20201120千锤百炼软工人
今天帮同学看了看一个学生管理系统
部分代码如下
package 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;
import Bean.Administrator;
import Bean.Student;
import DBUitl.DBUitl;
import DBUitl.DBUitl;
public class Dao {
//
public static boolean Adenglu(Administrator A) {
boolean f = false;
String sql = "select * from administrator where id = '" + A.getId() + "' and password = '"+ A.getPassword() +"'";
//
Connection conn = DBUitl.getConn();
Statement state = null;
ResultSet rs = null;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
if (rs.next()) {
f = true;
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(rs, state, conn);
}
return f;
}
public static boolean addadmin(Administrator a) {
boolean f = false;
String sql = "insert into administrator(name,id,password) values('" + a.getName() + "','" + a.getId() + "','" + a.getPassword() + "')";
//
Connection conn = DBUitl.getConn();
Statement state = null;
int b = 0;
try {
state = conn.createStatement();
b = state.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(state, conn);
}
if (b > 0) {
f = true;
}
return f;
}
public static boolean deleteA(Administrator a) {
boolean f = false;
String sql = "delete from administrator where id='" + a.getId() + "'";
Connection conn = DBUitl.getConn();
Statement state = null;
int b = 0;
try {
state = conn.createStatement();
b = state.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(state, conn);
}
if (b > 0) {
f = true;
}
return f;
}
public static boolean updateA(Administrator A) {
String sql = "update administrator set name='" + A.getName() + "', password='" + A.getPassword() + "' where id='" + A.getId() + "'";
Connection conn = DBUitl.getConn();
Statement state = null;
boolean f = false;
int a = 0;
try {
state = conn.createStatement();
a = state.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(state, conn);
}
if (a > 0) {
f = true;
}
return f;
}
public static boolean addstudent(Student student) {
boolean f = false;
String sql = "insert into student(name,idc,sex,college,class) values('" + student.getName() + "','" + student.getIdc() + "','" + student.getSex() + "','" + student.getCollege() + "','" + student.getClass1() + "')";
//
Connection conn = DBUitl.getConn();
Statement state = null;
int a = 0;
try {
state = conn.createStatement();
a = state.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(state, conn);
}
if (a > 0) {
f = true;
}
return f;
}
public static boolean deleteS(Student a) {
boolean f = false;
String sql = "delete from student where idc='" + a.getIdc() + "'";
Connection conn = DBUitl.getConn();
Statement state = null;
int b = 0;
try {
state = conn.createStatement();
b = state.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(state, conn);
}
if (b > 0) {
f = true;
}
return f;
}
public static boolean updateS(Student A) {
String sql = "update student set name='" + A.getName() + "', college='" + A.getCollege() + "', class='" + A.getClass1() + "', sex='" + A.getSex() + "' where idc='" + A.getIdc() + "'";
Connection conn = DBUitl.getConn();
Statement state = null;
boolean f = false;
int a = 0;
try {
state = conn.createStatement();
a = state.executeUpdate(sql);
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(state, conn);
}
if (a > 0) {
f = true;
}
return f;
}
public static List<Student> search(String name,String class1) {
String sql = "select * from student where ";
if (name != "") {
sql += "name like '%" + name + "%'";
}
else if (class1 != "") {
sql += "class like '%" + class1 + "%'";
}
else
{
}
List<Student> list = new ArrayList<>();
Connection conn = DBUitl.getConn();
Statement state = null;
ResultSet rs = null;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
while (rs.next()) {
String idc = rs.getString("idc");
String name2 = rs.getString("name");
String college = rs.getString("college");
String class2 = rs.getString("class");
String sex2 = rs.getString("sex");
Student S = new Student();
S.setClass1(class2);
S.setCollege(college);
S.setIdc(idc);
S.setName(name2);
S.setSex(sex2);
list.add(S);
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(rs, state, conn);
}
return list;
}
public static int jisuancollege(String college) {
String sql = "select * from student where college like '%" + college + "%'";
Connection conn = DBUitl.getConn();
Statement state = null;
ResultSet rs = null;
int i=0;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
while (rs.next()) {
i++;
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(rs, state, conn);
}
return i;
}
public static int jisuansex(String sex) {
String sql = "select * from student where sex like '%" + sex + "%'";
Connection conn = DBUitl.getConn();
Statement state = null;
ResultSet rs = null;
int i=0;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
while (rs.next()) {
i++;
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(rs, state, conn);
}
return i;
}
public static int jisuanclass(String class1) {
String sql = "select * from student where class like '%" + class1 + "%'";
Connection conn = DBUitl.getConn();
Statement state = null;
ResultSet rs = null;
int i=0;
try {
state = conn.createStatement();
rs = state.executeQuery(sql);
while (rs.next()) {
i++;
}
} catch (SQLException e) {
e.printStackTrace();
} finally {
DBUitl.close(rs, state, conn);
}
return i;
}
}
package servlet;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;
import javax.servlet.ServletException;
import javax.servlet.annotation.WebServlet;
import javax.servlet.http.Cookie;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import Dao.Dao;
import Bean.Administrator;
import Bean.Student;
@WebServlet("/servlet")
public class servlet extends HttpServlet {
private static final long serialVersionUID = 1L;
/**
* @see HttpServlet#HttpServlet()
*/
protected void service(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
request.setCharacterEncoding("utf-8");
String method = request.getParameter("method");
if ("denglu".equals(method)) {
denglu(request, response);
}
else if ("addadmin".equals(method)) {
addadmin(request, response);
}
else if ("deleteA".equals(method)) {
deleteA(request, response);
}
else if ("updateA".equals(method)) {
updateA(request, response);
}
else if ("addstudent".equals(method)) {
addstudent(request, response);
}
else if ("deleteS".equals(method)) {
deleteS(request, response);
}
else if ("updateS".equals(method)) {
updateS(request, response);
}
else if ("search".equals(method)) {
search(request, response);
}
else if ("jisuan".equals(method)) {
jisuan(request, response);
}
}
private void denglu(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
request.setCharacterEncoding("utf-8");
String idc = request.getParameter("id");
String password = request.getParameter("password");
Administrator A = new Administrator(idc,password);
if(Dao.Adenglu(A))
{
request.setAttribute("message", "登录成功");
Cookie cookie = new Cookie("id",idc);
response.addCookie(cookie);
response.sendRedirect("menu1.jsp");
}
else
{
request.setAttribute("message", "登录失败");
response.sendRedirect("begin.jsp");
}
}
private void addadmin(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
request.setCharacterEncoding("utf-8");
String name = request.getParameter("name");
String password = request.getParameter("password");
String idc = request.getParameter("idc");
Administrator a = new Administrator(name,idc,password);
if(Dao.addadmin(a)) {
request.setAttribute("message", "添加管理员信息成功");
request.getRequestDispatcher("menu1.jsp").forward(request,response);
} else {
request.setAttribute("message", "添加管理员信息失败");
request.getRequestDispatcher("menu1.jsp").forward(request,response);
}
}
private void deleteA(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
request.setCharacterEncoding("utf-8");
String idc = request.getParameter("idc");
Administrator a = new Administrator(idc);
if(Dao.deleteA(a)) {
request.setAttribute("message", "删除管理员信息成功");
request.getRequestDispatcher("menu1.jsp").forward(request,response);
} else {
request.setAttribute("message", "删除管理员信息失败");
request.getRequestDispatcher("menu1.jsp").forward(request,response);
}
}
private void updateA(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
boolean a = false;
String id = req.getParameter("id");
String name = req.getParameter("name");
String password = req.getParameter("password");
Administrator A = new Administrator();
A.setId(id);
A.setName(name);
A.setPassword(password);
a = Dao.updateA(A);
if(a)
{
req.setAttribute("message", "修改成功");
req.getRequestDispatcher("menu1.jsp").forward(req,resp);
}
else
{
req.setAttribute("message", "修改失败");
req.getRequestDispatcher("menu1.jsp").forward(req,resp);
}
}
private void addstudent(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
request.setCharacterEncoding("utf-8");
String name = request.getParameter("name");
String idc = request.getParameter("idc");
String class1 = request.getParameter("class1");
String sex = request.getParameter("sex");
String major = request.getParameter("major");
Student student = new Student();
student.setClass1(class1);
student.setCollege(major);
student.setIdc(idc);
student.setName(name);
student.setSex(sex);
if(Dao.addstudent(student)) {
request.setAttribute("message", "添加学生信息成功");
request.getRequestDispatcher("menu1.jsp").forward(request,response);
} else {
request.setAttribute("message", "添加学生信息失败");
request.getRequestDispatcher("menu1.jsp").forward(request,response);
}
}
private void deleteS(HttpServletRequest request, HttpServletResponse response) throws IOException, ServletException {
request.setCharacterEncoding("utf-8");
String idc = request.getParameter("idc");
Student a = new Student();
a.setIdc(idc);
if(Dao.deleteS(a)) {
request.setAttribute("message", "删除学生信息成功");
request.getRequestDispatcher("menu1.jsp").forward(request,response);
} else {
request.setAttribute("message", "删除学生信息失败");
request.getRequestDispatcher("menu1.jsp").forward(request,response);
}
}
private void updateS(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
boolean a = false;
String id = req.getParameter("idc");
String name = req.getParameter("name");
String college = req.getParameter("college");
String class1 = req.getParameter("class");
String sex = req.getParameter("sex");
Student A = new Student();
A.setIdc(id);
A.setName(name);
A.setCollege(college);
A.setSex(sex);
A.setClass1(class1);
a = Dao.updateS(A);
if(a)
{
req.setAttribute("message", "修改成功");
req.getRequestDispatcher("menu1.jsp").forward(req,resp);
}
else
{
req.setAttribute("message", "修改失败");
req.getRequestDispatcher("menu1.jsp").forward(req,resp);
}
}
private void search(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
List<Student> list = new ArrayList<>();
String name = req.getParameter("name");
String class1 = req.getParameter("class");
list = Dao.search(name,class1);
req.setAttribute("students", list);
req.getRequestDispatcher("list.jsp").forward(req,resp);
}
private void jisuan(HttpServletRequest req, HttpServletResponse resp) throws IOException, ServletException{
req.setCharacterEncoding("utf-8");
String sex = req.getParameter("sex");
String class1 = req.getParameter("class");
String college = req.getParameter("major");
int[] a = new int[3];
a[0]=Dao.jisuancollege(college);
a[1]=Dao.jisuansex(sex);
a[2]=Dao.jisuanclass(class1);
req.setAttribute("jisuan", a);
req.setAttribute("sex", sex);
req.setAttribute("class1", class1);
req.setAttribute("college", college);
req.getRequestDispatcher("list1.jsp").forward(req,resp);
}
protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
doGet(request, response);
}
/**
* @see HttpServlet#doGet(HttpServletRequest request, HttpServletResponse response)
*/
protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
// TODO Auto-generated method stub
response.getWriter().append("Served at: ").append(request.getContextPath());
}
/**
* @see HttpServlet#doPost(HttpServletRequest request, HttpServletResponse response)
*/
}
package Bean;
public class Administrator {
String name;
String id;
String password;
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getId() {
return id;
}
public void setId(String id) {
this.id = id;
}
public String getPassword() {
return password;
}
public void setPassword(String password) {
this.password = password;
}
public Administrator() {
}
public Administrator(String name,String id,String password) {
this.id=id;
this.name=name;
this.password=password;
}
public Administrator(String id) {
this.id=id;
}
public Administrator(String id,String password) {
this.id=id;
this.password=password;
}
}
package Bean;
public class Student {
String idc;
String name;
String college;
String class1;
String sex;
public String getIdc() {
return idc;
}
public void setIdc(String idc) {
this.idc = idc;
}
public String getName() {
return name;
}
public void setName(String name) {
this.name = name;
}
public String getCollege() {
return college;
}
public void setCollege(String college) {
this.college = college;
}
public String getClass1() {
return class1;
}
public void setClass1(String class1) {
this.class1 = class1;
}
public String getSex() {
return sex;
}
public void setSex(String sex) {
this.sex = sex;
}
public Student(String idc)
{
this.idc=idc;
}
public Student()
{
}
}
