我想用DB中新添加或修改的信息刷新JTable
目前，当我点击showDetails或在数据库中插入1条记录后，它只能运行一次。
每次添加或删除新条目时，它都不会一次又一次地显示信息
代码属于GUIClass
package studentmanagementsystem.gui;
import javax.swing.*;
import java.awt.*;
import java.awt.event.*;
import java.sql.*;
import java.util.Vector;
import studentmanagementsystem.entity.*;
import studentmanagementsystem.backend.*;
public class StudentPersonalGui extends JFrame implements ActionListener{
JLabel heading,lenroll,lDOB,lgender,lmobileno,lemailid,lfathername,lname;
JLabel lmothername,laddress;
JTextField tenroll,tDOB,tmobileno,temailid,tfathername,tname;
JTextField tmothername,taddress;
JComboBox<String> cgender;
JButton insert,retrieve;
JButton reset;
JPanel p1,dataPanel;
String gender[]={"Male","Female"};
Font f1=new Font("BOLD",Font.ITALIC,25);
Color c1=Color.white;
Color c2=Color.lightGray ;
Color c3=new Color(50,100,10);
boolean insert_status;
StudentPersonal sp;
public StudentPersonalGui(){
setLayout(null);
heading=new JLabel("Student Personal Record");
heading.setFont(f1);
heading.setForeground(c3);
p1=new JPanel();
p1.add(heading);
p1.setBackground(c2);
p1.setLayout(null);
p1.setBounds(200,20,400,60);
heading.setBounds(50,10,300,30);
add(p1);
lenroll=new JLabel("Enrollment No.:");
lname=new JLabel("Student Name:");
lDOB=new JLabel("Date of Birth:");
lmobileno=new JLabel("Mobile No.:");
lemailid=new JLabel("Email Id:");
lgender=new JLabel("Gender:");
lfathername=new JLabel("Father Name:");
lmothername=new JLabel("Mother Name:");
laddress=new JLabel("Address:");
tenroll=new JTextField(12);
tname=new JTextField(12);
tDOB=new JTextField(12);
tmobileno=new JTextField(12);
temailid=new JTextField(12);
tfathername=new JTextField(12);
tmothername=new JTextField(12);
taddress=new JTextField(12);
cgender=new JComboBox<String>(gender);
insert=new JButton("Add Record");
retrieve=new JButton("View Details");
reset=new JButton("Reset");
add(lenroll);
add(lDOB);
add(lmobileno);
add(lgender);
add(lemailid);
add(lfathername);
add(lmothername);
add(lname);
add(laddress);
add(tenroll);
add(tDOB);
add(tmobileno);
add(cgender);
add(temailid);
add(tfathername);
add(tmothername);
add(tname);
add(taddress);
add(insert);
add(retrieve);
add(reset);
lenroll.setBounds(100,100,100,20);
tenroll.setBounds(220,100,150,20);
lname.setBounds(450,100,100,20);
tname.setBounds(570,100,200,20);
lDOB.setBounds(100,130,100,20);
tDOB.setBounds(220,130,120,20);
lgender.setBounds(450,130,100,20);
cgender.setBounds(570,130,100,20);
lmobileno.setBounds(100,160,100,20);
tmobileno.setBounds(220,160,120,20);
lemailid.setBounds(450,160,200,20);
temailid.setBounds(550,160,200,20);
lfathername.setBounds(100,190,100,20);
tfathername.setBounds(220,190,200,20);
lmothername.setBounds(100,220,100,20);
tmothername.setBounds(220,220,200,20);
laddress.setBounds(100,250,200,20);
taddress.setBounds(220,250,350,20);
insert.setBounds(150,300,150,20);
reset.setBounds(350,300,80,20);
retrieve.setBounds(480,300,150,20);
insert.addActionListener(this);
reset.addActionListener(this);
retrieve.addActionListener(this);
dataPanel=new JPanel();
dataPanel.setBounds(50,350,730,250);
dataPanel.setLayout(new BorderLayout());
dataPanel.setBackground(Color.WHITE);
add(dataPanel);
setResizable(false);
setVisible(true);
setSize(850,700);
setTitle("Student Record Management");
setDefaultCloseOperation(JFrame.EXIT_ON_CLOSE);
}
public void actionPerformed(ActionEvent ae){
if(ae.getActionCommand()=="Add Record"){
sp=new StudentPersonal();
String sDOB=tDOB.getText();
String sname=tname.getText();
String gender=(String)cgender.getSelectedItem();
String emailid=temailid.getText();
String fathername=tfathername.getText();
String mothername=tmothername.getText();
String address=taddress.getText();
long enrollno=0;
long mobileno=0;
try{
enrollno=Long.parseLong(tenroll.getText());
mobileno=Long.parseLong(tmobileno.getText());
}catch(NumberFormatException nfe){
JOptionPane.showMessageDialog(null,"Alphabets cann't be inserted in phone field","Information", JOptionPane.ERROR_MESSAGE);
}
sp.setSenrollno(enrollno);
sp.setSname(sname);
sp.setSDOB(sDOB);
sp.setSgender(gender);
sp.setSmobileno(mobileno);
sp.setSemailid(emailid);
sp.setSfathername(fathername);
sp.setSmothername(mothername);
sp.setSaddress(address);
insert_status=new CRUDOperations().insert(sp);
if(insert_status){
JOptionPane.showMessageDialog(null,"Record Inserted Successfully","Information", JOptionPane.INFORMATION_MESSAGE);
showData();
}
}
else if(ae.getActionCommand()=="View Details"){
showData();
}
else{
tenroll.setText("");
tDOB.setText("");
tmobileno.setText("");
temailid.setText("");
tfathername.setText("");
tname.setText("");
tmothername.setText("");
taddress.setText("");
cgender.setSelectedIndex(0);
}
}
public void showData(){
JTable table;
JScrollPane pane;
Vector<String> columnname=new Vector<String>();
Vector<Vector<String>> rowData=new Vector<Vector<String>>();
Vector<String> student;
try{
ResultSet rs=new CRUDOperations().retrieve_Data();
if(rs!=null){
ResultSetMetaData rsmd=rs.getMetaData();
int columnCount=rsmd.getColumnCount();
for(int j=1;j<=columnCount;j++){
columnname.add(rsmd.getColumnName(j));
}
while(rs.next()){
student=new Vector<String>();
student.add(rs.getString(1));
student.add(rs.getString(2));
student.add(rs.getString(3));
student.add(rs.getString(4));
student.add(rs.getString(5));
student.add(rs.getString(6));
student.add(rs.getString(7));
student.add(rs.getString(8));
student.add(rs.getString(9));
rowData.add(student);
}
rs.close();
table = new JTable(rowData,columnname);
pane=new JScrollPane(table);
dataPanel.add(pane,BorderLayout.CENTER);
add(dataPanel);
validate();
repaint();
}
}catch(SQLException sqle){
}
}
}
CRUDOperation Class 用于ShowDetails按钮上的DB Operation单击一个CRUDOperation函数调用retrieve_Data，它返回用于设置JTable数据的resultSet
package studentmanagementsystem.backend;
import java.awt.Color;
import java.sql.*;
import java.util.Vector;
import studentmanagementsystem.entity.*;
import studentmanagementsystem.gui.*;
public class CRUDOperations{
Connection con;
PreparedStatement stat;
StudentPersonal sp;
boolean insert_status,delete_status,update_status,login_status;
public boolean insert(StudentPersonal sp){
con=new ConnectionManager().makeConn();
try{
long enrollno=sp.getSenrollno();
String sname=sp.getSname();
String sDOB=sp.getSDOB();
String gender=sp.getSgender();
String emailid=sp.getSemailid();
long mobileno=sp.getSmobileno();
String fathername=sp.getSfathername();
String mothername=sp.getSmothername();
String address=sp.getSaddress();
String insertSP="insert into StudentPersonal values(?,?,?,?,?,?,?,?,?)";
stat=con.prepareStatement(insertSP);
stat.setLong(1,enrollno);
stat.setString(2,sname);
stat.setString(3,sDOB);
stat.setString(4,gender);
stat.setLong(5,mobileno);
stat.setString(6,emailid);
stat.setString(7,fathername);
stat.setString(8,mothername);
stat.setString(9,address);
int i=stat.executeUpdate();
if(i>0){
insert_status=true;
}
}catch(Exception e){
}
return insert_status;
}
public ResultSet retrieve_Data(){
ResultSet rs=null;
try{
con=new ConnectionManager().makeConn();
String retrieve="select * from StudentPersonal";
stat=con.prepareStatement(retrieve);
rs=stat.executeQuery();
}catch(SQLException sql){
System.out.println(sql);
}
return rs;
}
}
答案 0 :(得分：2)
您可以使用 TableModel 并更新内容，而不是为每个事件添加新的JTable。
的示例您可以在此处找到JDBC with JTable
的其他链接答案 1 :(得分：1)
在表模型中，您应该触发相应的事件，包括表行已更改，表列已更改，表数据更新等。
答案 2 :(得分：1)
对您的表使用DefaultTableModel，而不是直接将数据添加到表中。只需将数据添加到模型中并将此模型设置为您的表格。
DefaultTableModel dtm = new DefaultTableModel(data, columnNames);
JTable table = new JTable();
table.setModel(dtm);
现在，当您想要添加数据时，只需添加到您的模型中..
dtm.addRow(...);