java自学笔记（day19）归纳总结自：B站狂神说java

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整合SSM

1、环境要求

1.1、配置环境

使用工具：

IDEA 2020.1
MySQL 8.0.18
Tomcat 9
Maven 3.6.3

要求：

需要熟练掌握MySQL数据库，Spring，JavaWeb及MyBatis知识，简单的前端知识

1.2、数据库环境：

创建一个存放书籍数据的数据库表

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 '描述',
  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');

1.3、基本环境搭建

1、新建一Maven项目！ssmbuild，添加web的支持

2、导入相关的pom依赖！

<!--依赖：junit，数据库驱动，连接池，servlet，jsp，mybatis，mybatis-spring，spring，lombok-->

<dependencies>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>3.8.2</version>
    </dependency>
    <!-- https://mvnrepository.com/artifact/mysql/mysql-connector-java -->
    <dependency>
        <groupId>mysql</groupId>
        <artifactId>mysql-connector-java</artifactId>
        <version>8.0.18</version>
    </dependency>
    <dependency>
        <groupId>com.mchange</groupId>
        <artifactId>c3p0</artifactId>
        <version>0.9.5.2</version>
        <type>jar</type>
        <scope>compile</scope>
    </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>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis</artifactId>
        <version>3.5.2</version>
    </dependency>
    <dependency>
        <groupId>org.mybatis</groupId>
        <artifactId>mybatis-spring</artifactId>
        <version>2.0.6</version>
    </dependency>

    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-webmvc</artifactId>
        <version>5.3.3</version>
    </dependency>
    <dependency>
        <groupId>org.springframework</groupId>
        <artifactId>spring-jdbc</artifactId>
        <version>5.3.3</version>
    </dependency>

    <!-- https://mvnrepository.com/artifact/org.projectlombok/lombok -->
    <dependency>
        <groupId>org.projectlombok</groupId>
        <artifactId>lombok</artifactId>
        <version>1.18.12</version>
        <scope>provided</scope>
    </dependency>
    <dependency>
        <groupId>junit</groupId>
        <artifactId>junit</artifactId>
        <version>RELEASE</version>
        <scope>test</scope>
    </dependency>

</dependencies>

3、Maven资源过滤设置

<!--静态资源导出问题-->
<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>

4、建立基本结构和配置框架！

com.kuang.pojo
com.kuang.dao
com.kuang.service
com.kuang.controller

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>

</configuration>

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">


</beans>

2、Mybatis层

1、数据库配置文件 database.properties

jdbc.driver=com.mysql.cj.jdbc.Driver
jdbc.url=jdbc:mysql://localhost:3306/ssmbuild?useSSL=true&useUnicode=true&characterEncoding=utf8&serverTimezone=Asia/Shanghai
jdbc.username=root
jdbc.password=123456

2、IDEA关联数据库

3、编写MyBatis的核心配置文件

<?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核心配置文件-->
<configuration>

    <!--配置数据源，交给Spring去做-->

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

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

</configuration>

4、编写数据库对应的实体类 com.kuang.pojo.Books

使用lombok插件！

package com.kuang.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;
    
}

5、编写Dao层的Mapper接口！

package com.sun.dao;

import com.sun.pojo.Books;
import org.apache.ibatis.annotations.Param;
import org.springframework.web.bind.annotation.PathVariable;

import java.util.List;

public interface BookMapper {

    //增加一本书
    int addBook(Books books);

    //删除一本书
    int deleteBookById(@Param("bookId") int id);

    //更新一本书
    int updateBook(Books books);

    //查询一本书
    Books queryBookById(@Param("bookId") int id);

    //查询全部的书
    List<Books> queryAllBook();


    //搜索书籍
    Books queryBookByName(@PathVariable("bookName") String bookName);

}

6、编写接口对应的 Mapper.xml 文件，需要导入MyBatis的包

<?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.sun.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" resultType="Books">
        select * from ssmbuild.books
        where bookID = #{bookId};
    </select>

    <select id="queryAllBook" resultType="Books">
        select * from ssmbuild.books;
    </select>

    <select id="queryBookByName" resultType="Books">
        select * from ssmbuild.books where bookName = #{bookName};
    </select>

</mapper>

7、编写Service层的接口和实现类

接口：

package com.sun.service;

import com.sun.pojo.Books;

import java.util.List;

public interface BookService {

    //增加一本书
    int addBook(Books books);

    //删除一本书
    int deleteBookById(int id);

    //更新一本书
    int updateBook(Books books);

    //查询一本书
    Books queryBookById(int id);

    //查询全部的书
    List<Books> queryAllBook();

    //搜索书籍
    Books queryBookByName(String bookName);
}

实现类：

package com.sun.service;

import com.sun.dao.BookMapper;
import com.sun.pojo.Books;

import java.util.List;

public class BookServiceImpl implements BookService{

    //service层调用dao层： 组合Dao
    private BookMapper bookMapper;

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

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

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

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

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

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

    public Books queryBookByName(String bookName) {
        return bookMapper.queryBookByName(bookName);
    }
}

OK，到此，底层需求操作编写完毕！

3、Spring层

1、配置Spring整合MyBatis，我们这里数据源使用c3p0连接池；

2、我们去编写Spring整合Mybatis的相关的配置文件

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 https://www.springframework.org/schema/context/spring-context.xsd">


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

    <!--2.连接池
        dbcp: 半自动化操作，不能自动连接
        c3p0: 自动化操作(自动化地加载配置文件，并且可以自动设置到对象中！)
        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连接池的私有属性-->
        <property name="maxPoolSize" value="30"/>
        <property name="minPoolSize" value="10"/>
        <!--关闭连接后不自动commit-->
        <property name="autoCommitOnClose" value="false"/>
        <!--获取连接超时时间-->
        <property name="checkoutTimeout" value="10000"/>
        <!--当获取连接失败重试次数-->
        <property name="acquireRetryAttempts" value="2"/>
    </bean>


    <!--3.sqlSessionFactory-->
    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
        <property name="dataSource" ref="dataSource"/>
        <!--绑定Mybatis的配置文件-->
        <property name="configLocation" value="classpath:mybatis-config.xml"/>
    </bean>

    <!--4.配置dao接口扫描包，动态地实现了Dao接口可以注入到Spring容器中！-->
    <bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
        <!--注入sqlSessionFactory-->
        <property name="sqlSessionFactoryBeanName" value="sqlSessionFactory"/>
        <!--要扫描的包-->
        <property name="basePackage" value="com.sun.dao"/>
    </bean>


</beans>

spring-service.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 https://www.springframework.org/schema/context/spring-context.xsd">

    <!--1.扫描service下的包-->
    <context:component-scan base-package="com.sun.service"/>

    <!--2.将我们的所有业务类，注入到Spring，可以通过配置，或者注解实现-->
    <bean id="BookServiceImpl" class="com.sun.service.BookServiceImpl">
        <property name="bookMapper" ref="bookMapper"/>
    </bean>

    <!--3.声明事务配置-->
    <bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
        <!--4.注入数据源-->
        <property name="dataSource" ref="dataSource"/>
    </bean>

    <!--4.aop事务支持！-->

</beans>

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">

    <!--1.DispatcherServlet-->
    <servlet>
        <servlet-name>SpringMVC</servlet-name>
        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
        <init-param>
            <param-name>contextConfigLocation</param-name>
            <!--一定要注意:我们这里加载的是总的配置文件！-->
            <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>


    <!--2.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>

    <!--3.Session过期时间-->
    <session-config>
        <session-timeout>15</session-timeout>
    </session-config>

</web-app>

2、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 https://www.springframework.org/schema/mvc/spring-mvc.xsd http://www.springframework.org/schema/context https://www.springframework.org/schema/context/spring-context.xsd">

    <!--1.注解驱动-->
    <mvc:annotation-driven/>

    <!--2.静态资源过滤-->
    <mvc:default-servlet-handler/>

    <!--3.扫描包：controller-->
    <context:component-scan base-package="com.sun.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>

3、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">

    <import resource="classpath:spring-dao.xml"/>
    <import resource="classpath:spring-service.xml"/>
    <import resource="classpath:spring-mvc.xml"/>

</beans>

配置文件，暂时结束！下面Controller和视图层编写

5、Controller类

BookController

package com.sun.controller;

import com.sun.pojo.Books;
import com.sun.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.ArrayList;
import java.util.List;

@Controller
@RequestMapping("/book")
public class BookController {

    //controller 调用 service

    @Autowired
    @Qualifier("BookServiceImpl")
    private BookService bookService;

    //查询全部的书籍，并且返回到一个书籍展示页面
    @RequestMapping("/allBook")
    public String list(Model model) {
        List<Books> list = bookService.queryAllBook();

        model.addAttribute("list", list);

        return "allBook";
    }

    //跳转到增加书籍页面
    @RequestMapping("/toAddPaper")
    public String toAddPaper() {
        return "addBook";
    }

    //添加书籍的请求
    @RequestMapping("/addBook")
    public String addBook(Books books) {
        System.out.println("addBook=>"+books);
        bookService.addBook(books);
        return "redirect:/book/allBook";  //重定向到我们的@RequestMapping("/allBook")请求;
    }


    //跳转到修改页面
    @RequestMapping("/toUpdate")
    public String toUpdatePaper(int id, Model model) {
        Books books = bookService.queryBookById(id);
        model.addAttribute("QBook", books);
        return "updateBook";
    }

    //修改书籍
    @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}")
    public String deleteBook(@PathVariable("bookId") int id) {
        bookService.deleteBookById(id);
        return "redirect:/book/allBook";
    }

    //搜索书籍
    @RequestMapping("/queryBook")
    public String queryBook(String queryBookName, Model model) {
        Books books = bookService.queryBookByName(queryBookName);
        List<Books> list = new ArrayList<Books>();
        list.add(books);

        if (books == null) {
            list = bookService.queryAllBook();
            model.addAttribute("error", "未查到");
        }

        model.addAttribute("list", list);
        return "allBook";
    }

}

6、视图层

index.jsp

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

    <style>
      a{
        text-decoration: none;
        color: black;
        font-size: 18px;
      }
      h3{
        width: 180px;
        height: 38px;
        margin: 250px auto;
        text-align: center;
        line-height: 38px;
        background: deepskyblue;
        border-radius: 5px;
      }

    </style>

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

在这里插入图片描述

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>书籍展示</title>

    <%--BootStrap美化界面--%>
    <link href="https://cdn.staticfile.org/twitter-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>

            <div class="row">
                <div class="col-md-4 column">
                    <%--toAddBook--%>
                    <a class="btn btn-primary" href="${pageContext.request.contextPath}/book/toAddPaper">新增书籍</a>
                    <a class="btn btn-primary" href="${pageContext.request.contextPath}/book/allBook">显示全部书籍</a>
                </div>
                <div class="col-md-8 column">
                    <%--搜索书籍--%>
                    <form class="form-inline" action="${pageContext.request.contextPath}/book/queryBook" method="post" style="float: right">
                        <span style="color: red; font-weight: bold">${error}</span>
                        <input type="text" name="queryBookName" class="form-control" placeholder="请输出要查询的书籍名称">
                        <input type="submit" value="查询" class="btn btn-primary">
                    </form>
                </div>
            </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>

                    <%--书籍从数据库中查询出来，从这个list中遍历出来：foreach--%>
                    <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=${book.bookID}">修改</a>
                                    &nbsp; | &nbsp;
                                    <a href="${pageContext.request.contextPath}/book/deleteBook/${book.bookID}">删除</a>
                                </td>
                            </tr>
                        </c:forEach>
                    </tbody>

                </table>
            </div>
        </div>

    </div>


</body>
</html>

在这里插入图片描述

addBook.jsp

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

    <%--BootStrap美化界面--%>
    <link href="https://cdn.staticfile.org/twitter-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>


        <form action="${pageContext.request.contextPath}/book/addBook" method="post">
            <div class="form-group">
                <label>书籍名称：</label>
                <input type="text" name="bookName" class="form-control" required>
            </div>
            <div class="form-group">
                <label>书籍数量：</label>
                <input type="text" name="bookCounts" class="form-control" required>
            </div>
            <div class="form-group">
                <label>书籍描述：</label>
                <input type="text" name="detail" class="form-control" required>
            </div>
            <div class="form-group">
                <input type="submit" class="form-control" value="添加">
            </div>
        </form>

    </div>


</body>
</html>

在这里插入图片描述

updateBook.jsp

<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head>
    <title>修改书籍</title>
    <%--BootStrap美化界面--%>
    <link href="https://cdn.staticfile.org/twitter-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>修改书籍</small>
                </h1>
            </div>
        </div>
    </div>


    <form action="${pageContext.request.contextPath}/book/updateBook" method="post">

        <%--出现的问题：我们提交了修改的SQL请求，但是修改失败，初次考虑是事务的问题，配置完毕事务，依旧失败
        看一下sql语句，能否正常执行，sql执行失败，修改为完成，因为没有传递id
        --%>

        <%--前端传递隐藏域!!!!--%>

        <input type="hidden" name="bookID" value="${QBook.bookID}">

        <div class="form-group">
            <label>书籍名称：</label>
            <input type="text" name="bookName" class="form-control" value="${QBook.bookName}" required>
        </div>
        <div class="form-group">
            <label>书籍数量：</label>
            <input type="text" name="bookCounts" class="form-control" value="${QBook.bookCounts}" required>
        </div>
        <div class="form-group">
            <label>书籍描述：</label>
            <input type="text" name="detail" class="form-control" value="${QBook.detail}" required>
        </div>
        <div class="form-group">
            <input type="submit" class="form-control" value="修改">
        </div>
    </form>

</div>


</body>
</html>

在这里插入图片描述

7、个人小结

7.1、ssm整合流程

导包
连接mysql
建包，pojo、controller、service、dao
在resources下建xml,mybatis-config.xml和application.xml(建立Spring，后面的直接添加进去)
在resources下写数据库配置文件，database.properties
在pojo中新建Books实体类，并在mybatis-config.xml中给pojo起别名
在dao层写增删改查的接口BookMapper，在写BookMapper.xml去写增删改查语句的实现,最后把BookMapper.xml注册到mybatis-config.xml中
在service层写BookService接口(同样是增删改查),再写BookServiceImpl去实现接口，在BookServiceImpl需要利用set方法调用dao层
新建spring-dao.xml，并添加至ApplicationContext中
1. 关联数据库配置文件
2. 连接池
3. sqlSessionFactory
4. 配置dao接口扫描包，动态地实现了Dao接口可以注入到Spring容器中！
新建spring-service.xml，并添加至ApplicationContext中
1. 扫描service下的包
2. 将我们的所有业务类，注入到Spring，可以通过配置，或者注解实现
3. 声明事务配置
4. aop事务支持！
添加web application支持
配置web.xml
1. DispatcherServlet
2. 乱码过滤
3. Session过期时间
在resources中新建spring-mvc.xml，并添加至ApplicationContext中
1. 注解驱动
2. 静态资源过滤
3. 扫描包：controller
4. 视图解析器
在WEB-INF下新建jsp文件夹
开始写Controller+jsp页面

7.2、排错经验

问题1： bean不存在

步骤：

查看这个bean注入是否成功 ok
Junit单元测试，看我们的代码是否能够查询出来结果！ ok
问题，一定不在我们的底层，是Spring出了问题！
SpringMVC，整合的时候没调用我们的service层的bean；
1.applicationContext.xml 没有注入bean
2.web.xml中，我们也绑定过配置文件！发现问题：我们配置的Spring-mvc.xml
这里面确实没有 service bean，所以报空指针！

问题2：Method com/mchange/v2/c3p0/impl/NewProxyResultSet.isClosed()Z is abstract
把c3p0的jar包更新一下，并把out文件夹中的原来的jar包删掉

<dependency>
    <groupId>com.mchange</groupId>
    <artifactId>c3p0</artifactId>
    <version>0.9.5.2</version>
    <type>jar</type>
    <scope>compile</scope>
</dependency>

问题3：无法正常修改数据，且事务自动提交已开启
原因：update语句中需要根据id来进行修改，但是传参的时候没有给出。所以，采用隐藏域获得bookID

<input type="hidden" name="bookID" value="${QBook.bookID}">

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Java教程

java自学笔记（day19）归纳总结自：B站狂神说java

整合SSM

1、环境要求

1.1、配置环境

1.2、数据库环境：

1.3、基本环境搭建

2、Mybatis层

3、Spring层

4、SpringMVC层

5、Controller类

6、视图层

7、个人小结

7.1、ssm整合流程

7.2、排错经验

前端开发

后端开发

移动端开发

数据库

服务器运维

人工智能

区块链

游戏开发

网站运营

大数据/云计算

软件工程

软件/开发工具使用

资讯