关于后端:这个厉害了ssm框架整合全过程建议收藏起来好好看看

1.0 环境要求

• IDEA
• MySQL 5.7.19
• Tomcat 9
• Maven 3.6

1.1 数据库

创立书籍数据库表，包含书籍编号，书籍名称，书籍数量以及书籍形容。

CREATE DATABASE `ssmbuild`;
USE `ssmbuild`;
DROP TABLE IF EXISTS `books`;
CREATE TABLE `books` (`bookID` INT(10) NOT NULL AUTO_INCREMENT COMMENT '书 id',
`bookName` VARCHAR(100) NOT NULL COMMENT '书名',
`bookCounts` INT(11) NOT NULL COMMENT '数量',
`detail` VARCHAR(200) NOT NULL COMMENT '形容',
KEY `bookID` (`bookID`)
) ENGINE=INNODB DEFAULT CHARSET=utf8
INSERT INTO `books`(`bookID`,`bookName`,`bookCounts`,`detail`)VALUES
(1,'Java',1,'从入门到放弃'),
(2,'MySQL',10,'从删库到跑路'),
(3,'Linux',5,'从进门到进牢');

1.2 根本环境搭建

1. 新建一 Maven 我的项目！ssmbuild，增加 web 的反对
2. 导入相干的 pom 依赖和 maven 资源过滤

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.fanjh</groupId>
    <artifactId>ssmbuild</artifactId>
    <version>1.0-SNAPSHOT</version>

    <!-- 导入依赖 -->
    <dependencies>
        <!--Junit-->
        <dependency>
            <groupId>junit</groupId>
            <artifactId>junit</artifactId>
            <version>4.12</version>
        </dependency>

        <!-- 数据库驱动 -->
        <dependency>
            <groupId>mysql</groupId>
            <artifactId>mysql-connector-java</artifactId>
            <version>5.1.47</version>
        </dependency>

        <!-- 数据库连接池 -->
        <dependency>
            <groupId>com.mchange</groupId>
            <artifactId>c3p0</artifactId>
            <version>0.9.5.2</version>
        </dependency>

        <!--Servlet - JSP -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>servlet-api</artifactId>
            <version>2.5</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet.jsp</groupId>
            <artifactId>jsp-api</artifactId>
            <version>2.2</version>
        </dependency>
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>jstl</artifactId>
            <version>1.2</version>
        </dependency>

        <!--Mybatis-->
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis</artifactId>
            <version>3.5.2</version>
        </dependency>
        <dependency>
            <groupId>org.mybatis</groupId>
            <artifactId>mybatis-spring</artifactId>
            <version>2.0.2</version>
        </dependency>

        <!--Spring-->
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-webmvc</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.springframework</groupId>
            <artifactId>spring-jdbc</artifactId>
            <version>5.1.9.RELEASE</version>
        </dependency>
        <dependency>
            <groupId>org.projectlombok</groupId>
            <artifactId>lombok</artifactId>
            <version>1.18.12</version>
        </dependency>
    </dependencies>

    <!-- 动态资源过滤问题 -->
    <build>
        <resources>
            <resource>
                <directory>src/main/java</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
            <resource>
                <directory>src/main/resources</directory>
                <includes>
                    <include>**/*.properties</include>
                    <include>**/*.xml</include>
                </includes>
                <filtering>false</filtering>
            </resource>
        </resources>
    </build>
</project>

留神：这里导包之后记得查看 project structure 中有无相干包，个别要手动导入

1. 建设根本构造和框架：

• com.fanjh.pojo
• com.fanjh.dao
• com.fanjh.service
• com.fanjh.controller
• mybatis-config.xml

这里给出最终构造

前端调用 controller 层，controller 层调用 service 层，service 层调用 dao 层

1.2 mybatis 层编写

1. 数据库配置文件 database.properties

jdbc.driver=com.mysql.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/ssmbuild?useSSL=false&useUnicode=true&characterEncoding=utf8
jdbc.username=root
jdbc.password=fjhmysql

1. 连贯数据库
2. 编写 mybatis 外围配置文件：mybatis-config.xml

<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configuration
        PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
        "http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
    <!--mybatis 外围配置文件 -->
    <!-- 配置数据源等交给 spring 去做，这里次要别名和注册映射 -->

    <typeAliases>
        <package name="com.fanjh.pojo"/>
    </typeAliases>

    <mappers>
        <mapper class="com.fanjh.dao.BookMapper"/>
    </mappers>
</configuration>

1. 编写数据库对应实体类：com.fanjh.pojo.Books
   应用 lombok 插件

package com.fanjh.pojo;

import lombok.AllArgsConstructor;
import lombok.Data;
import lombok.NoArgsConstructor;

@Data
@AllArgsConstructor
@NoArgsConstructor
public class Books {
    private int bookID;
    private String bookName;
    private int bookCounts;
    private String detail;
}

1. 紧接着编写 dao 层的 mapper 接口

package com.fanjh.dao;

import com.fanjh.pojo.Books;
import org.apache.ibatis.annotations.Param;

import java.util.List;
// 增删改查办法
public interface BookMapper {int addBook(Books book);

    int deleteBookById(@Param("bookId") int id);

    int updateBook(Books book);

    Books queryBookById(@Param("bookId") int id);

    List<Books> queryAllBook();}

1. 马上编写接口对应的 Mapper.xml 文件（对应 sql 语句）, 须要注册到 mybatis.xml

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

<mapper namespace = "com.fanjh.dao.BookMapper">

    <insert id = "addBook" parameterType="Books">
        insert into ssmbuild.books(bookName, bookCounts, detail)
        VALUES(#{bookName}, #{bookCounts}, #{detail})
    </insert>

    <delete id="deleteBookById" parameterType="int">
        DELETE  from ssmbuild.books where bookID = #{bookId}
    </delete>

    <update id="updateBook" parameterType="Books">
        update ssmbuild.books
        set bookName=#{bookName}, bookCounts=#{bookCounts}, detail=#{detail}
        where bookID=#{bookID};
    </update>

    <select id="queryBookById" parameterType="int" resultType="Books">
        select * from ssmbuild.books where bookID=#{bookId};
    </select>

    <select id="queryAllBook" resultType="Books">
        select * FROM ssmbuild.books
    </select>
</mapper>

至此，搞定 dao 层，接下来业务层。

1. 编写 Service 层接口和实现类
   接口：

package com.fanjh.service;

import com.fanjh.pojo.Books;
import org.apache.ibatis.annotations.Param;
import java.util.List;

public interface BookService {int addBook(Books book);

    int deleteBookById(int id);

    int updateBook(Books book);

    Books queryBookById(int id);

    List<Books> queryAllBook();}

实现类：

package com.fanjh.service;

import com.fanjh.dao.BookMapper;
import com.fanjh.pojo.Books;
import java.util.List;

public class BookServiceImpl implements BookService {
    //service 层调 dao 层
    private BookMapper bookMapper;

    public void setBookMapper(BookMapper bookMapper) {this.bookMapper = bookMapper;}

    public int addBook(Books book) {return bookMapper.addBook(book);
    }

    public int deleteBookById(int id) {return bookMapper.deleteBookById(id);
    }

    public int updateBook(Books book) {return bookMapper.updateBook(book);
    }

    public Books queryBookById(int id) {return bookMapper.queryBookById(id);
    }

    public List<Books> queryAllBook() {return bookMapper.queryAllBook();
    }
}

能够看到，service 层的办法都是间接调用 dao 层的办法，到此底层需要操作编写结束。

1.3 spring 层

1. 配置 Spring 整合 MyBatis，这里应用 c3p0 连接池。
2. 编写Spring 整合 MyBatis 相干配置文件：spring-dao.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

    <!-- 配置整合 mybatis-->

    <!--1. 关联数据库文件 -->
    <context:property-placeholder location="classpath:database.properties"/>

    <!--2. 连接池：dbcp：半自动化操作，不能主动连贯
            c3p0：自动化操作（自动化的加载配置文件，并且能够主动设置到对象）druid、hikari-->
    <bean id="datasource" class="com.mchange.v2.c3p0.ComboPooledDataSource">
        <property name="driverClass" value="${jdbc.driver}"/>
        <property name="jdbcUrl" value="${jdbc.url}"/>
        <property name="user" value="${jdbc.username}"/>
        <property name="password" value="${jdbc.password}"/>

        <!--c3p0 连贯公有属性 -->
        <property name="maxPoolSize" value="30"/>
        <property name="minPoolSize" value="10"/>
        <!-- 敞开连贯后不主动 commit -->
        <property name="autoCommitOnClose" value="false"/>
        <!-- 获取连贯超时工夫 -->
        <property name="checkoutTimeout" value="10000"/>
        <!-- 当获取连贯失败重试次数 -->
        <property name="acquireRetryAttempts" value="2"/>
    </bean>

    <!--3.sqlsessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <!-- 注入数据库连接池 -->
        <property name="dataSource" ref="datasource"/>
        <!-- 配置 MyBaties 全局配置文件:mybatis-config.xml -->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
    </bean>

    <!--4. 配置 dao 接口扫描包，动静的实现了 Dao 接口能够注入到 spring 容器中 -->
    <!-- 以前要新建一个 dao 接口实现类，而后在 spring 中注册实现类 -->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!-- 注入 sqlsessionfactory 即可 -->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <!-- 要扫描的包 -->
        <property name="basePackage" value="com.fanjh.dao"/>
    </bean>
</beans>

1. spring 整合 service 层

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/context
        http://www.springframework.org/schema/context/spring-context.xsd">

    <!-- 如果下面配置错了，常会报错：通配符很全面，但无奈找到元素。。。的申明 -->

    <!--1. 扫描 service 包 -->
    <context:component-scan base-package="com.fanjh.service"/>

    <!--2. 将咱们所有的业务类，注入到 spring，能够通过配置或注解实现 @Service @Autowired-->
    <bean id="BookServiceImpl" class="com.fanjh.service.BookServiceImpl">
        <property name="bookMapper" ref="bookMapper"/>
    </bean>

    <!--3. 申明式事务管理期 -->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <!-- 注入数据库连接池 -->
        <property name="dataSource" ref="datasource"/>
    </bean>
</beans>

至此，spring 层搞定，spring 就是个大容器，整合 dao 层和 service 层，也是实现了 dao 层和 service 层的拆散——解耦。

1.4 springMVC 层

1. web.xml

<?xml version="1.0" encoding="UTF-8"?>
<web-app xmlns="http://xmlns.jcp.org/xml/ns/javaee"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://xmlns.jcp.org/xml/ns/javaee http://xmlns.jcp.org/xml/ns/javaee/web-app_4_0.xsd"
         version="4.0">

    <!--DispatchServlet-->
    <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:applicationContext.xml</param-value>
        </init-param>
        <load-on-startup>1</load-on-startup>
    </servlet>
    <servlet-mapping>
        <servlet-name>springmvc</servlet-name>
        <url-pattern>/</url-pattern>
    </servlet-mapping>

    <!-- 乱码过滤 -->
    <filter>
        <filter-name>encodingFilter</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>
    </filter>
    <filter-mapping>
        <filter-name>encodingFilter</filter-name>
        <url-pattern>/*</url-pattern>
    </filter-mapping>

    <!--session 过期工夫 -->
    <session-config>
        <session-timeout>15</session-timeout>
    </session-config>

</web-app>

1. spring-mvc.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:mvc="http://www.springframework.org/schema/mvc"
       xmlns:context="http://www.springframework.org/schema/context"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd
        http://www.springframework.org/schema/mvc
        http://www.springframework.org/schema/mvc/spring-mvc.xsd
        http://www.springframework.org/schema/context
        https://www.springframework.org/schema/context/spring-context.xsd">

    <!-- 配置映射器、适配器、视图解析器 -->

    <!--1. 注解驱动 -->
    <mvc:annotation-driven/>
    <!--2. 动态资源过滤 -->
    <mvc:default-servlet-handler/>
    <!--3. 扫描包 -->
    <context:component-scan base-package="com.fanjh.controller"/>
    <!--4. 视图解析器 -->
    <bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
        <property name="prefix" value="/WEB-INF/jsp/"/>
        <property name="suffix" value=".jsp"/>
    </bean>
</beans>

1. spring 配置整合文件：applicationContext.xml

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xsi:schemaLocation="http://www.springframework.org/schema/beans
        http://www.springframework.org/schema/beans/spring-beans.xsd">

    <!--spring 外围配置文件 -->
    <import resource="classpath:spring-dao.xml"/>
    <import resource="classpath:spring-service.xml"/>
    <import resource="classpath:spring-mvc.xml"/>

</beans>

至此，所有的配置文件暂告一段落，接下来编写 Controller 和视图层，Controller 和视图层交互，而后调用 service 层。

1. BookController 类编写，增删改查书籍（Controller 层的编写须要实时对照视图层）

package com.fanjh.controller;
import com.fanjh.pojo.Books;
import com.fanjh.service.BookService;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.beans.factory.annotation.Qualifier;
import org.springframework.stereotype.Controller;
import org.springframework.ui.Model;
import org.springframework.web.bind.annotation.PathVariable;
import org.springframework.web.bind.annotation.RequestMapping;
import java.util.List;

@Controller
@RequestMapping("/book")
public class BookController {
    @Autowired
    @Qualifier("BookServiceImpl")
    private BookService bookService;

    // 查问所有书籍，并且返回要给书籍展现页面
    @RequestMapping("/allBook")
    public String list(Model model) {List<Books> list = bookService.queryAllBook();
        model.addAttribute("list", list);
        return "allBook";
    }

    // 跳转到减少书籍页面
    @RequestMapping("/toAddBook")
    public String toAddBook(){return "addBook";}

    // 增加书籍的申请
    @RequestMapping("/addBook")// 执行完后，重定向到 allbook 页面
    public String addBook(Books books){System.out.println("addBook=>" + books);
        bookService.addBook(books);
        return "redirect:/book/allBook";
    }

    // 跳转到批改书籍页面
    @RequestMapping("/toUpdate")
    public String toUpdateBook(int id, Model model){Books books = bookService.queryBookById(id);// 依据 id 取到图书
        model.addAttribute("Qbooks",books);// 将图书返回给前端

        return "updateBook";
    }

    // 批改书籍
    // 接管到前端传来的数据，调用 service 层执行批改操作
    @RequestMapping("/updateBook")
    public String updateBook(Books books){System.out.println("updateBook=>" + books);
        bookService.updateBook(books);

        return "redirect:/book/allBook";
    }

    // 删除书籍
    @RequestMapping("/deleteBook/{bookId}")//restful 格调
    public String deleteBook(@PathVariable("bookId") int id){bookService.deleteBookById(id);

        return "redirect:/book/allBook";
    }
}

1. 编写首页index.jsp

<%--
  Created by IntelliJ IDEA.
  User: fjh990
  Date: 2020/11/7
  Time: 12:16
  To change this template use File | Settings | File Templates.
--%>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
  <title> 首页 </title>
  <style>
    a{
      text-decoration: none;
      color: gold;
      font-size: 50px;
    }
    h3{
      width:500px;
      height:80px;
      margin:500px auto;
      text-align: center;
      line-height: 80px;
      background: black;
      border-radius: 6px;
    }
  </style>
</head>
<body>

<h3>
  <a href="${pageContext.request.contextPath}/book/allBook"> 进入书籍页面 </a>
</h3>

</body>
</html>

1. 新建三个.jsp 文件：

• allBook：显示所有书籍
• addBook：减少书籍
• updateBook: 批改书籍

allBook.jsp:

<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title> 书籍展现 </title>

    <!-- 引入 Bootstrap -->
    <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>

<div class="container">
    <div class="row clearfix">
        <div class="col-md-12 column">
            <div class="page-header">
                <h1>
                    <small> 书籍列表——————显示所有书籍 </small>
                </h1>
            </div>
        </div>
        <%-- 减少书籍按钮, 点击后跳到 controller 页面，而后依据 return 值到 addbook.jsp--%>
        <div class="row">
            <div class="col-md-4 column">
                <a class="btn btn:primary" href="${pageContext.request.contextPath}/book/toAddBook"> 新增书籍 </a>
            </div>
        </div>

        <div class="row clearfix">
            <div class="col-md-12 column">
                <table class="table table-hover table-striped">
                    <thead>
                    <tr>
                        <th> 书籍编号 </th>
                        <th> 书籍名称 </th>
                        <th> 书籍数量 </th>
                        <th> 书籍详情 </th>
                        <th> 操作 </th>
                    </tr>
                    </thead>
                    <tbody>
                    <c:forEach var="book" items="${list}">
                        <tr>
                            <td>${book.bookID}</td>
                            <td>${book.bookName}</td>
                            <td>${book.bookCounts}</td>
                            <td>${book.detail}</td>
                            <td>
                                <a href="${pageContext.request.contextPath}/book/toUpdate?id=${book.bookID}"> 批改 </a>
                                &nbsp; | &nbsp;
                                <a href="${pageContext.request.contextPath}/book/deleteBook/${book.bookID}"> 删除 </a>
                            </td>
                        </tr>
                    </c:forEach>
                    </tbody>
                </table>
            </div>
        </div>
    </div>
</div>
</body>
</html>

addBook.jsp:

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title> 新增书籍 </title>

    <!-- 引入 Bootstrap -->
    <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>

<div class="container">
    <div class="row clearfix">
        <div class="col-md-12 column">
            <div class="page-header">
                <h1>
                    <small> 新增书籍 </small>
                </h1>
            </div>
        </div>
    </div>

    <%-- 点击增加按钮后，跳转到 /book/addBook 执行增加操作（属性名肯定要统一）--%>
    <form action="${pageContext.request.contextPath}/book/addBook"
          method="post">
        书籍名称：<input type="text" name="bookName" required><br><br><br>
        书籍数量：<input type="text" name="bookCounts" required><br><br><br>
        书籍详情：<input type="text" name="detail" required><br><br><br>
        <input type="submit" value="增加">
    </form>
</div>

</body>
</html>

这里拿减少书籍举例梳理整个流程：

1. 前端点击新增书籍按钮后，跳转到 controller 找到 /book/toAddBook，跳转到 toAddBook 页面
2. 依据 toAddBook 页面的 return 语句，拼接后找到 /WEB-INF/jsp/addBook.jsp 文件
3. 依据页面展现，填写所要减少的书籍的内容
4. 点击“增加”按钮，返回 controller 找到 /book/addBook 页面，并传回 books 信息
5. controller 层调用 service 层执行减少书籍操作。
6. 返回到显示书籍页面

updateBook.jsp:

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title> 批改书籍 </title>

    <!-- 引入 Bootstrap -->
    <link href="https://cdn.bootcss.com/bootstrap/3.3.7/css/bootstrap.min.css" rel="stylesheet">
</head>
<body>

<div class="container">
    <div class="row clearfix">
        <div class="col-md-12 column">
            <div class="page-header">
                <h1>
                    <small> 批改书籍 </small>
                </h1>
            </div>
        </div>

    </div>

    <%-- 咱们提交了批改的 sql 申请，然而批改失败，spring 接管事务后不须要显式的配置，不是事务问题
         看一下 sql 语句，是否执行胜利:sql 执行失败
         前端传递暗藏域 --%>

    <form action="${pageContext.request.contextPath}/book/updateBook"
          method="post">
        <input type="hidden" name="bookID" value="${Qbooks.bookID}">

        书籍名称：<input type="text" name="bookName" value="${Qbooks.bookName}" required><br><br><br>
        书籍数量：<input type="text" name="bookCounts" value="${Qbooks.bookCounts}" required><br><br><br>
        书籍详情：<input type="text" name="detail" value="${Qbooks.detail}" required><br><br><br>
        <input type="submit" value="批改">
    </form>
</div>

</body>
</html>

至此，整个我的项目整合结束

最初

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