zoukankan html css js c++ java

软件工程概论——引言课后作业，包括了解开发技术、学习计划，课堂测试内容

一、Java web开发

一下的划分并非按技术进行分类，只是个人的一种认识

1.动态网页技术：静态网页技术HTML的基本知识，servlet、JavaBean、jsp等Java语言层次上的知识以及美化网页的css和增加动态功能的javascript必备的知识

2.开发工具:数据库(包括JDBC技术)、web服务器(如tomcat)、集成的开发环境(myeclipse或eclipse)

二、本次课堂测试源代码:一个连接了SQL Server数据库的登录界面的实现

由于题目是提前公布的，于是我课下多做了些工作，这个题目我用两种方式实现的:

1.Java swing中自带的框架和组件来构建界面，由于这个方面我比较熟悉，所以我就多写了一个注册界面和登陆成功后的用户个人界面，不过时间有限，写的比较随意简陋:

数据结构:Student类

 1 public class Student {
 2       private String name;    //姓名
 3       private String pass;     //密码
 4       private String id;         //学号
 5       private String sex;       //性别
 6       private double score;    //分数
 7       private int age;
 8       public Student() {
 9           
10       }
11     public String getName() {
12         return name;
13     }
14     public void setName(String name) {
15         this.name = name;
16     }
17     public String getId() {
18         return id;
19     }
20     public void setId(String id) {
21         this.id = id;
22     }
23     public String getSex() {
24         return sex;
25     }
26     public void setSex(String sex) {
27         this.sex = sex;
28     }
29     public double getScore() {
30         return score;
31     }
32     public void setScore(double score) {
33         this.score = score;
34     }
35     public int getAge() {
36         return age;
37     }
38     public void setAge(int age) {
39         this.age = age;
40     }
41     public String getPass() {
42         return pass;
43     }
44     public void setPass(String pass) {
45         this.pass = pass;
46     }
47 }

工具类:全部为静态成员，包括连接数据库、添加、查找数据库中的成员

  1 package User;
  2 
  3 import java.sql.*;
  4 
  5 public class ConUtil {
  6       public static void InitSQL() {
  7           try {
  8               Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
  9              
 10           }catch(ClassNotFoundException | InstantiationException | IllegalAccessException e) {
 11               System.out.println(e.getMessage());
 12           }
 13           String user = "sa";                //默认就是这个
 14           String password = "******"; //这里输入你密码即可
 15           String url = "jdbc:sqlserver://localhost:1433;DasebaseName=master";
 16          //我使用的表是系统数据库master中我自己新建的表Student_Manage
 17           Connection connection = null;
 18           try {
 19               connection = DriverManager.getConnection(url,user,password);
 20           }catch(SQLException e) {
 21               System.out.println(e.getMessage());
 22           }
 23           ResultSet rs = null;
 24           Statement stmt = null;
 25           try {
 26               stmt = connection.createStatement();
 27             rs = connection.getMetaData().getTables(null,null,"Student_Message",null);
 28             if(!rs.next()) {   //如果数据表不存在则新建
 29                 String query = "create table Student_Message(id varchar(50),pass varchar(50),name nvarchar(50),sex nvarchar(50),score float,age int)";
 30                 stmt.executeQuery(query);
 31             }
 32             rs.close();
 33             stmt.close();
 34             connection.close();
 35         } catch (SQLException e) {
 36             // TODO 自动生成的 catch 块
 37             e.printStackTrace();
 38             System.out.println(e.getMessage());
 39         }
 40       }
 41       public static Connection getConnection() {
 42           try {
 43               Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
 44              
 45           }catch(ClassNotFoundException | InstantiationException | IllegalAccessException e) {
 46               System.out.println(e.getMessage());
 47           }
 48           String user = "sa";
 49           String password = "leomessi10";
 50           String url = "jdbc:sqlserver://localhost:1433;DasebaseName=master";
 51           Connection connection = null;
 52           try {
 53               connection = DriverManager.getConnection(url,user,password);
 54           }catch(SQLException e) {
 55               System.out.println(e.getMessage());
 56           }
 57           return connection;
 58       }
 59       
 60       
 61       public static int add(Student stu) {  //注册时使用
 62           Connection con = getConnection();
 63           String sql = "select * from Student_Message";
 64           PreparedStatement stmt = null;
 65             ResultSet rs = null;
 66             int flag = 1;
 67             try {   //先检查学号信息是否重复
 68               stmt = con.prepareStatement(sql);
 69             rs = stmt.executeQuery();
 70             
 71             while(rs.next()) {
 72                 if(rs.getString("id").equals(stu.getId())) {
 73                     flag = 0;
 74                     break;
 75                 }
 76             }
 77             if(flag==1) {
 78                 stmt = con.prepareStatement("insert into Student_Message values(?, ?, ?, ?, ?, ?)");
 79                 stmt.setString(1,stu.getId());
 80                 stmt.setString(2,stu.getPass());
 81                 stmt.setString(3,stu.getName());
 82                 stmt.setString(4,stu.getSex());
 83                 stmt.setDouble(5,stu.getScore());
 84                 stmt.setInt(6,stu.getAge());
 85                 stmt.executeUpdate();
 86             }
 87             rs.close();
 88             stmt.close();
 89             con.close();
 90         } catch (SQLException e) {
 91             // TODO 自动生成的 catch 块
 92             e.printStackTrace();
 93             System.out.println(e.getMessage());
 94         }
 95         if(flag==1)return 1;
 96         else return 0;
 97       }
 98       
 99       public static Student search(String id,String pass){
100           //登陆时使用，查找成功则返回对应的Student类对象
101           Connection con = getConnection();
102           String sql = "select * from Student_Message";
103           PreparedStatement stmt = null;
104             ResultSet rs = null;
105             Student stu = null;
106             try {
107               stmt = con.prepareStatement(sql);
108             rs = stmt.executeQuery();
109             
110             while(rs.next()) {
111                 if(rs.getString("id").equals(id)&&rs.getString("pass").equals(pass)) {
112                     stu = new Student();
113                     stu.setId(id);
114                     stu.setAge(rs.getInt("age"));
115                     stu.setName(rs.getString("name"));
116                     stu.setPass(pass);
117                     stu.setScore(rs.getDouble("score"));
118                     stu.setSex(rs.getString("sex"));
119                     break;
120                 }
121             }
122             rs.close();
123             stmt.close();
124             con.close();
125         } catch (SQLException e) {
126             // TODO 自动生成的 catch 块
127             System.out.println(e.getMessage());
128         }
129         return stu;
130       }
131       public static void update(String id,String pass,String age) {
132           //修改学生信息,仅限于修改年龄和登陆密码
133           Connection con = getConnection();
134           String sql = "update Student_Message set pass = ? , age = ? where id = ?";
135           PreparedStatement stmt = null;
136             try {
137               stmt = con.prepareStatement(sql);
138             stmt.setString(1,pass);
139             stmt.setInt(2,Integer.valueOf(age));
140             stmt.setString(3,id);
141             stmt.executeUpdate();
142             stmt.close();
143             con.close();
144         } catch (SQLException e) {
145             // TODO 自动生成的 catch 块
146             System.out.println(e.getMessage());
147         }
148       
149       }
150       
151 }

界面构建的代码:

  1 import javax.swing.*;
  2 import java.awt.CardLayout;
  3 import java.awt.Color;
  4 import java.awt.Font;
  5 import java.awt.Image;
  6 import java.awt.event.ActionEvent;
  7 import java.awt.event.ActionListener;
  8 
  9 public class Login extends JFrame{
 10       Student stu_option = null;
 11       CardLayout card = null;
 12       JPanel Main = null;
 13       JPanel panel1 = null;    //登陆界面
 14       JPanel panel2 = null;    //注册界面
 15       JPanel panel3 = null;    //用户界面
 16       public Login() {
 17           super("乞丐版管理系统");
 18           card = new CardLayout();
 19           Main = new JPanel();
 20           panel1 = new JPanel();
 21           panel2 = new JPanel();
 22           panel3 = new JPanel();
 23           Main.setSize(400,400);
 24           panel1.setSize(400,400);
 25           panel2.setSize(400,400);
 26           panel3.setSize(400,400);
 27           this.setLayout(null);
 28           this.add(Main);
 29           Main.setLayout(card);
 30           Main.add(panel1,"log");
 31           Main.add(panel2,"reg");
 32           Main.add(panel3,"qzone");
 33           
 34           
 35           //登录界面的初始化
 36           panel1.setLayout(null);
 37           JLabel log_id = new JLabel("学号");   
 38           log_id.setFont(new Font("微软雅黑",Font.BOLD,20));
 39           JLabel log_pass = new JLabel("密码");
 40           log_pass.setFont(new Font("微软雅黑",Font.BOLD,20));
 41           JTextField log1_id = new JTextField();
 42           log1_id.setFont(new Font("微软雅黑",Font.BOLD,20));
 43           JPasswordField log1_pass = new JPasswordField();
 44           JButton log_button = new JButton("登陆");
 45           log_button.setFont(new Font("微软雅黑",Font.BOLD,20));
 46           JButton reg_button = new JButton("注册");
 47           reg_button.setFont(new Font("微软雅黑",Font.BOLD,20));
 48           JLabel log_tip = new JLabel();
 49           log_tip.setFont(new Font("微软雅黑",Font.BOLD,20));
 50           
 51           log_id.setBounds(20,50,50,50);   //归置各组件的位置
 52           log1_id.setBounds(100,50,150,50);
 53           log_pass.setBounds(20,110,50,50);
 54           log1_pass.setBounds(100,110,150,50);
 55           log_tip.setBounds(50,170,300,50);
 56          
 57           log_button.setBounds(50,250,100,50);
 58           reg_button.setBounds(200,250,100,50);
 59           
 60           log_button.addActionListener(new ActionListener() {
 61             //为登陆按钮添加监听器
 62             @Override
 63             public void actionPerformed(ActionEvent e) {
 64                 // TODO 自动生成的方法存根
 65                 log_tip.setText("");
 66                 String id = log1_id.getText();
 67                 String pass = new String(log1_pass.getPassword());
 68                 if(id==null||pass==null||
 69                    id.equals("")||pass.equals("")) 
 70                     log_tip.setText("学号或密码不能为空");
 71                 else {
 72                     stu_option = ConUtil.search(id,pass);
 73                     if(stu_option!=null) {
 74                         log_tip.setText("");
 75                         log1_id.setText("");
 76                         log1_pass.setText("");
 77                         
 78                         card.show(Main,"qzone");
 79                     }
 80                     if(stu_option==null) {
 81                         log_tip.setForeground(Color.RED);
 82                         log_tip.setText("学号不存在或密码有误!");
 83                     }
 84                         
 85                 }
 86             }
 87               
 88           });
 89           
 90           reg_button.addActionListener(new ActionListener() {
 91               
 92             @Override
 93             public void actionPerformed(ActionEvent e) {
 94                 // TODO 自动生成的方法存根
 95                 log_tip.setText("");
 96                 log1_id.setText("");
 97                 log1_pass.setText("");
 98                 card.show(Main, "reg");
 99             }
100               
101           });
102           
103           panel1.add(log_id);        //添加各个组件
104           panel1.add(log_pass);
105           panel1.add(log1_pass);
106           panel1.add(log1_id);
107           panel1.add(log_tip);
108           panel1.add(log_button);
109           panel1.add(reg_button);
110           
111           
112           //注册界面的初始化
113           panel2.setLayout(null);
114           JLabel reg_id = new JLabel("学号");
115           reg_id.setFont(new Font("微软雅黑",Font.BOLD,20));
116           reg_id.setBounds(10,10,50,50);
117           JTextField reg1_id = new JTextField();
118           reg1_id.setFont(new Font("微软雅黑",Font.BOLD,20));
119           reg1_id.setBounds(60,10,150,50);
120           JLabel reg_pass = new JLabel("密码");
121           reg_pass.setBounds(10,60,50,50);
122           reg_pass.setFont(new Font("微软雅黑",Font.BOLD,20));
123           JTextField reg1_pass = new JTextField();
124           reg1_pass.setBounds(60,60,150,50);
125           JLabel reg_sex = new JLabel("性别");
126           reg_sex.setFont(new Font("微软雅黑",Font.BOLD,20));
127           reg_sex.setBounds(10,110,50,50);
128           JComboBox <String>sex1 = new JComboBox <String>();
129           sex1.addItem("男");
130           sex1.addItem("女");
131           sex1.setBounds(60,110,100,50);
132           JLabel reg_name = new JLabel("姓名");
133           reg_name.setFont(new Font("微软雅黑",Font.BOLD,20));
134           reg_name.setBounds(10,160,50,50);
135           JTextField reg1_name = new JTextField();
136           reg1_name.setFont(new Font("微软雅黑",Font.BOLD,20));
137           reg1_name.setBounds(60,160,150,50);
138           JLabel reg_mark = new JLabel("分数");
139           reg_mark.setFont(new Font("微软雅黑",Font.BOLD,20));
140           reg_mark.setBounds(10,210,50,50);
141           JTextField reg1_mark = new JTextField();
142           reg1_mark.setBounds(60,210,150,50);
143           JLabel reg_age= new JLabel("年龄");
144           reg_age.setFont(new Font("微软雅黑",Font.BOLD,20));
145           reg_age.setBounds(10,260,50,50);
146           JTextField reg1_age = new JTextField();
147           reg1_age.setBounds(60,260,150,50);
148           JButton reg = new JButton("确认注册");
149           reg.setFont(new Font("微软雅黑",Font.BOLD,20));
150           reg.setBounds(50,310,150,50);
151           reg.addActionListener(new ActionListener() {
152 
153             @Override
154             public void actionPerformed(ActionEvent e) {
155                 // TODO 自动生成的方法存根
156                 if(e.getActionCommand().equals("确认注册")) {
157                     String name = reg1_name.getText();
158                     String id = reg1_id.getText();
159                     String sex = (String)sex1.getSelectedItem();
160                     String pass = reg1_pass.getText();
161                     String mark = reg1_mark.getText();
162                     String age = reg1_age.getText();
163                     if(name==null||id==null||
164                        sex==null||pass==null||
165                        mark==null||age==null||
166                        name.equals("")||id.equals("")||
167                        sex.equals("")||pass.equals("")||
168                        mark.equals("")||age.equals(""))
169                         reg1_name.setText("不能为空!");
170                     else {
171                         double mark1 = Double.valueOf(mark);
172                         int age1 = Integer.valueOf(age);
173                         Student stu = new Student();
174                         stu.setAge(age1);
175                         stu.setId(id);
176                         stu.setName(name);
177                         stu.setSex(sex);
178                         stu.setPass(pass);
179                         stu.setScore(mark1);
180                         ConUtil.add(stu);
181                         reg.setText("返回登陆");
182                         
183                     }
184                     
185                 }
186                 else if(e.getActionCommand().equals("返回登陆")) {
187                     reg1_name.setText("");
188                     reg1_id.setText("");
189                     reg1_pass.setText("");
190                     reg1_mark.setText("");
191                     reg1_age.setText("");
192                     card.show(Main,"log");
193                 }
194             }
195               
196           });
197           
198           panel2.add(reg_id);
199           panel2.add(reg1_id);
200           panel2.add(reg_pass);
201           panel2.add(reg1_pass);
202           panel2.add(reg_sex);
203           panel2.add(sex1);
204           panel2.add(reg_name);
205           panel2.add(reg1_name);
206           panel2.add(reg_mark);
207           panel2.add(reg1_mark);
208           panel2.add(reg_age);
209           panel2.add(reg1_age);
210           panel2.add(reg);
211           
212           
213           //用户界面的设计
214          
215           panel3.setLayout(null);
216           JLabel title = new JLabel("学生空间");
217           title.setFont(new Font("微软雅黑",Font.BOLD,17));
218           title.setForeground(Color.RED);
219           title.setBounds(10,10,90,50);
220           JButton button_update = new JButton("修改信息");
221           button_update.setFont(new Font("微软雅黑",Font.BOLD,15));
222           button_update.setBounds(0,60,100,50);
223           JButton button_chart = new JButton("个人课表");
224           button_chart.setBounds(0,110,100,50);
225           button_chart.setFont(new Font("微软雅黑",Font.BOLD,15));
226           JButton button_mark = new JButton("个人成绩");
227           button_mark.setBounds(0,160,100,50);
228           button_mark.setFont(new Font("微软雅黑",Font.BOLD,15));
229           panel3.add(title);
230           panel3.add(button_update);
231           panel3.add(button_chart);
232           panel3.add(button_mark);
233           
234           
235           
236           //用户界面的分界面
237           JPanel userFrame = new JPanel();
238           CardLayout card1 = new CardLayout();
239           userFrame.setSize(300,400);
240           userFrame.setLayout(card1);
241           userFrame.setBounds(100,0,300,400);
242           panel3.add(userFrame);
243           JPanel[]user = new JPanel[3];
244           for(int i = 0;i<3;++i) {
245               user[i] = new JPanel();
246               user[i].setLayout(null);
247               user[i].setSize(300,400);
248           }
249           
250           userFrame.add(user[1],"chart");
251           userFrame.add(user[2],"mark");
252           userFrame.add(user[0],"update");
253           
254          
255           
256           
257           
258           //修改信息界面
259           JLabel update_title = new JLabel("修改信息");
260           update_title.setFont(new Font("微软雅黑",Font.BOLD,15));
261           update_title.setBounds(50,0,100,50);
262           JLabel update_age = new JLabel("年龄");
263           update_age.setFont(new Font("微软雅黑",Font.BOLD,15));
264           update_age.setBounds(10,50,50,50);
265           JTextField update_age1 = new JTextField();
266           update_age1.setFont(new Font("微软雅黑",Font.BOLD,15));
267           update_age1.setBounds(10,50,100,50);
268           JLabel update_pass = new JLabel("密码");
269           update_pass.setFont(new Font("微软雅黑",Font.BOLD,15));
270           update_pass.setBounds(10,100,50,50);
271           JTextField update_pass1 = new JTextField();
272           update_pass1.setFont(new Font("微软雅黑",Font.BOLD,15));
273           update_pass1.setBounds(10,150,100,50);
274           JButton update_button = new JButton("确认");
275           update_button.setFont(new Font("微软雅黑",Font.BOLD,15));
276           update_button.setBounds(100,200,100,50);
277           user[0].add(update_title);
278           user[0].add(update_pass);
279           user[0].add(update_pass1);
280           user[0].add(update_age1);
281           user[0].add(update_age);
282           user[0].add(update_pass);
283           user[0].add(update_pass1);
284           user[0].add(update_button);
285           update_button.addActionListener(new ActionListener() {
286               public void actionPerformed(ActionEvent e) {
287                   String pass = update_pass1.getText();
288                   String age = update_age1.getText();
289                   if(pass.equals("")||age.equals(""))
290                       update_pass1.setText("不能为空!");
291                   else {
292                       ConUtil.update(stu_option.getId(), pass, age);
293                   }
294               }
295           });
296           
297           //个人课表
298           JLabel tips = new JLabel("暂无服务");
299           tips.setFont(new Font("微软雅黑",Font.BOLD,20));
300           tips.setBounds(50,50,100,50);
301           JLabel image = new JLabel(new ImageIcon("logo.jpg"));
302           image.setBounds(80,150,100,100);
303           user[1].add(tips);
304           user[1].add(image);
305           
306           
307           //个人成绩
308           JLabel table = new JLabel("学号:姓名:成绩");
309           table.setBounds(10,10,200,100);
310           JLabel image1 = new JLabel(new ImageIcon("image1.jpg"));
311           JScrollPane jsp = new JScrollPane(image1,ScrollPaneConstants.VERTICAL_SCROLLBAR_AS_NEEDED,ScrollPaneConstants.HORIZONTAL_SCROLLBAR_AS_NEEDED);
312           jsp.setBounds(0,120,250,200);
313           user[2].add(table);
314           user[2].add(jsp); 
315           
316           button_update.addActionListener(new ActionListener() {
317               public void actionPerformed(ActionEvent e) {
318                   update_age1.setText(String.valueOf(stu_option.getAge()));
319                   System.out.println(stu_option.getAge());
320                   update_pass1.setText(stu_option.getPass());
321                   card1.show(userFrame,"update");
322               }
323           });
324           
325           button_chart.addActionListener(new ActionListener() {
326               public void actionPerformed(ActionEvent e) {
327                   card1.show(userFrame,"chart");
328               }
329           });
330           
331           button_mark.addActionListener(new ActionListener() {
332               public void actionPerformed(ActionEvent e) {
333                   table.setText("姓名:"+stu_option.getName()+" 综合成绩:"+stu_option.getScore());
334                   card1.show(userFrame,"mark");
335               }
336           });
337           
338           this.setVisible(true);
339           this.setResizable(false);
340           this.setDefaultCloseOperation(EXIT_ON_CLOSE);
341           this.setSize(400,400);
342       }
343       public static void main(String[]args) {
344           ConUtil.InitSQL();
345           SwingUtilities.invokeLater(new Runnable() {
346               public void run() {
347                   try {
348                       UIManager.setLookAndFeel(UIManager      //UIManager界面管理,可以改变当前界面的风格
349                               .getSystemLookAndFeelClassName());  //选择当前系统的界面风格
350                   } catch (Exception exception) {
351                       exception.printStackTrace();
352                   }
353                   new Login();
354               }
355           });
356           
357       }
358 }

放几张验证截图:

注册界面

登陆界面:

登陆成功后显示个人空间:

2.正经的用jsp那一套东西来写一个简单的登陆界面:

首先利用.Java文件完成基本操作,连接数据库、添加、查找数据库中的成员,还有一些异常情况

不过这次我没有把创建表的操作写在代码中，需要手动在SQL Server中建立

UserException.Java

 1 public class UserException extends RuntimeException{
 2     public UserException() {
 3           super();
 4     }
 5 
 6     public UserException(String arg0, Throwable arg1, boolean arg2, boolean arg3) {
 7         super(arg0, arg1, arg2, arg3);
 8         // TODO 自动生成的构造函数存根
 9     }
10 
11     public UserException(String arg0, Throwable arg1) {
12         super(arg0, arg1);
13         // TODO 自动生成的构造函数存根
14     }
15 
16     public UserException(String arg0) {
17         super(arg0);
18         // TODO 自动生成的构造函数存根
19     }
20 
21     public UserException(Throwable arg0) {
22         super(arg0);
23         // TODO 自动生成的构造函数存根
24     }
25       
26 }

User.Java

 1 public class User {
 2     private int id;
 3     private String username;
 4     private String password;
 5     private String nickname;
 6     public int getId() {
 7         return id;
 8     }
 9     public void setId(int id) {
10         this.id = id;
11     }
12     public String getUsername() {
13         return username;
14     }
15     public void setUsername(String username) {
16         this.username = username;
17     }
18     public String getPassword() {
19         return password;
20     }
21     public void setPassword(String password) {
22         this.password = password;
23     }
24     public String getNickname() {
25         return nickname;
26     }
27     public void setNickname(String nickname) {
28         this.nickname = nickname;
29     }
30 }

DBUtil.Java

 1 import java.sql.Connection;
 2 import java.sql.DriverManager;
 3 import java.sql.PreparedStatement;
 4 import java.sql.ResultSet;
 5 import java.sql.SQLException;
 6 
 7 public class DBUtil {
 8       public static Connection getConnection() {
 9           try {
10               Class.forName("com.microsoft.sqlserver.jdbc.SQLServerDriver").newInstance();
11              
12           }catch(ClassNotFoundException | InstantiationException | IllegalAccessException e) {
13               System.out.println(e.getMessage());
14           }
15           String user = "sa";      //和上面的例子一样，不过这次换了个表
16           String password = "******";
17           String url = "jdbc:sqlserver://localhost:1433;DasebaseName=master";
18           Connection connection = null;
19           try {
20               connection = DriverManager.getConnection(url,user,password);
21           }catch(SQLException e) {
22               System.out.println(e.getMessage());
23           }
24           return connection;
25       }
26       
27       public static void close(Connection connection) {
28          
29             try { 
30                 if(connection!=null)
31                      connection.close();
32             } catch (SQLException e) {
33                 // TODO 自动生成的 catch 块
34                 System.out.println(e.getMessage());
35             }
36       }
37       
38       public static void close(PreparedStatement preparedStatement) {
39           
40             try {
41                 if(preparedStatement!=null)
42                      preparedStatement.close();
43             } catch (SQLException e) {
44                 // TODO 自动生成的 catch 块
45                 System.out.println(e.getMessage());
46             }
47       }
48       
49       public static void close(ResultSet resultSet) {
50          
51             try { 
52                 if(resultSet!=null)
53                      resultSet.close();
54             } catch (SQLException e) {
55                 // TODO 自动生成的 catch 块
56                 System.out.println(e.getMessage());
57             }
58       }
59 }

UserDao.Java

  1 import java.sql.Connection;
  2 import java.sql.PreparedStatement;
  3 import java.sql.ResultSet;
  4 import java.sql.SQLException;
  5 import java.util.ArrayList;
  6 import java.util.List;
  7 
  8 import msg.Util.DBUtil;
  9 import msg.Util.UserException;
 10 import msg.Util.User;
 11 
 12 public class UserDao{
 13 
 14     
 15     public void add(User user) {
 16         Connection connection = DBUtil.getConnection();
 17         String sql = "select count(*) from t_user where username = ?";
 18         PreparedStatement preparedStatement = null;
 19         ResultSet resultSet = null;
 20         try {
 21             preparedStatement = connection.prepareStatement(sql);
 22             preparedStatement.setString(1,user.getUsername());
 23             resultSet = preparedStatement.executeQuery();
 24             while(resultSet.next()) {
 25                 if(resultSet.getInt(1)>0)throw new UserException("用户已存在");
 26             }
 27             sql = "insert into t_user(username,password,nickname) values(?,?,?)";
 28             preparedStatement = connection.prepareStatement(sql);
 29             preparedStatement.setString(1,user.getUsername());
 30             preparedStatement.setString(2,user.getPassword());
 31             preparedStatement.setString(3,user.getNickname());
 32             preparedStatement.executeUpdate();
 33         } catch (SQLException e) {
 34             // TODO 自动生成的 catch 块
 35             System.out.println(e.getMessage());
 36         }finally {
 37             DBUtil.close(resultSet);
 38             DBUtil.close(preparedStatement);
 39             DBUtil.close(connection);
 40         }
 41         
 42     }
 43  
 44      
 45     public void delete(int id) {
 46     
 47         Connection connection = DBUtil.getConnection();
 48         String sql = "delete from t_user where id = ?";
 49         PreparedStatement preparedStatement = null;
 50         try {
 51             preparedStatement = connection.prepareStatement(sql);
 52             preparedStatement.setInt(1, id);
 53             preparedStatement.executeUpdate();
 54         } catch (SQLException e) {
 55             // TODO 自动生成的 catch 块
 56             System.out.println(e.getMessage());
 57         }
 58         finally {
 59             DBUtil.close(preparedStatement);
 60             DBUtil.close(connection);
 61         }
 62     }
 63     
 64     
 65     public void delete(String username) {
 66         Connection connection = DBUtil.getConnection();
 67         String sql = "delete from t_user where username = ?";
 68         PreparedStatement preparedStatement = null;
 69         try {
 70             preparedStatement = connection.prepareStatement(sql);
 71             preparedStatement.setString(1, username);
 72             preparedStatement.executeUpdate();
 73         } catch (SQLException e) {
 74             // TODO 自动生成的 catch 块
 75             System.out.println(e.getMessage());
 76         }
 77         finally {
 78             DBUtil.close(preparedStatement);
 79             DBUtil.close(connection);
 80         }
 81     }
 82 
 83     
 84     public void update(User user) {
 85         
 86         Connection connection = DBUtil.getConnection();
 87         String sql = "update t_user set password = ? , nickname = ? where id = ?";
 88         PreparedStatement preparedStatement= null;
 89         
 90         try {
 91             preparedStatement= connection.prepareStatement(sql);
 92             preparedStatement.setString(1, user.getPassword());
 93             preparedStatement.setString(2, user.getNickname());
 94             preparedStatement.setInt(3, user.getId());
 95             preparedStatement.executeUpdate();
 96         } catch (SQLException e) {
 97             // TODO 自动生成的 catch 块
 98             System.out.println(e.getMessage());
 99         }finally {
100             DBUtil.close(preparedStatement);
101             DBUtil.close(connection);
102         }
103         
104     }
105 
106     
107     public User load(int id) {
108     
109         Connection connection = DBUtil.getConnection();
110         String sql = "select * from t_user where id = ?";
111         PreparedStatement preparedStatement = null;
112         User user = null;
113         ResultSet resultSet = null;
114         try {
115             preparedStatement = connection.prepareStatement(sql);
116             preparedStatement.setInt(1, id);
117             resultSet = preparedStatement.executeQuery();
118             while(resultSet.next()) {
119                 user = new User();
120                 user.setId(id);
121                 user.setUsername(resultSet.getString("username"));
122                 user.setPassword(resultSet.getString("password"));
123                 user.setNickname(resultSet.getString("nickname"));
124             }
125         } catch (SQLException e) {
126             // TODO 自动生成的 catch 块
127             System.out.println(e.getMessage());
128         }finally {
129             DBUtil.close(resultSet);
130             DBUtil.close(preparedStatement);
131             DBUtil.close(connection);
132         }
133         return user;
134     }
135 
136 
137     public User load(String username) {
138         Connection connection = DBUtil.getConnection();
139         String sql = "select * from t_user where username = ?";
140         PreparedStatement preparedStatement = null;
141         User user = null;
142         ResultSet resultSet = null;
143         try {
144             preparedStatement = connection.prepareStatement(sql);
145             preparedStatement.setString(1, username);
146             resultSet = preparedStatement.executeQuery();
147             while(resultSet.next()) {
148                 
149                 user = new User();
150                 user.setId(resultSet.getInt("id"));
151                 user.setUsername(resultSet.getString("username"));
152                 user.setPassword(resultSet.getString("password"));
153                 user.setNickname(resultSet.getString("nickname"));
154             }
155         } catch (SQLException e) {
156             // TODO 自动生成的 catch 块
157             System.out.println(e.getMessage());
158         }finally {
159             DBUtil.close(resultSet);
160             DBUtil.close(preparedStatement);
161             DBUtil.close(connection);
162         }
163         return user;
164     }
165     public List<User> load() {
166         Connection connection = DBUtil.getConnection();
167         String sql = "select * from t_user";
168         PreparedStatement preparedStatement = null;
169         ResultSet resultSet = null;
170         List<User> users = new ArrayList<User>();
171         User user = null;
172         try {
173             preparedStatement = connection.prepareStatement(sql);
174             resultSet = preparedStatement.executeQuery();
175             while(resultSet.next()) {
176                 user = new User();
177                 user.setId(resultSet.getInt("id"));
178                 user.setUsername(resultSet.getString("username"));
179                 user.setPassword(resultSet.getString("password"));
180                 user.setNickname(resultSet.getString("nickname"));
181                 users.add(user);
182             }
183         } catch (SQLException e) {
184             // TODO 自动生成的 catch 块
185             System.out.println(e.getMessage());
186         }finally {
187             DBUtil.close(resultSet);
188             DBUtil.close(preparedStatement);
189             DBUtil.close(connection);
190         }
191         return users;
192     }
193     
194 }

接下来就是jsp中的代码:

menu.jsp

 1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 2 <html>
 3 <head>
 4 <%@ page language="java" contentType="text/html; charset=UTF-8"
 5     pageEncoding="UTF-8"%>
 6 
 7 <title>菜单界面</title>
 8 </head>
 9 <body>
10 
11 <a href="addInput.jsp">用户注册界面</a><br>
12 <a href="loginInput.jsp">用户登陆界面</a><br>
13 
14 </body>
15 </html>

用户注册界面:addInput.jsp

 1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 2 <html>
 3 <head>
 4 <%@ page language="java" contentType="text/html; charset=UTF-8"
 5     pageEncoding="UTF-8"%>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>用户添加页面</title>
 8 </head>
 9 <body>
10   
11       <%
12             String tip = (String)request.getAttribute("error");
13             if(tip==null)tip = "";
14       %>
15      
16       <div align="center">用户添加界面</div>
17       <form action="add.jsp" method="get">
18            <table align="center" border="1" width="500">
19                <tr>
20                    <td>用户名称:</td>
21                    <td>
22                         <input type="text" name="username" />
23                    </td>
24                 </tr>
25                 <tr>
26                 <td>用户密码:</td>
27                 <td>
28                         <input type="password" name="password" />
29                 </td>
30                    </tr>
31                <tr>
32                 <td>用户昵称:</td>
33                 <td>
34                         <input type="text" name="nickname" />
35                 </td>
36                    </tr>  
37                    <tr align="center">
38                        <td colspan="2">
39                           <input type="submit" value="提交" />
40                           <input type="reset" value="重置" />
41                         </td>
42                     </tr>    
43            </table>
44        
45       </form>
46          <div align="center"><%=tip %></div>
47 </body>
48 </html>

后台处理注册请求:add.jsp

 1 <%@page import="msg.Util.User"%>
 2 <%@page import="msg.Util.UserException" %>
 3 <%@page import="msg.Util.UserDao" %>
 4 
 5 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 6 <html>
 7 
 8 <%@ page language="java" contentType="text/html; charset=UTF-8"
 9     pageEncoding="UTF-8"%>
10 <%
11     //接收客户端传递过来的参数
12     String username = request.getParameter("username");
13     String password = request.getParameter("password");
14     String nickname = request.getParameter("nickname");
15     
16     if(username==null||"".equals(username.trim())){
17         
18         request.setAttribute("error","用户名不能为空");
19     
20 %>
21     <jsp:forward page = "addInput.jsp"></jsp:forward>
22 <%
23     }
24     User user = new User();
25     user.setUsername(username);
26     user.setPassword(password);
27     user.setNickname(nickname);
28     
29     UserDao userDao = new UserDao();
30     try{
31     userDao.add(user);    
32     
33  %>
34 
35      用户保存成功!!<br>
36    <a href="menu.jsp">返回主界面</a><br> 
37 <%
38     }catch(UserException e){
39 %>        <h2 style="color:red;font-size:50px">发生错误<%=e.getMessage() %></h2>
40         <a href="addInput.jsp">返回用户添加界面</a><br>
41     <%
42     }
43     %>
44     
45 
46 
47 </html>

登录界面:login.jsp

 1 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 2 <html>
 3 <head>
 4 <%@ page language="java" contentType="text/html; charset=UTF-8"
 5     pageEncoding="UTF-8"%>
 6 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 7 <title>用户登陆</title>
 8 </head>
 9 <body>
10  <%
11             String tip = (String)request.getAttribute("error");
12             if(tip==null)tip = "";
13       %>
14      
15       <div align="center">用户登陆界面</div>
16       <form action="login.jsp" method="get">
17            <table align="center" border="1" width="500">
18                <tr>
19                    <td>用户名称:</td>
20                    <td>
21                         <input type="text" name="username" />
22                    </td>
23                 </tr>
24                 <tr>
25                 <td>用户密码:</td>
26                 <td>
27                         <input type="password" name="password" />
28                 </td>
29                    </tr>
30                    <tr align="center">
31                        <td colspan="2">
32                           <input type="submit" value="登陆" />
33                           <input type="reset" value="重置" />
34                         </td>
35                     </tr>    
36            </table>
37        
38       </form>
39          <div align="center"><%=tip %></div>
40 </body>
41 </html>

处理登陆界面:loginInput.jsp

 1 <%@page import="msg.Util.UserDao" %>
 2 <%@page import="msg.Util.User"%>
 3 <!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
 4 <html>
 5 <head>
 6 <%@ page language="java" contentType="text/html; charset=UTF-8"
 7     pageEncoding="UTF-8"%>
 8 <meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
 9 <title>用户登陆</title>
10 </head>
11 <body>
12     
13 <%
14     String username = request.getParameter("username");
15     String password = request.getParameter("password");
16     
17     if(username==null||"".equals(username.trim())){
18         request.setAttribute("error","用户名不能为空");
19 %>
20    <jsp:forward page = "loginInput.jsp"></jsp:forward>  
21 <%
22 }
23     if(password==null||"".equals(password)){
24          request.setAttribute("passerror","密码不能为空");
25     
26 %>
27     <jsp:forward page = "loginInput.jsp"></jsp:forward>  
28 <%
29     }
30     User user = null;
31     user = new UserDao().load(username);
32     if(user==null){   
33         request.setAttribute("error","该用户不存在");
34 %>
35     <jsp:forward page = "loginInput.jsp"></jsp:forward> 
36 <%
37     }   
38     else if(!user.getPassword().equals(password)){
39         request.setAttribute("error","密码错误");
40 %>
41     <jsp:forward page = "loginInput.jsp"></jsp:forward> 
42 <%
43     }
44     else{
45         request.setAttribute("login",user);
46 %>   
47     <jsp:forward page = "qzone.jsp"></jsp:forward> 
48     <%
49     }
50     %>
51 </body>
52 </html>

登录后用户个人空间:qzone.jsp

<%@page import="msg.Util.User"%>
<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN">
<html>
<head>
<%@ page language="java" contentType="text/html; charset=UTF-8"
    pageEncoding="UTF-8"%>
<meta http-equiv="Content-Type" content="text/html; charset=UTF-8">
<title>个人主页</title>
</head>
<body>
<%
     User user = (User)request.getAttribute("login");
%>
     <div align="center"><%=user.getUsername() %>,你好</div><br>
     <div align="center">当前没有更多服务内容</div>
     <a href="menu.jsp">退出账户</a>
</body>
</html>

验证截图:

主界面:

点击注册:

点击提交后:

返回主界面后,选择登陆:

登陆成功后界面:

点击退出账户后，会返回主界面

三、讲讲目标和计划

其实我个人没什么别的想法，也谈不上有什么计划，目前的想法就是课下靠自己学习Java web的技术，能够形成独立构建网站的能力。

现在的想法是每天至少得投入两个到三个小时学习Java web的内容，这需要耐心，我得慢慢来。

------------------------------------------------------------------------------------------------------------------------------------------------------------

END

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原文地址：https://www.cnblogs.com/messi2017/p/7885582.html