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基于web的简单信息管理系统

前言

该项目是一个基于jsp的基本小项目，可以实现登录功能和基本的增删改查。

一、项目需求

1.将准备好的html页面修改成jsp。
2.实现管理员登录功能，并应用权限验证。
3.对员工实现增删改查。
4.查询员工使用分页查询，并提供首页，尾页。上页，下一页。

二、项目搭建

项目目录搭建

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2.项目资源引入

创建项目导入相关的jar文件。
在这里插入图片描述

3.数据库的创建

在这里插入图片描述

4.项目开发

仅展示关键代码，其他代码戳我。

用户登录的controller

代码如下（示例）：

package com.controller;


import com.entity.EmpManager;
import com.service.EmpManagerService;
import com.service.impl.EmpManagerServiceImpl;

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 javax.servlet.http.HttpSession;
import java.io.IOException;

@WebServlet(name = "EmpManagerLoginController",value = "/manager/loginController")
public class EmpManagerLoginController extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        //1.收参
        String username = request.getParameter("username");
        String password = request.getParameter("password");
        String inputVcode = request.getParameter("inputVcode");

        //2.校验验证码
        String codes = (String)request.getSession().getAttribute("codes");
        if(!inputVcode.isEmpty() && inputVcode.equalsIgnoreCase(codes)){
            //调用业务逻辑实现登录
            EmpManagerService empManagerService = new EmpManagerServiceImpl();
            EmpManager empManager = empManagerService.login(username,password);
            if(empManager!=null){
                //登录成功
                //存储在session作用域
                HttpSession session = request.getSession();
                session.setAttribute("empManager",empManager);
                //跳转到查询所有的controller
                response.sendRedirect(request.getContextPath()+"/manager/safe/showall");
            }else{
                response.sendRedirect(request.getContextPath()+"/login.html");
            }
        }else{
            //验证码输入错误，跳转到登录页面
            response.sendRedirect(request.getContextPath()+"/login.html");
        }
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request,response);
    }
}
用上述的导入的jar文件创建的验证码controller

代码如下（示例）：

package com.controller;

import cn.dsna.util.images.ValidateCode;

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 javax.servlet.http.HttpSession;
import java.io.IOException;

@WebServlet(name = "CreateCodeController",value = "/createCode")
public class CreateCodeController extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        ValidateCode validateCode = new ValidateCode(200,30,4,10);
        String codes = validateCode.getCode();
        HttpSession session = request.getSession();
        session.setAttribute("codes",codes);

        validateCode.write(response.getOutputStream());
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }
}
分页查询的controller
package com.controller;
import com.entity.Emp;
import com.entity.Page;
import com.service.EmpService;
import com.service.impl.EmpServiceImpl;

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 java.io.IOException;
import java.util.List;

@WebServlet(name = "ShowAllEmpController",value = "/manager/safe/showall")
public class ShowAllEmpController extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        String pageIndex = request.getParameter("pageIndex");
        if(pageIndex == null){
            pageIndex="1";
        }

        Page page = new Page(Integer.valueOf(pageIndex));

        EmpService empService = new EmpServiceImpl();
        List<Emp> emps = empService.selectAll(page);

        request.setAttribute("emps",emps);
        request.setAttribute("page",page);

        request.getRequestDispatcher("/emplist.jsp").forward(request,response);
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }
}
分页在jsp中的核心代码实现如下
    <tr>
                    <td colspan="5" align="center">
                        <a href="<c:url context='${pageContext.request.contextPath}' value='/manager/safe/showall?pageIndex=1'/>">首页</a>

                        <c:if test="${page.pageIndex > 1}">
                            <a href="<c:url context='${pageContext.request.contextPath}' value='/manager/safe/showall?pageIndex=${page.pageIndex - 1}' />">上一页</a>
                        </c:if>
                        <c:if test="${page.pageIndex==1}">
                            <a>上一页</a>
                        </c:if>

                        <c:if test="${page.pageIndex < page.totalPages}">
                            <a href="<c:url context='${pageContext.request.contextPath}' value='/manager/safe/showall?pageIndex=${page.pageIndex + 1}' />">下一页</a>
                        </c:if>
                        <c:if test="${page.pageIndex == page.totalPages}">
                            <a>下一页</a>
                        </c:if>

                        <a href="<c:url context='${pageContext.request.contextPath}' value='/manager/safe/showall?pageIndex=${page.totalPages}'/>">尾页</a>
                    </td>
                </tr>
page页面的核心配置信息
public class Page {
    private Integer pageIndex;//当前页码

    private Integer pageSize;//页大小

    private Integer totalCounts;//数据总条数

    private Integer totalPages;//总页数

    private Integer startRows;//起始行

    public Page(Integer pageIndex) {
        this(pageIndex,5);
    }

    public Page(Integer pageIndex, Integer pageSize) {
        this.pageIndex = pageIndex;
        this.pageSize = pageSize;
        this.setStartRows((pageIndex - 1) * pageSize);
    }

    public Integer getPageIndex() {
        return pageIndex;
    }

    public void setPageIndex(Integer pageIndex) {
        this.pageIndex = pageIndex;
    }

    public Integer getPageSize() {
        return pageSize;
    }

    public void setPageSize(Integer pageSize) {
        this.pageSize = pageSize;
    }

    public Integer getTotalCounts() {
        return totalCounts;
    }

    public void setTotalCounts(Integer totalCounts) {
        this.totalCounts = totalCounts;

        this.setTotalPages(this.totalCounts % this.pageSize ==0? this.totalCounts / this.pageSize : this.totalCounts / this.pageSize + 1);
    }

    public Integer getTotalPages() {
        return totalPages;
    }

    public void setTotalPages(Integer totalPages) {
        this.totalPages = totalPages;
    }

    public Integer getStartRows() {
        return startRows;
    }

    public void setStartRows(Integer startRows) {
        this.startRows = startRows;
    }
}
添加员工的insertcontroller
package com.controller;

import com.entity.Emp;
import com.service.EmpService;
import com.service.impl.EmpServiceImpl;

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 java.io.IOException;

@WebServlet(value = "/manager/safe/insertemp")
public class InsertEmpController  extends HttpServlet {

    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        String name=req.getParameter("name");
        Double salary=Double.valueOf(req.getParameter("salary"));
        Integer age=Integer.valueOf(req.getParameter("age"));

        Emp emp=new Emp(name,salary,age);

        EmpService empService=new EmpServiceImpl();
        empService.insert(emp);

        resp.sendRedirect(req.getContextPath()+"/manager/safe/showall");
    }

    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
      doPost(req, resp);
    }
}
修改员工信息的controller
import com.entity.Emp;
import com.service.EmpService;
import com.service.impl.EmpServiceImpl;

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 java.io.IOException;


@WebServlet(name = "UpdateEmpController",value = "/manager/safe/updateEmp")
public class UpdateEmpController extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        Integer id = Integer.valueOf(request.getParameter("id"));
        String name = request.getParameter("name");
        Double salary = Double.valueOf(request.getParameter("salary"));
        Integer age = Integer.valueOf(request.getParameter("age"));

        Emp emp = new Emp(id,name,salary,age);

        EmpService empService = new EmpServiceImpl();
        empService.update(emp);

        response.sendRedirect(request.getContextPath()+"/manager/safe/showall");
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }
}
查询单个员工信息的controller
package com.controller;

import com.entity.Emp;
import com.service.EmpService;
import com.service.impl.EmpServiceImpl;

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 java.io.IOException;

@WebServlet(name = "ShowEmpController",value = "/manager/safe/showEmp")
public class ShowEmpController extends HttpServlet {
    protected void doPost(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        Integer id = Integer.valueOf(request.getParameter("id"));

        EmpService empService = new EmpServiceImpl();
        Emp emp = empService.select(id);


        request.setAttribute("emp",emp);


        request.getRequestDispatcher("/UpdateEmp.jsp").forward(request,response);
    }

    protected void doGet(HttpServletRequest request, HttpServletResponse response) throws ServletException, IOException {
        doPost(request, response);
    }
}
删除员工信息的contoller

import com.service.EmpService;
import com.service.impl.EmpServiceImpl;

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 java.io.IOException;

@WebServlet(value = "/manager/safe/deleteemp")
public class DeleteEmpController  extends HttpServlet {
    @Override
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {

        int id=Integer.valueOf(req.getParameter("id"));

        EmpService empService=new EmpServiceImpl();
        empService.delete(id);

        resp.sendRedirect(req.getContextPath()+"/manager/safe/showall");
    }


    @Override
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
        super.doPost(req, resp);
    }
}

三、项目效果图

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总结

1.这是小菜鸡学完web基础知识搭建的一个简单的web项目。
2.page封装的逻辑有点复杂，还需要计算，需要花点心思细细的去品。
3.web项目的相关路径可以不去web.x里面去配置，这样比较麻烦。可以直接在servlet里面用注释@webServlet（）。
4.遇到报错不要慌张，要慢慢的去查，去改正。以后遇到这种bug就能轻松的解决了。
5.小菜鸡的第一次发表，希望大家多多支持，如果有错误的地方，希望大家能够指出交流，蟹蟹！

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