SSM详细速成
ssm速成
此文对狂神说ssm整合 进行解读
mybatis 学习+测试
pojo.Books
@AllArgsConstructor
@NoArgsConstructor
@Data
public class Books {
private int bookId;
private String bookName;
private int bookCounts;
private String detail;
}
mybatis.xml核心文件
- 设置连接用户名密码
- 要访问的数据库名字
- 关联映射文件
DOCTYPE configuration
PUBLIC "-//mybatis.org//DTD Config 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-config.dtd">
<configuration>
<environments default="development">
<environment id="development">
<transactionManager type="JDBC"/>
<dataSource type="POOLED">
<property name="driver" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/ssmbuild?useSSL=true&useUnicode=true&characterEncoding=utf8"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
dataSource>
environment>
environments>
<mappers>
<mapper resource="com/oxt/dao/BookMapper.xml"/>
mappers>
configuration>
编写dao.BookMapper接口
public interface BookMapper {
public void addBook(Books books);
public void deleteBookById(int id);
public void updateBook(Books books);
public List<Books> getAllBooks();
}
实现接口,编写映射文件BookMapper.xml
DOCTYPE mapper
PUBLIC "-//mybatis.org//DTD Mapper 3.0//EN"
"http://mybatis.org/dtd/mybatis-3-mapper.dtd">
<mapper namespace="com.oxt.dao.BookMapper">
<select id="allBooks" resultType="com.oxt.pojo.Books">
select * from books
select>
<update id="updateBook" parameterType="com.oxt.pojo.Books">
update ssmbuild.books
set bookName=#{bookName},bookCounts=#{bookCounts},detail=#{detail}
where BOOKID=#{bookId}
update>
<delete id="deleteBookById" parameterType="int">
delete from ssmbuild.books
where BoOkID=#{s}
delete>
<insert id="addBook" parameterType="com.oxt.pojo.Books">
insert into ssmbuild.books(bookName,bookCounts,detail)
values(#{bookName},#{bookCounts},#{detail})
insert>
mapper>
工具类
public class MybatisUtils {
private static SqlSessionFactory sqlSessionFactory;
static {
try {
String resource = "mybatis-config.xml";
InputStream inputStream = Resources.getResourceAsStream(resource);
sqlSessionFactory = new SqlSessionFactoryBuilder().build(inputStream);
} catch (IOException e) {
e.printStackTrace();
}
}
//获取SqlSession连接
public static SqlSession getSession(){
return sqlSessionFactory.openSession();
}
}
编写测试类
public class MyTest {
@Test
public void selectUser() {
SqlSession session = MybatisUtils.getSession();
//方法一:
// List books = session.selectList("com.oxt.dao.BookMapper.allBooks");
//方法二:
BookMapper mapper = session.getMapper(BookMapper.class);
List<Books> books = mapper.getAllBooks();
for (Books book: books){
System.out.println(book);
}
// mapper.addBook(new Books(5,"老人与海",5,"good"));
mapper.deleteBookById(13);
// mapper.updateBook(new Books(13,"老人与海",2222,"better"));
session.commit();
session.close();
}
}
- 创建sqlsessionfactory
- 打开session会话,获取sqlSession连接
- session获取mapper
小结：
- 所有的增删改操作都需要提交事务！
- 接口所有的普通参数，尽量都写上@Param参数，尤其是多个参数时，必须写上！
- 有时候根据业务的需求，可以考虑使用map传递参数！
- 为了规范操作，在SQL的配置文件中，我们尽量将Parameter参数和resultType都写上！
spring-mybatis 整合
导入依赖
- spring
- spring-jdbc操作数据库
- aop植入器
- mybatis-spring整合包
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-webmvcartifactId>
<version>5.1.10.RELEASEversion>
dependency>
<dependency>
<groupId>org.springframeworkgroupId>
<artifactId>spring-jdbcartifactId>
<version>5.1.10.RELEASEversion>
dependency>
<dependency>
<groupId>org.aspectjgroupId>
<artifactId>aspectjweaverartifactId>
<version>1.9.4version>
dependency>
<dependency>
<groupId>org.mybatisgroupId>
<artifactId>mybatis-springartifactId>
<version>2.0.2version>
dependency>
beans.xml
- 数据源,可以是spring自带,c3p0等
- 注入SQLsessionfactory,无需new;并关联mybatis(SQLsessionfactory需要数据源作为参数)
- 注入SQLSessionTemplate,即sqlSession
- 注入bookMapper的实现,该实现类中直接使用sqlSession
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xmlns:aop="http://www.springframework.org/schema/aop"
xsi:schemaLocation="http://www.springframework.org/schema/beans
https://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/aop
https://www.springframework.org/schema/aop/spring-aop.xsd">
<bean id="dataSource" class="org.springframework.jdbc.datasource.DriverManagerDataSource">
<property name="driverClassName" value="com.mysql.jdbc.Driver"/>
<property name="url" value="jdbc:mysql://localhost:3306/ssmbuild?useSSL=true&useUnicode=true&characterEncoding=utf8"/>
<property name="username" value="root"/>
<property name="password" value="root"/>
bean>
<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
<property name="dataSource" ref="dataSource"/>
<property name="configLocation" value="classpath:mybatis-config.xml"/>
bean>
<bean id="sqlSession" class="org.mybatis.spring.SqlSessionTemplate">
<constructor-arg index="0" ref="sqlSessionFactory"/>
bean>
<bean id="bookMapper" class="com.oxt.dao.BookDaoImp">
<property name="sqlSession" ref="sqlSession"/>
bean>
beans>
mybatis-config.xml
<typeAliases>
<package name="com.oxt.pojo"/>
typeAliases>
<mappers>
<package name="com.oxt.dao"/>
mappers>
BookDaoImp
package com.oxt.dao;
import com.oxt.pojo.Books;
import org.mybatis.spring.SqlSessionTemplate;
import java.util.List;
public class BookDaoImp implements BookMapper {
//sqlSession不用我们自己创建了，Spring来管理
private SqlSessionTemplate sqlSession;
public void setSqlSession(SqlSessionTemplate sqlSession) {
this.sqlSession = sqlSession;
}
@Override
public void addBook(Books books) {
BookMapper mapper=sqlSession.getMapper(BookMapper.class);
mapper.addBook(books);
sqlSession.commit();
}
@Override
public void deleteBookById(int id) {
BookMapper mapper=sqlSession.getMapper(BookMapper.class);
mapper.deleteBookById(id);
sqlSession.commit();
}
@Override
public void updateBook(Books books) {
BookMapper mapper=sqlSession.getMapper(BookMapper.class);
mapper.updateBook(books);
sqlSession.commit();
}
@Override
public List<Books> getAllBooks() {
BookMapper mapper = sqlSession.getMapper(BookMapper.class);
return mapper.getAllBooks();
}
}
测试
@Test
public void test(){
ApplicationContext context = new ClassPathXmlApplicationContext("beans.xml");
BookMapper mapper = (BookMapper) context.getBean("bookMapper");
List<Books> book = mapper.getAllBooks();
System.out.println(book);
}
SpringMVC
网页请求与处理过程:
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-
http请求—>Tomcat从磁盘加载servlet
-
Tomcat将http请求转化为request请求对象
-
相应的servlet处理该request请求:转发,重定向,转发即反馈数据,重定向即切换页面
-
tomcat将response转化为http相应
MVC
- Model模型:dao,service 数据模型.
- view 视图jsp
- controller 控制器Servlet,负责接收用户请求和返回响应
典型mvc:javaBean+jsp+servlet
MVC框架要做哪些事情
- 将url映射到java类或 java类的方法.
- 封装用户提交的数据.
- 处理请求–调用相关的业务处理–封装响应数据.
- 将响应的数据进行渲染. jsp/html等表示层数据
Servlet
准备依赖
- servlet
- jsp
<dependency>
<groupId>javax.servletgroupId>
<artifactId>servlet-apiartifactId>
<version>2.5version>
dependency>
<dependency>
<groupId>javax.servlet.jspgroupId>
<artifactId>jsp-apiartifactId>
<version>2.2version>
dependency>
配置web.xml,处理http请求
- 配置处理请求的servlet
- 配置路径处理的mapping
<servlet>
<servlet-name>com.oxt.servlet.HelloServletservlet-name>
<servlet-class>com.oxt.servlet.HelloServletservlet-class>
servlet>
<servlet-mapping>
<servlet-name>com.oxt.servlet.HelloServletservlet-name>
<url-pattern>/userurl-pattern>
servlet-mapping>
编写servlet,处理request请求
@Override
protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
String method = req.getParameter("method");//获取参数
if(method.equals("add")){
req.getSession().setAttribute("msg","执行了add方法");
}else{
req.getSession().setAttribute("msg","没执行add");
}
req.getRequestDispatcher("/WEB-INF/jsp/hello.jsp").forward(req,resp);//视图跳转
}
@Override
protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException {
doGet(req, resp);
}
第一个SpringMVC
配置开发
web.xml
- 同上web.xml,但是servlet变成了DispatcherServlet
<web-app xmlns="https://jakarta.ee/xml/ns/jakartaee"
xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
xsi:schemaLocation="https://jakarta.ee/xml/ns/jakartaee https://jakarta.ee/xml/ns/jakartaee/web-app_5_0.xsd"
version="5.0">
<servlet>
<servlet-name>springmvcservlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServletservlet-class>
<init-param>
<param-name>contextConfigLocationparam-name>
<param-value>classpath:springmvc-servlet.xmlparam-value>
init-param>
<load-on-startup>1load-on-startup>
servlet>
<servlet-mapping>
<servlet-name>springmvcservlet-name>
<url-pattern>/url-pattern>
servlet-mapping>
web-app>
关联的springmvc-servlet.xml
- 处理器
- 处理器适配器
- 视图解析器
- 请求处理类映射
<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">
<bean class="org.springframework.web.servlet.handler.BeanNameUrlHandlerMapping"/>
<bean class="org.springframework.web.servlet.mvc.SimpleControllerHandlerAdapter"/>
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver" id="InternalResourceViewResolver">
<property name="prefix" value="/WEB-INF/jsp/"/>
<property name="suffix" value=".jsp"/>
bean>
<bean id="/hello" class="com.oxt.controller.HelloController"/>
beans>
- hello请求从xx-servlet.xml转到相应的处理器
public class HelloController implements Controller {
public ModelAndView handleRequest(HttpServletRequest request, HttpServletResponse response) throws Exception {
//ModelAndView 模型和视图
ModelAndView mv = new ModelAndView();
//封装对象，放在ModelAndView中。Model
mv.addObject("msg","HelloSpringMVC!");
//封装要跳转的视图，放在ModelAndView中
mv.setViewName("hello"); //: /WEB-INF/jsp/hello.jsp
return mv;
}
}
- 实现接口,导入接口的包org.springframework.web.servlet.mvc.Controller;
注解开发
web.xml
- 注册DispatcherServlet
<servlet>
<servlet-name>SpringMVChereservlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServletservlet-class>
<init-param>
<param-name>contextConfigLocationparam-name>
<param-value>classpath:springmvc-servlet.xmlparam-value>
init-param>
<load-on-startup>1load-on-startup>
servlet>
- 设置springmvc拦截请求
<servlet-mapping>
<servlet-name>SpringMVChereservlet-name>
<url-pattern>/url-pattern>
servlet-mapping>
12成双
resources下建立springmvc-servlet.xml
<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/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
http://www.springframework.org/schema/mvc
https://www.springframework.org/schema/mvc/spring-mvc.xsd">
- 自动扫描包:该包下的
注解生效,由IOC容器管理
<context:component-scan base-package="com.oxt.controller"/>
- 不让SpringMVC处理静态资源
在 WEB 容器启动的时候会在上下文中定义一个 DefaultServletHttpRequestHandler，它会对DispatcherServlet的请求进行处理，如果该请求已经作了映射，那么会接着交给后台对应的处理程序，如果没有作映射，就交给 WEB 应用服务器默认的 Servlet 处理，从而找到对应的静态资源，只有再找不到资源时才会报错。点击查看原文
如果想要解决访问静态资源问题，通常会使用默认handler：
<mvc:default-servlet-handler />
3.处理器和适配器
<mvc:annotation-driven />
- 视图解析器
<bean class="org.springframework.web.servlet.view.InternalResourceViewResolver">
<property name="viewClass" value="org.springframework.web.servlet.view.JstlView" />
<property name="prefix" value="/WEB-INF/jsp/" />
<property name="suffix" value=".jsp" />
bean>
com.oxt.controller.HelloController
@Controller
@RequestMapping("/helloController")//类请求
public class HelloController{
@RequestMapping("hello")
pubulic String helloC(Model model){
model.addAttribute("msg","hello,you,how");
return "hello";//返回页面 视图解析加上前后缀:/WEB-INF/jsp/hello.jsp
}
}
hello.jsp
<%@ page contentType="text/html;charset=UTF-8" language="java" %>
SpringMVC
${msg}
小结
实现步骤其实非常的简单：
- 新建一个web项目
- 导入相关jar包
- 编写web.xml , 注册DispatcherServlet
- 编写springmvc配置文件
- 接下来就是去创建对应的控制类 , controller
- 最后完善前端视图和controller之间的对应
- 测试运行调试.
使用springMVC必须配置的三大件：
处理器映射器、处理器适配器、视图解析器
通常，我们只需要手动配置视图解析器，而处理器映射器和处理器适配器只需要开启注解驱动即可，而省去了大段的xml配置
web.xml中的dispatchcer servlet用的spring总文件
spring总文件中import三层文件:springmvc,dao,service
springdao.xml中:数据源,sqlSessionFactory,
SSM整合
导入依赖
sprig+mybatis
1.编写pojo
2.编写mapper类和映射文件
3.编写service层
编写配置文件
1.spring总文件applicationContext.xml:import三层的xml文件,实际上就是一个spring文件
2.spring-dao.xml
在spring-mybatis中,用factory获取sqlsession,factory需要映射文件作为参数,sqlsession获取相应的mapper类 然后增删改查操作
- 引入database.properties
标签为
ssm加上classpath:才正常运行,仅用于spring-mybatis可以不加 - bean:dataSource
- bean:SQLSessionFactory ,需要注入映射文件mybatis
(mybatis文件中设置别名typeAliases 以及mappers标签中设置映射文件位置) - bean:配置class MapperScannerConfigurer 需要注入sqlsessionfactory
扫描dao层的类,自动注册各个mapper类的bean
3.spring-service.xml
- import spring-dao
- 扫描service层
- bean:serviceImp
- bean:事务管理器
spring+springmvc
idea中要注意在web文件夹中添加lib依赖
web.xml
1.servlet 指定总spring配置文件
2.servlet-mapping 指定/请求处理的servlet↑
3.filter拦截请求
4.session过期时间
conroller层类编写
1.@Controller标记
2.RequestMapping,类中和方法上
3.bean:bookService 使用@AutoWired和@Qualifier指定
3.编写各个请求的处理方法 String name(Model model){return jsp页面}
4.编写相应的jsp
spring-mvc.xml
1.注解驱动
2.静态视图资源 使用默认servlet
3.视图解析 前后缀
4.扫描controller包