querytea.java

一个毕业设计的Java学生成绩管理系统

package scoremis;
import java.awt.*;
import javax.swing.*;
import javax.swing.table.DefaultTableModel;   //
import java.until.Vector;     //
import java.sql.ResultSet;
import java.awt.event,*;
public class QueryTea extends JPanel
   {
     BorderLayout borderLayout1=new BorderLayout();//设置各种组件的初始值
     JLabel l1=new JLabel("值");
     JLabel jLabel1=new JLabel("查询条件");
     JComboBox tiaojian=new JCombobox();
     JTextField tname=new JTextField(10);
     JButton query=new JButton("查询");
     JButton scan=new JButton("浏览");
     JButton del=new JButton("删除");
     JButton edit=new JButton("修改")
     JTextField show=new JTextField(10);
     Vector tempvector=new Vector(1,1);
     DefaultTableModel model=new DefaultTableModel();//定义表格用于显示数据
     JTable dbtable=new JTable(model);
     JScrollPane sp=new JScrollPane(dbtable);//定义滑块并将滑块添加到表格当中
     ResultSet rs=null;   //定义数据集并分别定义字符串变量bh,zc,xb,xm用来存放"编号","职称","性别","姓名"
     String bh="";
     String zc="";
     String xb="";
     String xm="";
   public Querytea()
       {
         try
          {
            jbInit();
          }
         catch(Exception exception)
          {exception.printStackTrace();}
       } 
   private void jbInit() throws Exception  //添加各种组件
       {
       add(jLabel1);
       add(tiaojian);
       tiaojian.addItem("");   //在条件组合框中添加各个选项
       tiaojian.addItem("编号");
       tiaojian.addItem("姓名");
       tiaojian.addItem("性别");
       tiaojian.addItem("职称");
       add(l1);
       add(tname);
       add(query);
       add(scan);
       add(edit);
       add(del);
       add(sp,"Center");
       add(show,"North");
       query.addActionListener(new EventHandel());//分别为按钮"查询","浏览","删除","修改"按钮添加监视器
       scan.addActionListener(new EventHandel());
       edit.addActionListener(new EventHandel());
       del.addActionListener(new EventHandel());
       edit.setEnabled(false);   //设修改删除按钮的初始值为不可使用状态
       del.setEnabled(false);
       model.addColumn("编号");  //设表格的各列的名称分别为："编号","姓名","性别","职称"
       model.addColumn("姓名");
       model.addColumn("性别");
       model.addColumn("职称");
    dbtable.addMouseListener(new MouseAdapter())   //监视表格
       public void mouseClicked(MouseEvent e)
           {  //给表格添加监视器，当鼠标点击某条记录时，进行修改和删除
             int j=dbtable.getSelectedrow();  //利用整型变量j记录表格中的行数
             bh=(String) model.getValueAt(j,0);//用字符串变量bh,xm,xb,zc分别记录下第j行第i列的值
             xm=(String) model.getValueAt(j,1);
             xb=(String) model.getValueAt(j,2);
             zc=(String) model.getVauleAt(j,3);
             edit.setEnabled(true);
             del.setEnabled(true);
           }
       }     

   }
class EventHadel implements ActionListener  //事件处理类
 {
   public void actionPerformed(ActionEvent e)
      {
        dbconn db=new dbconn();
        String sql="";
        if(e.getSource()==scan || e.getSource==query)//用于处理"浏览","查询"的事件
          {
            int j=model.getRowCount();
            if(j>0)
               {
                 for(int i=0;i<j;i++)
                     model.removeRow(0);
               }
            if(e.getSource()==query)  //如果查询按钮获得焦点的事件处理
               {
                  String tj=(String)tiaojian.getSelectedItem();
                  String mingcheng="";
                  if(tj.equals("编号"))
                    mingcheng="ID";
                  if(tj.equals("姓名")) 
                     mingcheng="name";
                  if(tj.equals("性别"))
                     mingcheng="sex";
                  else 
                     mingcheng="title";
                  sql="select * from teacher where " + mingcheng + "='" tname.getText() "'";
                }
            else if(e.getSource()==scan)   //浏览按钮获得焦点的事件处理
                  sql="select * from teacher";
                try 
                  {
                     rs=db.Query(sql);   //执行查询操作
                        int i=0;
                        while(rs.next())
                            {
                              i++;
                              String tbh=rs.getString(1);
                              if(!tbh.startsWith("admin"))
                                {
                                  tempvector=new Vector(1.1);
                                  tempvector.add(tbh);
                                  tempvector.add(rs.getString(2));
                                  tempvector.add(rs.getString(4));
                                  tempvector.add(rs.getString(5));
                                  model.addRow(tempvector);   //将查询结果添加到表格中
                                }
                     
                            }
                         if(i==0)
                             JOptionPane.showMessageDialog(null,"数据库中尚未录入教师");
                             dbtable.setRowSelectionAllowed(true);
                             int rs=dbtable.getSelectedRow();
                  }
               catch(Exception e2)
                 {
                   System.out.println(e2.toString());
                 }
          }
           else if(e.getSource()==edit)  //修改按钮获得焦点的事件处理
                {
                   Toolkit tk=Toolkit.getDefaultToolkit();
                   Dimension sSize=tk.getScreenSize();  //
                   int  sh=sSize.height;
                   int sw=sSize.width;
                   editTea er=new editTea(bh,xm,xb,zc);  //调用类editTea的构造函数
                   JFrame editframe=new JFrame();
                   editframe.add(er);
                   editframe.setSize(sh/2,sh/2);
                   editframe.setLocation(sh/4,sh/4);
                   editframe.setVisible(true);
                }
           else if(e.getSource()==del)  //删除按钮获得焦点的事件处理
                {
                  try
                    {
                      dbtable.setVisible(false);
                      int e1=JOptionPane.showConfirmDialog(null,"确定要删除吗","确认",JOption Pane.OK_CANCEL_OPTION);
                      if(e1==0)
                      {
                        String sql2="";
                        String sql3="";
                        if(!tname.getText().equals(""))
                          {
                            sql="select ID from teacher where name='"+ tname.getText() +"'";
                            Resultset rs=db.Query(sql);
                            if(rs.next())
                              bh=rs.getString(1);
                          }
                         sql="delete * from teacher where ID='"+ bh +"'"; //从teacher表中删除相应的记录
                         sql2="select * from T_C where tID='"+ bh +"'";  //从tc:教师任课表中查询符合条件的记录并删除
                         sql3="delete * from T_C where tID='"+ bh +"'";
                         int i=db.Update(sql);     //执行删除操作
                         if(i>0)            // 根据执行sql语句的结果弹出相应的信息提示框
                            {
                               ResultSet rs=db.Query(sql2);
                               boolean hava=false;
                               if(rs.next())
                                 have=true ;
                               if(have==true) 
                                 {
                                   int j=db.Update(sql3);
                                   if(j>0)
                                     JOptionPane.showMessageDialog(null,"删除成功");
                                 }
                               else 
                                   {
                                     JOptionPane.showMessageDialog(null,"删除成功");
                                   }
                             
                            }
                      }
                    }catch(Exception er){}
                }
      }
 }