By their knowledge Dachu the basic framework of mission requirements, the completion of the import preceding input data into the database, the next step going to write after login interface, different identities correspond to different login screen, there are different buttons for different functions. The following is the source code:
java code:
package com.wyt.jdbcu;
import java.io.IOException;
import java.io.InputStream;
import java.util.Properties;
JDBCUtils class {public
// static block of statements
static {
//JDBCUtils.calss obtaining target
// getClassLoader () class loader
//getResourceAsStream("db.properties ") load the resource file into the input stream
InputStream is = JDBCUtils.class . .getClassLoader () the getResourceAsStream ( "the db.properties");
// Create Object type Properties
Properties P = new new Properties ();
// stream file loading
the try {
p.load (IS);
String = p.getProperty Driver ( " driver ");
// loading drive
the Class.forName (driver);
System.out.println (" drivers loaded successfully ");
} the catch (Exception E) {
// the TODO Auto-Generated Block the catch
e.printStackTrace ();
}
}
}
package com.wyt.dao;
import java.sql.Connection;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
import java.util.ArrayList;
import java.util.List;
com.hjf.entity.Course amount;
com.hjf.util.DBUtil amount;
/ **
* courses Dao
* Dao operation data layer
* @author Hu
*
* /
public class CourseDao {
/**
* 添加
* @param course
* @return
*/
public boolean add(Course course) {
String sql = "insert into text(name, password, sf) values('" + course.getName() + "','" + course.getPassword() + "','" + course.getSf() + "')";
//创建数据库链接
Connection conn = DBUtil.getConn();
Statement state = null;
boolean f = false;
int a = 0;
try {
state = conn.createStatement();
state.executeUpdate(sql);
} catch (Exception e) {
e.printStackTrace();
} finally {
//关闭连接
DBUtil.close(state, conn);
}
if (a > 0) {
f = true;
}
return f;
}
/**
* 删除
*
* @param id
* @return
*/
public boolean delete (int id) {
boolean f = false;
String sql = "delete from text where id='" + id + "'";
Connection conn = DBUtil.getConn();
Statement state = null;
int a = 0;
try {
state = conn.createStatement();
a = state.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUtil.close(state, conn);
}
if (a > 0) {
f = true;
}
return f;
}
/**
* 修改
* @param name
* @param pass
*/
public boolean update(Course course) {
String sql = "update text set name='" + course.getName() + "', password='" + course.getPassword() + "', sf='" + course.getSf()
+ "' where id='" + course.getId() + "'";
Connection conn = DBUtil.getConn();
Statement state = null;
boolean f = false;
int a = 0;
try {
state = conn.createStatement();
a = state.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUtil.close(state, conn);
}
if (a > 0) {
f = true;
}
return f;
}
/**
* 验证课程名称是否唯一
* true --- 不唯一
* @param name
* @return
*/
public boolean name(String name) {
boolean flag = false;
String sql = "select name from text where name = '" + name + "'";
Connection conn = DBUtil.getConn();
Statement state = null;
ResultSet rs = null;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
while (rs.next()) {
flag = true;
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUtil.close(rs, state, conn);
}
return flag;
}
/**
* 通过ID得到课程信息
* @param id
* @return
*/
public Course getCourseById(int id) {
String sql = "select * from text where id ='" + id + "'";
Connection conn = DBUtil.getConn();
Statement state = null;
ResultSet rs = null;
Course course = null;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
while (rs.next()) {
String name = rs.getString("name");
String password = rs.getString("password");
String sf = rs.getString("sf");
course = new Course(id, name, password, sf);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
DBUtil.close(rs, state, conn);
}
return course;
}
/**
* 通过name得到Course
* @param name
* @return
*/
public Course getCourseByName(String name) {
String sql = "select * from text where name ='" + name + "'";
Connection conn = DBUtil.getConn();
Statement state = null;
ResultSet rs = null;
Course course = null;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
while (rs.next()) {
int id = rs.getInt("id");
String password= rs.getString("password");
String sf = rs.getString("sf");
course = new Course(id, name, password, sf);
}
} catch (Exception e) {
e.printStackTrace();
} finally {
DBUtil.close(rs, state, conn);
}
return course;
}
/**
* 查找
* @param name
* @param teacher
* @param classroom
* @return
*/
public List<Course> search(String name, String password, String sf) {
String sql = "select * from text where ";
if (name != "") {
sql += "name like '%" + name + "%'";
}
if (password != "") {
sql += "password like '%" + password + "%'";
}
if (sf != "") {
sql += "sf like '%" + sf + "%'";
}
List<Course> list = new ArrayList<>();
Connection conn = DBUtil.getConn();
Statement state = null;
ResultSet rs = null;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
Course bean = null;
while (rs.next()) {
int id = rs.getInt("id");
String name2 = rs.getString("name");
String password2 = rs.getString("password");
String sf2 = rs.getString("sf");
bean = new Course(id, name2, password2, sf2);
list.add(bean);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUtil.close(rs, state, conn);
}
return list;
}
/**
* 全部数据
* @param name
* @param teacher
* @param classroom
* @return
*/
public List<Course> list() {
String sql = "select * from text";
List<Course> list = new ArrayList<>();
Connection conn = DBUtil.getConn();
Statement state = null;
ResultSet rs = null;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
Course bean = null;
while (rs.next()) {
int id = rs.getInt("id");
String name2 = rs.getString("name");
String password2 = rs.getString("password");
String sf2 = rs.getString("sf");
bean = new Course(id, name2, password2, sf2);
list.add(bean);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUtil.close(rs, state, conn);
}
return list;
}
}
package com.wyt.bl;
public class Course {
private int id;
private String name;
private String password;
private String sf;
public int getId() {
return id;
}
public void setId(int id) {
this.id = id;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public String getSf() {
return sf;
}
public void setSf(String sf) {
this.sf = sf;
}
public Course() {}
public Course(int id, String name, String password, String sf) {
this.id = id;
this.name = name;
this.password = password;
this.sf = sf;
}
public Course(String name, String password, String sf) {
this.name = name;
this.password = password;
this.sf = sf;
}
}
package com.wyt.service;
import java.util.List;
import com.hjf.dao.CourseDao;
import com.hjf.entity.Course;
/ **
* CourseService
* service layer
* @author Hu
*
* /
public class {CourseService
CourseDao cDao = new CourseDao();
/**
* 添加
* @param course
* @return
*/
public boolean add(Course course) {
boolean f = false;
if(!cDao.name(course.getName())) {
cDao.add(course);
f = true;
}
return f;
}
/**
* 删除
*/
public void del(int id) {
cDao.delete(id);
}
/**
* 修改
* @return
*/
public void update(Course course) {
cDao.update(course);
}
/**
* 通过ID得到一个Course
* @return
*/
public Course getCourseById(int id) {
return cDao.getCourseById(id);
}
/**
* 通过Name得到一个Course
* @return
*/
public Course getCourseByName(String name) {
return cDao.getCourseByName(name);
}
/**
* 查找
* @return
*/
public List<Course> search(String name, String password, String sf) {
return cDao.search(name, password,sf);
}
/**
* 全部数据
* @return
*/
public List<Course> list() {
return cDao.list();
}
}
package com.wyt.util;
import java.sql.Connection;
import java.sql.DriverManager;
import java.sql.PreparedStatement;
import java.sql.ResultSet;
import java.sql.SQLException;
import java.sql.Statement;
public class DBUtil {
public static String db_url = "jdbc:mysql://localhost:3306/data?characterEncoding=utf8";
public static String db_user = "root";
public static String db_pass = "zhangxinyue520";
public static Connection getConn () {
Connection conn = null;
try {
Class.forName("com.mysql.jdbc.Driver");
conn = DriverManager.getConnection(db_url, db_user, db_pass);
} catch (Exception e) {
e.printStackTrace();
}
return conn;
}
public static void close (Statement state, Connection conn) {
if (state != null) {
try {
state.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
public static void close (ResultSet rs, Statement state, Connection conn) {
if (rs != null) {
try {
rs.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (state != null) {
try {
state.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
if (conn != null) {
try {
conn.close();
} catch (SQLException e) {
e.printStackTrace();
}
}
}
public static void main(String[] args) throws SQLException {
Connection conn = getConn();
PreparedStatement pstmt = null;
ResultSet rs = null;
String sql ="select * from text";
pstmt = conn.prepareStatement(sql);
rs = pstmt.executeQuery();
if(rs.next()){
System.out.println("欧了");
}else{
System.out.println("再试试");
}
}
}
package com.wyt.jdbc;
the JDBC class {public
public static void main (String args []) {
the try {
the Class.forName ( "com.mysql.jdbc.Driver");
System.out.println ( "drivers loaded successfully");
} the catch (E a ClassNotFoundException ) {
e.printStackTrace ();
System.out.println ( "driver failed to load");
}
}
}
package com.wyt.servlet;
import java.io.IOException;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import com.hjf.entity.Course;
import com.hjf.service.CourseService;
@WebServlet("/CourseServlet")
public class CourseServlet extends HttpServlet {
private static final long serialVersionUID = 1L;
CourseService service = new CourseService();
/**
* 方法选择
*/
protected void service(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
req.setCharacterEncoding("utf-8");
String method = req.getParameter("method");
if ("add".equals(method)) {
add(req, resp);
} else if ("del".equals(method)) {
del(req, resp);
} else if ("update".equals(method)) {
update(req, resp);
} else if ("search".equals(method)) {
search(req, resp);
} else if ("getcoursebyid".equals(method)) {
getCourseById(req, resp);
} else if ("getcoursebyname".equals(method)) {
getCourseByName(req, resp);
} else if ("list".equals(method)) {
list(req, resp);
}
}
private void add(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException {
req.setCharacterEncoding("utf-8");
//获取数据
String name = req.getParameter("name");
String password = req.getParameter("password");
String sf = req.getParameter("sf");
Course course = new Course(name, password, sf);
//添加后消息显示
if(service.add(course)) {
req.setAttribute("message", "添加成功");
req.getRequestDispatcher("denglu1.jsp").forward(req,resp);
} else {
req.setAttribute("message", "用户已存在，请重新录入");
req.getRequestDispatcher("zhuce.jsp").forward(req,resp);
}
}
/**
* 全部
* @param req
* @param resp
* @throws ServletException
*/
private void list(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
List<Course> courses = service.list();
req.setAttribute("courses", courses);
req.getRequestDispatcher("list.jsp").forward(req,resp);
}
/**
* 通过ID得到Course
* @param req
* @param resp
* @throws ServletException
*/
private void getCourseById(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
int id = Integer.parseInt(req.getParameter("id"));
Course course = service.getCourseById(id);
req.setAttribute("course", course);
req.getRequestDispatcher("detail2.jsp").forward(req,resp);
}
/**
* 通过名字查找
* 跳转至删除
* @param req
* @param resp
* @throws IOException
* @throws ServletException
*/
private void getCourseByName(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
String name = req.getParameter("name");
Course course = service.getCourseByName(name);
if(course == null) {
req.setAttribute("message", "查无此人！");
req.getRequestDispatcher("del.jsp").forward(req,resp);
} else {
req.setAttribute("course", course);
req.getRequestDispatcher("detail.jsp").forward(req,resp);* Delete/ **}
}
* @param req
* @param resp
* @throws IOException
* @throws ServletException
*/
private void del(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
int id = Integer.parseInt(req.getParameter("id"));
service.del(id);
req.setAttribute("message", "删除成功！");
req.getRequestDispatcher("del.jsp").forward(req,resp);
}
/**
* 修改
* @param req
* @param resp
* @throws IOException
* @throws ServletException
*/
private void update(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
int id = Integer.parseInt(req.getParameter("id"));
String name = req.getParameter("name");
String password = req.getParameter("password");
String sf = req.getParameter("sf");
Course course = new Course(id, name, password, sf);
service.update(course);
req.setAttribute("message", "修改成功");
req.getRequestDispatcher("CourseServlet?method=list").forward(req,resp);
}
/**
* 查找
* @param req
* @param resp
* @throws ServletException
*/
private void search(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
String name = req.getParameter("name");
String password = req.getParameter("password");
String sf = req.getParameter("sf");
List<Course> courses = service.search(name, password, sf);
req.setAttribute("courses", courses);
req.getRequestDispatcher("searchlist.jsp").forward(req,resp);
}
}
jsp code:
home page:
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>登陆or注册</title>
</head>
<body>
<a href="denglu1.jsp">用户登录</a>
<a href="zhuce.jsp">用户注册</a>
</body>
</html>
registration page:
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>用户注册</title>
</head>
<body>
<%
Object message = request.getAttribute("message");
if(message!=null && !"".equals(message)){
%>
<script type="text/javascript">
alert("<%=request.getAttribute("message")%>");
</script>
<%} %>
<div align="center">
<h1 style="color: black;">身份注册</h1>
<a href="denglu.jsp">返回主页</a>
<form action="CourseServlet?method=add" method="post" onsubmit="return check()">
<div class="a">
用户名<input type="text" id="name" name="name"/>
</div>
<div class="a">
密 码<input type="password" id="password" name="password" />
</div>
<div class="a">
身 份<input type="text" id="sf" name="sf" />
</div>
<div class="a">
<button type="submit" class="b">提 交</button>
</div>
</form>
</div>
<script type="text/javascript">Alert ( 'user name can not be empty');if (name. == value '') {// not emptyvar SF = document.getElementById ( "SF");var = document.getElementById password ( "password");var name = document.getElementById ( "name") ;;
Check function () {
name.focus ();
return to false;
}
IF (password.value == '') {
Alert ( 'password is not blank');
password.focus ();
return to false;
}
IF (sf.value == '' ) {
Alert ( 'identification information can not be empty');
sf.focus ();
return to false;
}
}
</ Script>
</ body>
</ HTML>
log in page:
<%@ page language="java" contentType="text/html; charset=utf-8"
pageEncoding="utf-8"%>
<!DOCTYPE html>
<html>
<head>
<meta charset="utf-8">
<title>用户登录</title>
</head>
<body>
<%
Object message = request.getAttribute("message");
if(message!=null && !"".equals(message)){
%>
<script type="text/javascript">
alert("<%=request.getAttribute("message")%>");
</script>
<%} %>
<div align="center">
<h1 style="color: black;">用户登录</h1>
<a href="denglu.jsp">返回主页</a>
<form action="CourseServlet?method=search" method="post" onsubmit="return check()">
<div class="a">
用户名<input type="text" id="name" name="name"/>
</div>
<div class="a">
密 码<input type="text" id="password" name="password" />
</div>
<div class="a">
<button type="submit" class="b">登 陆</button>
</div>
</form>
</div>
<script type="text/javascript">
function check() {
var name = document.getElementById("name");;
var password = document.getElementById("password");
//非空
if(name.value == '') {
alert('Username empty '); </ Script>}}return to false;Alert (' empty password ');IF (password.value ==' ') {}
return to false;
</body>
</html>
Since searchlist page after landing did not write so 404s After clicking Sign - indicate the source server could not find the target resource or is unwilling to open an existing resource representation.
The next step will focus on the whole idea, write out one by one to display different pages to different users after landing after modeling, the "identity" of the conditions to judge.