。一旦我提供了数据库表中的所有列，一切都能正常工作。
有人愿意帮我解释如何做到这一点吗？
由于
答案 0 :(得分：1)
观看您的getValueAt方法。你只有三列。所以你应该根据它返回值。发生了什么，对于第0列，您获得了员工ID，而您想要Firstname..So on ...
@Override
public String getValueAt(int rowIndex, int columnIndex) {
System.out.println(rowIndex + " : " + columnIndex);
Physician p = ph.get(rowIndex);
switch (columnIndex)
{
case 0:
return p.getFirstName();
case 1:
return p.getLastName();
case 2:
return p.getPhoneNumber();
default:
return "Incorrect input";
}
}
<强>更新
这是一个在JTable中添加行的代码演示。看看它：
import javax.swing.*;
import javax.swing.border.*;
import java.awt.*;
import java.awt.event.*;
import javax.swing.table.*;
import java.util.*;
class Person
{
String name;
String roll;
String subject;
public Person(String name,String roll,String subject)
{
this.name = name;
this.roll = roll;
this.subject = subject;
}
public String getName()
{
return name;
}
public String getRoll()
{
return roll;
}
public String getSubject()
{
return subject;
}
public void setName(String name)
{
this.name = name;
}
public void setRoll(String roll)
{
this.roll = roll;
}
public void setSubject(String subject)
{
this.subject = subject;
}
}
class TableRowAdd extends JFrame
{
private JTable table;
private JScrollPane jsPane;
private MyModel myModel;
private JPanel dialogPanel;
private JTextField tf[];
private JLabel lbl[];
private JButton button;
JDialog dialog;
public void prepareAndShowGUI()
{
myModel = new MyModel();
table = new JTable(myModel);
jsPane = new JScrollPane(table);
button = new JButton("Add");
button.addActionListener(new ActionListener()
{
public void actionPerformed(ActionEvent evt)
{
dialog.setVisible(true);
}
});
getContentPane().add(button,BorderLayout.SOUTH);
getContentPane().add(jsPane);
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
prepareDialogPanel();
pack();
setVisible(true);
}
private void prepareDialogPanel()
{
dialogPanel = new JPanel();
int col = table.getColumnCount();
dialogPanel.setLayout(new GridLayout(col,2));
tf = new JTextField[col];
lbl = new JLabel[col];
for (int i = 0; i < col; i++)
{
lbl[i] = new JLabel(table.getColumnName(i));
tf[i] = new JTextField(10);
dialogPanel.add(lbl[i]);
dialogPanel.add(tf[i]);
}
dialog = new JDialog(this,"Enter details",true);
dialog.getContentPane().add(dialogPanel);
JButton okButton = new JButton("OK");
dialog.getContentPane().add(okButton,BorderLayout.SOUTH);
okButton.addActionListener( new ActionListener()
{
public void actionPerformed(ActionEvent evt)
{
dialog.dispose();
myModel.addRow(new Person(tf[0].getText(),tf[1].getText(),tf[2].getText()));
}
});
dialog.pack();
}
private class MyModel extends AbstractTableModel
{
String[] columns = {
"Roll No.",
"Name",
"Subject"
};
ArrayList<Person> inData = new ArrayList<Person>()
{
{
add(new Person("1","Anthony Hopkins","CS01"));
add(new Person("2","James William","CS02"));
add(new Person("3","Mc. Donald","CS03"));
}
};
@Override
public void setValueAt(Object value, int row, int col)
{
Person person = inData.get(row);
switch(col)
{
case 0:
person.setRoll((String)value);
break;
case 1:
person.setName((String)value);
break;
case 2:
person.setSubject((String)value);
break;
default:
System.out.println("Invalid col");
}
fireTableCellUpdated(row,col);
}
@Override
public Object getValueAt(int row, int col)
{
Person person = inData.get(row);
switch(col)
{
case 0:
return person.getRoll();
case 1:
return person.getName();
case 2:
return person.getSubject();
default:
return null;
}
}
@Override
public int getColumnCount()
{
return columns.length;
}
@Override
public int getRowCount()
{
return inData.size();
}
@Override
public String getColumnName(int col)
{
return columns[col];
}
@Override
public boolean isCellEditable(int row ,int col)
{
return true;
}
//This method adds a row to the table
public void addRow(Person person)
{
inData.add(person);
fireTableRowsInserted(inData.size() - 1 ,inData.size() - 1);
}
}
public static void main(String st[])
{
SwingUtilities.invokeLater( new Runnable()
{
@Override
public void run()
{
TableRowAdd td = new TableRowAdd();
td.prepareAndShowGUI();
}
});
}
}