标签:ret date 建立 tps doctype 错误信息 中断 dao page
1程序设计思想
首先在addInput.jsp 界面中完成网页界面的设计,进行网页测试,看是否完成设计,然后在数据库中建立表,在daoimpi 类文件中进行数据的链接,进行测试,在add.jsp文件中进行判断输入的字符是否合法,建立一个自定义异常类ClassException,在try 中进行输入字符的判断,然后进行抛出异常,最后catch异常,用标签将错误原因显示在网页上
2源程序代码
IUserDao.java
package com.jaovo.msg.dao; import com.jaovo.msg.mobeI.User; public interface IUserDao { public void add(User user);//添加 }
UserdaoImpI.java 数据库的链接
package com.jaovo.msg.dao;//实现方法的类 import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import java.sql.Connection; import com.jaovo.msg.Util.DBUtil; import com.jaovo.msg.Util.UserException; import com.jaovo.msg.mobeI.User; public class UserdaoImpI implements IUserDao {//实现接口中的所有方法 6步 @SuppressWarnings("resource") @Override public void add(User user) {//增加的方法 // TODO Auto-generated method stub Connection connection=DBUtil.getConnection();//获得连接对象 //准备sql语句 String sql = "select count(*) from t_user where username = ?";//count 数据的条数 //创建语句传输对象 PreparedStatement preparedStatement = null; ResultSet resultSet = null;// try { preparedStatement = connection.prepareStatement(sql); preparedStatement.setString(1, user.getKecheng()); resultSet = preparedStatement.executeQuery();//接受一下结果集 //遍历结果集 while(resultSet.next()) { if(resultSet.getInt(1) > 0) { throw new UserException("用户已存在") ; }; } sql = "insert into t_user(username,password,nickname) values (?,?,?)"; preparedStatement = connection.prepareStatement(sql); preparedStatement.setString(1, user.getKecheng()); preparedStatement.setString(2, user.getTeacher()); preparedStatement.setString(3, user.getAdress()); preparedStatement.executeUpdate(); } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); }finally { DBUtil.close(resultSet); DBUtil.close(preparedStatement); DBUtil.close(connection); } } }
User。Java
package com.jaovo.msg.mobeI; public class User { private int id; private String kecheng; private String teacher; private String adress; public int getId() { return id; } public void setId(int id) { this.id = id; } public String getKecheng() { return kecheng; } public void setKecheng(String kecheng) { this.kecheng = kecheng; } public String getAdress() { return adress; } public void setAdress(String adress) { this.adress = adress; } public String getTeacher() { return teacher; } public void setTeacher(String teacher) { this.teacher = teacher; } }
ClassException.java
package com.jaovo.msg.Util; public class ClassException extends Exception{ /** * */ private static final long serialVersionUID = 1L; public ClassException() { super(); // TODO Auto-generated constructor stub } public ClassException(String message, Throwable cause, boolean enableSuppression, boolean writableStackTrace) { super(message, cause, enableSuppression, writableStackTrace); // TODO Auto-generated constructor stub } public ClassException(String message, Throwable cause) { super(message, cause); // TODO Auto-generated constructor stub } public ClassException(String message) { super(message); // TODO Auto-generated constructor stub } public ClassException(Throwable cause) { super(cause); // TODO Auto-generated constructor stub } }
DBUtil.java
package com.jaovo.msg.Util;//链接数据库的方法 /* 1加载驱动 2创建连接对象 3创建语句传输对象 4接受结果集对象 5遍历 6关闭资源 */ import java.sql.Connection; import java.sql.DriverManager; import java.sql.PreparedStatement; import java.sql.ResultSet; import java.sql.SQLException; import org.apache.tomcat.dbcp.dbcp2.DriverManagerConnectionFactory; public class DBUtil { public static Connection getConnection() { //1.加载驱动 try { Class.forName("com.mysql.jdbc.Driver").newInstance(); } catch (InstantiationException | IllegalAccessException | ClassNotFoundException e) { // TODO Auto-generated catch block e.printStackTrace(); } String user = "root"; String password = "root"; String url = "jdbc:mysql://localhost:3306/jaovo_msg?useUnicode=true&characterEncoding=UTF-8";//连接数据库的代码 Connection connection = null;//提升定域 try { //2创建连接对象 connection = DriverManager.getConnection(url,user,password);//连接数据库的对象 } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } return connection; } //关闭资源方法 public static void close(Connection connection) {//连接对象的关闭 try { if(connection != null) {//空指针异常 connection.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static void close(PreparedStatement preparedStatement) {//语句传输对象关闭 try { if(preparedStatement != null) { preparedStatement.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } public static void close(ResultSet resultSet) {//关闭结果集对象 主要针对查询的对象 try { if(resultSet != null) { resultSet.close(); } } catch (SQLException e) { // TODO Auto-generated catch block e.printStackTrace(); } } }
ValidateUtil.java
package com.jaovo.msg.Util; import java.util.HashMap; import java.util.Map; import javax.servlet.http.HttpServletRequest; public class ValidateUtil { public static boolean validateNull(HttpServletRequest request,String[] fileds) { boolean validate=true; //Map对象用来装载不同的错误信息 Map<String,String>errorMsg=new HashMap(); for(String filed:fileds) { String value=request.getParameter(filed); if(value==null||"".equals(value.trim())) { validate=false; errorMsg.put(filed, filed+"不能为空"); } if(!validate) { request.setAttribute("errormsg",errorMsg); } } return validate; } }
add.jsp
<%@page import="com.jaovo.msg.Util.ClassException"%> <%@page import="com.jaovo.msg.Util.UserException"%> <%@page import="com.jaovo.msg.dao.UserdaoImpI"%> <%@page import="com.jaovo.msg.mobeI.User"%> <%@ page language="java" contentType="text/html; charset=UTF-8" pageEncoding="UTF-8"%> <!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd "> <html> <% //接受客户端传递过来的参数 request.setCharacterEncoding("UTF-8"); String kecheng = request.getParameter("kecheng"); String teacher = request.getParameter("teacher"); String adress = request.getParameter("adress"); try{ if(!teacher.trim().equals("王建民")&&!teacher.trim().equals("刘立嘉")&&!teacher.trim().equals("刘丹")&&!teacher.trim().equals("杨子光")&&!teacher.trim().equals("王辉")) { throw new ClassException("不能输入"); } else if (!adress.trim().startsWith("基教")&&!adress.trim().startsWith("一教")&&!adress.trim().startsWith("二教")&&!adress.trim().startsWith("三教")) { throw new ClassException("不能输入"); } else { User user = new User(); user.setKecheng(kecheng); user.setTeacher(teacher); user.setAdress(adress); UserdaoImpI userDao = new UserdaoImpI(); userDao.add(user); %> <body> 用户保存成功!!<br> <a href="addInput.jsp">继续添加</a><br> <a href="#">用户列表</a> <% } } catch(ClassException e){ %> <h2 style="color:red ; font-size:50px">发生错误 : <%=e.getMessage() %></h2> <% } %> </html>
addInput.jsp
<%@ page language="java" contentType="text/html; charset=UTF-8"
pageEncoding="UTF-8"%>
<!DOCTYPE html PUBLIC "-//W3C//DTD HTML 4.01 Transitional//EN" "http://www.w3.org/TR/html4/loose.dtd
">
<html>
<head>
<title>课程添加界面</title>
</head>
<body>
<form action = "add.jsp" method = "post">
<table align = "center" border="1" width="500" >
<tr>
<td>课程名称:</td>
<td>
<input type ="text" name = "kecheng"/>
</td>
</tr>
<tr>
<td>任课教师:</td>
<td>
<input type = "text" name = "teacher"/>
</td>
<tr>
<td>上课地点:</td>
<td>
<input type = "text" name = "adress" />
</td>
</tr>
<tr align="center">
<td colspan = "2">
<input type = "submit" value = "保存"/>
</td>
</table>
</form>
</body>
</html>
程序执行结果截图
psp日志
日期 |
开始时间 |
结束时间 |
中断时间 |
净时间 |
活动 |
备注 |
C |
U |
2017.11.28 |
13.00 |
15.00 |
2.30 |
110分钟 |
休息 |
|
|
|
|
15.00 |
15.40 |
|
40 |
开班会 |
进行学习十九大 |
|
|
|
16.00 |
17.30 |
|
90 |
编程 |
|
|
|
|
17.30 |
17.50 |
|
30 |
吃饭 |
|
|
|
|
18.00 |
18.40 |
|
|
休息,聊天 |
|
|
|
|
18.40 |
21.00 |
20.00 |
110 |
编程 |
准备考试
|
|
总结:在进行有关项目的编码是,需要注意编程上的规范,在写完每一个部分之后都需要进行测试,防止程序出现不可逆转的错误,加大程序完成的效率,将时间更多的用来学习只是和巩固住已经学习的知识。
标签:ret date 建立 tps doctype 错误信息 中断 dao page
原文地址:http://www.cnblogs.com/xuzhaoyang/p/7911383.html