一、mybatis层
1、搭建数据库:
//创建数据库
CREATE DATABASE `ssmbuild`; //选择数据库
USE `ssmbuild`//检查如果数据库中有books这个表的话就给他删除
DROP TABLE IF EXISTS `books`//创建表books
CREATE TABLE `books`(
`bookID` INT(10) NOT NULL AUTO_INCREMENT COMMENT '图书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`)
)//插入数据
INSERT INTO `books` 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');
2、搭建maven项目
创建之后的目录:
在配置文件中导入需要用到的依赖
<!--需要的相关依赖--><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></dependencies>
maven资源过滤设置
<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>
3、连接数据库
4、创建包结构和配置文件结构(目前够用的)
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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsd">
</beans>
mybatis-config.xml
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
</configuration>
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=root
下面完成mybatis-config.xml的配置
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!--数据源交给spring去做了,这里我们主要做取别名和映射一些mappers配置文件--><!--给pojo包下的所有类取别名--><typeAliases><package name="com.li.pojo"/></typeAliases><!--映射等一下来做-->
</configuration>
5、编写实体类(pojo)和接口(dao)
因为要偷懒,在maven中导入lombok的依赖
<!--lombok--><dependency><groupId>org.projectlombok</groupId><artifactId>lombok</artifactId><version>1.18.30</version></dependency>
编写实体类
@Data
@AllArgsConstructor
@NoArgsConstructor
public class Books {private int bookID;private String bookName;private int bookCounts;private String detail;}
编写接口
package com.li.dao;import com.li.pojo.Books;import java.util.List;public interface BookMapper {//增加一本书int addBook(Books books);//根据删除一本书int deleteBookByID(int id);//修改一本书int updateBook(Books books);//根据id查询一本书Books queryBookId(int id);//查询所有的书List<Books> queryAllBook();}
编写xxxMapper.xml文件执行sql语句
头文件直接用mybatis-config.xml的改
修改后:
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper></mapper>
编写sql语句
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE mapperPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.li.dao.BookMapper"><insert id="addBook" parameterType="books" >insert into ssmbuild.books(bookName,bookCounts,detail)values (#{bookName},#{bookCounts},#{detail},);</insert><delete id="deleteBookByID" parameterType="int">deletefrom ssmbuild.bookswhere bookID = #{bookID};</delete><update id="updateBook" parameterType="books">update ssmbuild.booksset bookName = #{books},bookCounts = #{bookCounts},detail = #{detail}where bookID = #{bookID};</update><select id="queryBookId" resultType="books" parameterType="int">select *from ssmbuild.bookswhere bookID = #{bookID};</select><select id="queryAllBook" resultType="books">select *from ssmbuild.books;</select>
</mapper>
写完sql语句后第一件事就是将xxxMapper.xml配置文件绑定到mybatis的配置文件中,两种绑定(映射)方式
<?xml version="1.0" encoding="UTF-8" ?>
<!DOCTYPE configurationPUBLIC "-//mybatis.org//DTD Config 3.0//EN""http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<!--数据源交给spring去做了,这里我们主要做取别名和映射一些mappers配置文件--><!--给pojo包下的所有类取别名--><typeAliases><package name="com.li.pojo"/></typeAliases><!--映射等一下来做--><mappers><mapper resource="com/li/dao/BookMapper.xml"/></mappers><!-- <mappers>-->
<!-- <mapper class="com.li.dao.BookMapper"/>-->
<!-- </mappers>--></configuration>
6、编写业务层(service)
package com.li.service;import com.li.dao.BookMapper;
import com.li.pojo.Books;import java.util.List;public class BookServiceImp implements BookService{//service调dao层, 组合daoprivate BookMapper bookMapper;public void setBookMapper(BookMapper bookMapper) {this.bookMapper = bookMapper;}//增加一本书public int addBook(Books books){return bookMapper.addBook(books);}//根据删除一本书public int deleteBookByID(int id){return bookMapper.deleteBookByID(id);}//修改一本书public int updateBook(Books books){return bookMapper.updateBook(books);}//根据id查询一本书public Books queryBookId(int id){return bookMapper.queryBookId(id);}//查询所有的书public List<Books> queryAllBook(){return bookMapper.queryAllBook();}}
到这里mybatis层就基本的就写的差不多了
二、Spring层
编写spring整合dao层的配置文件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/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttps://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 c3p0(这里用这个连接池,用之前需要先导入包,我们之前已经导入过了) druid hikari
--><bean id="dataSource" class="com.mchange.v2.c3p0.ComboPooledDataSource"><!--配置连接池属性--><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.xlm"/></bean><!--4、配置dao接口扫描包,动态的实现了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"/>
<!-- 需要扫描的dao包--><property name="basePackage" value="com.li.dao"/></bean></beans>
三、整合service层
编写spring整合service层的配置文件spring-service.xml
在注入所有的业务类时要将三个配置文件 spring-service.xml applicationContext.xml spring-dao.xml三个配置文件整合到一起
要不然会报错如下:
使用注解将所有业务类注入到Spring中
spring-service.xml配置文件
<?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/beanshttp://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.li.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 这里用配置--><bean id="BookServiceImp" class="com.li.service.BookServiceImp"><property name="bookMapper" ref="bookMapper"/></bean><!--3.申明式事务配置--><bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
<!--注入数据源 --><property name="dataSource" ref="dataSource"/></bean></beans>
四、springmvc层
1、配置web.xml配置文件
<?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.注册DispatcherServlet--><servlet><servlet-name>springmvc</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><!--关联一个springmvc的配置文件:【servlet-name】-servlet.xml--><init-param><param-name>contextConfigLocation</param-name><param-value>classpath:spring-mvc.xml</param-value></init-param><!--启动级别-1--><load-on-startup>1</load-on-startup></servlet><!--/ 匹配所有的请求;(不包括.jsp)--><!--/* 匹配所有的请求;(包括.jsp)--><servlet-mapping><servlet-name>springmvc</servlet-name><url-pattern>/</url-pattern></servlet-mapping>
</web-app>
编写spring-mvc.xml配置文件
<?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"xmlns:mvc="http://www.springframework.org/schema/mvc"xsi:schemaLocation="http://www.springframework.org/schema/beanshttp://www.springframework.org/schema/beans/spring-beans.xsdhttp://www.springframework.org/schema/contexthttps://www.springframework.org/schema/context/spring-context.xsdhttp://www.springframework.org/schema/mvchttps://www.springframework.org/schema/mvc/spring-mvc.xsd"><!-- 自动扫描包,让指定包下的注解生效,由IOC容器统一管理 --><context:component-scan base-package="com.li.controller"/><!-- 让Spring MVC不处理静态资源(静态资源过滤) --><mvc:default-servlet-handler /><!--支持mvc注解驱动在spring中一般采用@RequestMapping注解来完成映射关系要想使@RequestMapping注解生效必须向上下文中注册DefaultAnnotationHandlerMapping和一个AnnotationMethodHandlerAdapter实例这两个实例分别在类级别和方法级别处理。而annotation-driven配置帮助我们自动完成上述两个实例的注入。--><mvc:annotation-driven /><!-- 视图解析器 --><bean class="org.springframework.web.servlet.view.InternalResourceViewResolver"id="internalResourceViewResolver"><!-- 前缀 --><property name="prefix" value="/WEB-INF/jsp/" /><!-- 后缀 --><property name="suffix" value=".jsp" /></bean><!--这里是编写Controller类后注册的bean-->
<!-- <bean name="/h1" class="com.li.controller.ControllerTest1"/>-->
</beans>
到这里底层结构就差不多写完了
五、让Controller层和jsp交互起来
1、编写Controller类
package com.li.controller;import com.li.pojo.Books;
import com.li.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.PatchMapping;
import org.springframework.web.bind.annotation.RequestMapping;import java.util.List;@Controller
@RequestMapping("/book")
public class BookController {//Controller层调用 service层//为引用类型属性设置值@Autowired//为引用类型属性指定注入的bean@Qualifier("BookServiceImp")//设置全局变量private BookService bookService;//查询所有的书籍,并且返回到一个书籍展示页面@RequestMapping("/allBook")public String list(Model model){
// 调用查询全部书籍方法List<Books> books = bookService.queryAllBook();
// 将得到的值返回给前端model.addAttribute("books:",books);return "allBook";}}
2、编写返回的对应的前端页面和欢迎页跳转前端页面
首页跳转页面
<%@ taglib prefix="c" uri="http://java.sun.com/jsp/jstl/core" %>
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
<html>
<head><title>首页</title>
</head>
<body>
<h2><a href="${pageContext.request.contextPath}/book/allBook">进入书籍展示页面</a>
</h2>
</body>
</html>
前端页面
<%@ 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>
</head>
<body>
<h2>书籍展示</h2>
</body>
</html>
这里会报一个500的错
因为我们web.xml中关联spring配置文件的时候我们关联的是一部分配置文件,没有关联到总的配置文件
改成总配置文件就可以了
<?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.注册DispatcherServlet--><servlet><servlet-name>springmvc</servlet-name><servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class><!--关联一个springmvc的配置文件:【servlet-name】-servlet.xml--><init-param><param-name>contextConfigLocation</param-name><param-value>classpath:applicationContext.xml</param-value></init-param><!--启动级别-1--><load-on-startup>1</load-on-startup></servlet><!--/ 匹配所有的请求;(不包括.jsp)--><!--/* 匹配所有的请求;(包括.jsp)--><servlet-mapping><servlet-name>springmvc</servlet-name><url-pattern>/</url-pattern></servlet-mapping><!--解决乱码问题--><filter><filter-name>gen</filter-name><filter-class>com.li.properties.GenericEncodingFilter</filter-class></filter><filter-mapping><filter-name>gen</filter-name><url-pattern>/*</url-pattern></filter-mapping></web-app>
排错思路
3、从前端得到数据,和美化页面
1、写程序的顺序是 从底层出发最后到前端
数据库 ---》 dao层 ---》 service ---》 controller层 --->前端