SpringMVC：SpringMVC+mybatis实现基本操作

SpringMVC第一次课：第一次

对于SpringMVC 有了一个基本的认识。

导入SpringMVC+mybatis的依赖

spring-webmvc：springmvc核心依赖

<dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>4.3.10.RELEASE</version>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>4.0.1</version>
            <scope>provided</scope>
        </dependency>


        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.4.1</version>
        </dependency>

        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.43</version>
        </dependency>

        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
            <scope>runtime</scope>
        </dependency>
        
        <dependency>
            <groupId>taglibs</groupId>
            <artifactId>standard</artifactId>
            <version>1.1.2</version>
        </dependency>

导入C标签！：jstl、standard，C标签的基本库和方法库

web.xml:

<!DOCTYPE web-app PUBLIC
        "-//Sun Microsystems, Inc.//DTD Web Application 2.3//EN"
        "http://java.sun.com/dtd/web-app_2_3.dtd" >

<web-app>
    <display-name>Archetype Created Web Application</display-name>

    <filter>
        <filter-name>characterEncodingFilter</filter-name>
        <filter-class>org.springframework.web.filter.CharacterEncodingFilter</filter-class>
        <init-param>
            <param-name>encoding</param-name>
            <param-value>UTF-8</param-value>
        </init-param>
        <init-param>
            <param-name>forceEncoding</param-name>
            <param-value>true</param-value>
        </init-param>
    </filter>
    <filter-mapping>
        <filter-name>characterEncodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <servlet>
        <servlet-name>springmvc</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <param-value>classpath:springmvc.xml</param-value>
        </init-param>
    </servlet>

    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>*.action</url-pattern>
    </servlet-mapping>

    <welcome-file-list>
        <welcome-file>/students.action</welcome-file>
    </welcome-file-list>

</web-app>

配置乱码过滤器characterEncodingFilter

DispatcherServlet：springmvc入口servlet

welcome-file：首页

实体类：

具体封装alt+insert

 private int stuId;
    private String stuName;
    private String stuSex;
    private int stuAge;

student映射Mapper：实现操作的SQL

cache：二级缓存

concat：拼接模糊查询的SQL

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapper
        PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-mapper.dtd">

<mapper namespace="com.hc.dao.StudentDao">

    <cache></cache>

    <select id="likeStudent" resultType="Student">
        select * from student
        <where>
            <if test="likeStr!=null">
                stuName like concat('%',#{likeStr},'%') or
                stuSex like concat('%',#{likeStr},'%') or
                stuAge like concat('%',#{likeStr},'%')
            </if>
        </where>

    </select>


    <select id="selectStudent" resultType="Student" parameterType="int">
        select * from student where stuId=#{stuid}
    </select>


    <select id="allStudent" resultType="Student">
        select * from student
    </select>

    <update id="updateStudent" parameterType="Student">
        update student
        <set>
            <trim suffixOverrides=",">
                <if test="stuName!=null">
                    stuName=#{stuName},
                </if>
                <if test="stuSex!=null">
                    stuSex=#{stuSex},
                </if>
                <if test="stuAge!=null and stuAge!=0">
                    stuAge=#{stuAge},
                </if>
            </trim>
        </set>
        <if test="stuId!=null">
            where stuId=#{stuId}
        </if>
    </update>


    <delete id="deleteStudent">
        delete from student where stuId=#{stuid}
    </delete>


    <sql id="keys">
        <trim suffixOverrides=",">
            <if test="stuName!=null">
                stuName,
            </if>
            <if test="stuSex!=null">
                stuSex,
            </if>
            <if test="stuAge!=null and stuAge!=0">
                stuAge,
            </if>
        </trim>
    </sql>

    <sql id="values">
        <trim suffixOverrides=",">
            <if test="stuName!=null">
                #{stuName},
            </if>
            <if test="stuSex!=null">
                #{stuSex},
            </if>
            <if test="stuAge!=null and stuAge!=0">
                #{stuAge},
            </if>
        </trim>
    </sql>

    <insert id="insertStudent" parameterType="Student">
        insert into student(<include refid="keys"></include>) values(<include refid="values"></include>)
    </insert>

</mapper>

student的mapper会被sqlsession借助dao的接口调用

dao接口：

动态sql的模糊查需要Map

package com.hc.dao;

import com.hc.entity.Student;
import java.util.List;
import java.util.Map;

public interface StudentDao {

    public void insertStudent(Student student);
    public void deleteStudent(int stuId);
    public void updateStudent(Student student);

    public Student selectStudent(int stuId);
    public List<Student> likeStudent(Map<String,Object> map);
    public List<Student> allStudent();
}

dao的实现类

定义factory ，加载mybatis配置，myBatis-config加载具体的对象Mapper

session通过factory 打开

dao被session实例化

日后的诸如此类的加载对象，将会通过spring工厂产生

package com.hc.dao;

import com.hc.entity.Student;
import org.apache.ibatis.session.SqlSession;
import org.apache.ibatis.session.SqlSessionFactory;
import org.apache.ibatis.session.SqlSessionFactoryBuilder;


import java.util.HashMap;
import java.util.List;
import java.util.Map;

public class StudentImpl {

    SqlSessionFactory factory = new SqlSessionFactoryBuilder().build(getClass().getClassLoader().getResourceAsStream("myBatis-config.xml"));
    SqlSession session = factory.openSession();
    StudentDao studentDao = session.getMapper(StudentDao.class);

    public List<Student> allStudent() {
        List<Student> studentList=studentDao.allStudent();
        session.close();
        return studentList;
    }

    public List<Student> likeStudent(String likeStr) {
//      string：  if 判断 需要map 无需指明传入的参及参的类型
        Map<String,Object> map=new HashMap<>();
        map.put("likeStr",likeStr);
        List<Student> studentList=studentDao.likeStudent(map);
        session.close();
        return studentList;
    }

    public Student selectStudent(int stuId) {
        Student student= studentDao.selectStudent(stuId);
        session.close();
        return student;
    }


    public void insertStudent(Student student) {
         studentDao.insertStudent(student);
         session.commit();
         session.close();
    }
    public void deleteStudent(int stuId) {
        studentDao.deleteStudent(stuId);
        session.commit();
        session.close();
    }
    public void updateStudent(Student student) {
        studentDao.updateStudent(student);
        session.commit();
        session.close();
    }
}

封装各个方法，以便 controller 使用

controller:

在类之上，进行controller的注解

方法：RequestMapping ，括号内的是访问路径，只有这个访问路径被允许调用这个方法

package com.hc.controller;

import com.hc.dao.StudentImpl;
import com.hc.entity.Student;
import org.springframework.stereotype.Controller;
import org.springframework.web.bind.annotation.RequestMapping;
import org.springframework.web.bind.annotation.RequestParam;

import javax.servlet.http.HttpServletRequest;
import java.util.Map;

@Controller
public class StudentController {

    @RequestMapping("/students")
    public String allStudent(HttpServletRequest request){
        request.setAttribute("students",new StudentImpl().allStudent());
        return "success";
    }

    @RequestMapping("/likeStudent")
    public String likeStudent(@RequestParam("likeStr") String likeStr, HttpServletRequest request){
        request.setAttribute("students",new StudentImpl().likeStudent(likeStr));
        return "success";
    }

    @RequestMapping("/insertStudent")
    public String insertStudent(Student student){
        new StudentImpl().insertStudent(student);
        return "redirect:students.action";
    }

    @RequestMapping("/deleteStudent")
    public String deleteStudent(int stuId){
        new StudentImpl().deleteStudent(stuId);
        return "redirect:students.action";
    }

    @RequestMapping("/updateStudent")
    public String updateStudent(Student student){
        new StudentImpl().updateStudent(student);
        return "redirect:students.action";
    }

    @RequestMapping("/selectStudent")
    public String selectStudent(int stuId, Map map){
        map.put("student",new StudentImpl().selectStudent(stuId));
        return "first";
    }
}

redirect：转发，一个方法调另一个方法

数据展示页面：

导入C标签

<%--
  Created by IntelliJ IDEA.
  User: admin
  Date: 2018/11/2
  Time: 19:57
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" isELIgnored="false" language="java" %>
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<a href="/students.action">students</a>
<a href="/insert.jsp">insert</a>

<div align="center">

    <form action="/likeStudent.action" method="post">

        <input type="text" name="likeStr">
        <input type="submit" value="搜索">
    </form>


<table border="1" width="600">

    <tr align="center">
        <td>编号</td>
        <td>姓名</td>
        <td>性别</td>
        <td>年龄</td>
        <td>销户</td>
        <td>资料</td>
    </tr>
    <c:forEach items="${students}" var="student">

        <tr align="center">
            <td>${student.stuId}</td>
            <td>${student.stuName}</td>
            <td>${student.stuSex}</td>
            <td>${student.stuAge}</td>
            <td><a href="/deleteStudent.action?stuId=${student.stuId}" onclick="return confirm('是否删除？')">删除</a></td>
            <td><a href="/selectStudent.action?stuId=${student.stuId}">修改</a></td>
        </tr>
    </c:forEach>


</table>
</div>


</body>
</html>

C:foreach：可循环list，items是传过来的list，var代表的是一个对象

${ }:EL表达式

注意：EL一定要在最上方声明： isELIgnored="false"

insert：

普通的表单，输入框的name一定要与对象的属性名一致，否则，无法自动收集

<%--
  Created by IntelliJ IDEA.
  User: admin
  Date: 2018/11/2
  Time: 17:19
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" isELIgnored="false" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<div align="center">
<form action="/insertStudent.action" method="post">
    名字：<input type="text" name="stuName"><br><br>
    性别：<input type="text" name="stuSex"><br><br>
    年龄：<input type="text" name="stuAge"><br><br>
    <input type="submit" value="新增">
</form>
</div>
</body>
</html>

align="center"：居中

update：

<%--
  Created by IntelliJ IDEA.
  User: admin
  Date: 2018/11/2
  Time: 17:19
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" isELIgnored="false" language="java" %>
<html>
<head>
    <title>Title</title>
</head>
<body>

<div align="center">
<form action="/updateStudent.action" method="post">
     <input type="hidden" value="${student.stuId}" name="stuId">
    名字： <input type="text" value="${student.stuName}" name="stuName"><br><br>
    性别： <input type="text" value="${student.stuSex}" name="stuSex"><br><br>
    年龄： <input type="text" value="${student.stuAge}" name="stuAge"><br><br>
    <input type="submit" value="欧克">
</form>
</div>
</body>
</html>

传过来的是一个对象，无需C标签，直接EL表达式即可

Springmvc.xml配置

mybatis-config.xml见上期

初步整合！

if 再加上Spring，就是SSM！

SpringMVC：SpringMVC+mybatis实现基本操作

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