Spring MVC

Spring MVC 环境搭建

引入 spring-mvc 相关依赖

<dependencies>
  <dependency>
    <groupId>javax.servlet</groupId>
    <artifactId>servlet-api</artifactId>
    <version>2.5</version>
    <scope>provided</scope>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
  </dependency>
</dependencies>

在web.xml中配置DispatcherServlet

<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>0</load-on-startup>
</servlet>
<servlet-mapping>
  <servlet-name>springmvc</servlet-name>
  <url-pattern>/</url-pattern>
</servlet-mapping>

创建并配置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"
       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 
       https://www.springframework.org/schema/context/spring-context.xsd 
       http://www.springframework.org/schema/mvc 
       https://www.springframework.org/schema/mvc/spring-mvc.xsd">

    <context:component-scan base-package="person.xianglin.springmvc"/>
    <mvc:annotation-driven/>
    <mvc:default-servlet-handler/>
</beans>

开发业务代码

SpringMVC 基础及数据绑定

URL 绑定

@RequestMapping

接收请求参数

方法参数接收请求数据
@RequestParam
JavaBean 接收请求参数

日期类型转换

@DateTimeFormat

实现org.springframework.core.convert.converter.Converter自定义转换

public class DateConverter implements Converter<String, Date> {
    @Override
    public Date convert(String s) {
        DateFormat dateFormat = new SimpleDateFormat("yyyy-MM-dd");
        Date parse = null;
        try {
            parse = dateFormat.parse(s);
            return parse;
        } catch (ParseException e) {
            return null;
        }
    }
}

<context:component-scan base-package="person.xianglin.springmvc"/>
<mvc:default-servlet-handler/>
<mvc:annotation-driven conversion-service="conversionService"/>

<bean id="conversionService" class="org.springframework.format.support.FormattingConversionServiceFactoryBean">
  <property name="converters">
    <set>
      <bean class="person.xianglin.springmvc.convert.DateConverter"/>
    </set>
  </property>
</bean>

Spring MVC 中文乱码

Get 请求：server.xml中增加URIEncoding属性（Tomcat8.0 之前）

<Connector port="8080" protocol="HTTP/1.1"
               connectionTimeout="20000"
               redirectPort="8443" URIEncoding="UTF-8"/>

Post 请求：web.xml中配置CharacterEncodingFilter

<filter>
  <filter-name>characterFilter</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>characterFilter</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>

Response 响应：Spring 配置StringHttpMessageConverter

<mvc:annotation-driven>
  <mvc:message-converters>
    <bean class="org.springframework.http.converter.StringHttpMessageConverter">
      <property name="supportedMediaTypes">
        <list>
          <value>application/json;charset=utf-8</value>
          <value>text/html;charset=utf-8</value>
        </list>
      </property>
    </bean>
  </mvc:message-converters>
</mvc:annotation-driven>

响应输出结果

@ResponseBody
ModelAndView
属性保存在当前请求 request 对象中
modelAndView 使用请求转发完成页面跳转
使用redirect:index.html完成重定向

Spring 与模板引擎整合

引入 freemaker 依赖

<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-context-support</artifactId>
</dependency>
<dependency>
  <groupId>org.freemarker</groupId>
  <artifactId>freemarker</artifactId>
  <version>2.3.30</version>
</dependency>

配置FreeMarkerViewResolver

<bean id="viewResolver" class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">
  <property name="contentType" value="text/html;charset=UTF-8"/>
  <property name="suffix" value=".ftl"/>
</bean>

配置FreeMarkerConfig

<!-- NoSuchBeanDefinitionException: No qualifying bean of type 'org.springframework.web.servlet.view.freemarker.FreeMarkerConfig' available -->
<bean id="freeMarkerConfig" class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">
  <property name="templateLoaderPath" value="/WEB-INF/ftl/"/>
  <property name="freemarkerSettings">
    <props>
      <prop key="defaultEncoding">UTF-8</prop>
    </props>
  </property>
</bean>

Restful风格的应用

REST：表现层状态转换，资源在网络中以某种形式进行状态转换
RESTFul 开发规范：
1. 使用 URL 作为用户交互入口
2. 明确的语义规范，使用不同的 HTTP 方法完成对应的操作
3. 只返回数据，不包含展示

SpringMVC RESTFul 使用

@RestController 创建 RestFul 风格控制器对象
@PathVariable 路径变量注解

非简单请求JavaBean无法获取参数问题

在web.xml中配置FormContentFilter过滤器

<filter>
  <filter-name>formContextFilter</filter-name>
  <filter-class>org.springframework.web.filter.FormContentFilter</filter-class>
</filter>
<filter-mapping>
  <filter-name>formContextFilter</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>

jackson 中对日期格式的注解@JsonFormat

@JsonFormat(pattern = "yyyy-MM-dd HH:mm:ss SSS",timezone = "Asia/Shanghai")
private Date date;

跨域问题

同源策略阻止从一个域加载脚本去获取另一个域上的资源
只要协议、域名、端口有一个不同，都视为不同的域
Access-Control-Allow-Origin

HTML 中允许跨域的标签

<img> 图片
<srcipt> JS 脚本
link CSS 样式

SpringMVC 解决跨域访问问题

@CrosOrigin Controller 跨域注解

字段	描述	值
origins	被允许跨区请求的源列表
allowedHeaders	被允许在实际请求中的请求头	`Access-Control-Allow-Headers`
exposedHeaders		`Access-Control-Expose-Headers`
methods	支持的HTTP请求方法的列表
allowCredentials		`Access-Control-Allow-Credentials`
maxAge	预检响应缓存持续时间	`Access-Control-Max-Age`

<mvc:cros> 全局跨域设置

<mvc:cors>
    <mvc:mapping path="/restful/**" allowed-origins="http://127.0.0.1,http://example.com" max-age="3600"/>
</mvc:cors>

Spring 拦截器

拦截器（Interceptor）用于对请求进行前置、后置过滤
拦截器基于 Spring AOP 实现

Spring 拦截器开发流程

引入servlet-api

<dependency>
  <groupId>javax.servlet</groupId>
  <artifactId>javax.servlet-api</artifactId>
  <version>3.1.0</version>
  <scope>provided</scope>
</dependency>

继承org.springframework.web.servlet.HandlerInterceptor实现拦截器逻辑

配置拦截器

<mvc:interceptors>
  <mvc:interceptor>
    <mvc:mapping path="/**"/>
    <bean class="person.xianglin.springrestful.interceptor.MyInterceptor"/>
  </mvc:interceptor>
</mvc:interceptors>

HandlerInterceptor 接口

方法	描述
preHandle	前置执行处理：返回 true 允许执行后续操作，返回 false 则立即返回
postHandle	目标资源已被 SpringMVC框架处理
afterCompletion	响应文本已经产生

拦截器处理 URL

资源过滤

<mvc:exclude-mapping path="/**.ico"/>
<mvc:exclude-mapping path="/resources/**"/>

多个拦截器执行顺序

Spring MVC 处理流程

SSM 整合过程

Spring与 SpringMVC环境配置

在pom.xml中引入相应依赖

<dependencies>
  <!-- SpringMVC 依赖 -->
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-webmvc</artifactId>
  </dependency>
  <!-- Freemarker 依赖 -->
  <dependency>
    <groupId>org.freemarker</groupId>
    <artifactId>freemarker</artifactId>
    <version>2.3.30</version>
  </dependency>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-context-support</artifactId>
  </dependency>
  <!-- Jackson 依赖 -->
  <dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-core</artifactId>
    <version>2.11.1</version>
  </dependency>
  <dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-annotations</artifactId>
    <version>2.11.1</version>
  </dependency>
  <dependency>
    <groupId>com.fasterxml.jackson.core</groupId>
    <artifactId>jackson-databind</artifactId>
    <version>2.11.1</version>
  </dependency>
</dependencies>

在web.xml中声明ContextLoaderListener和DispatcherServlet

ContextLoaderListener用于初始化 IOC 容器，DispatcherServlet用于初始化 SpringMVC 相关内容

<!-- 将 Spring 的配置信息以 context-param 的方式注册，并让ContextLoaderListener 进行读取-->
<context-param>
  <param-name>contextConfigLocation</param-name>
  <param-value>classpath:applicationContext.xml</param-value>
</context-param>
<listener>
  <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>
</listener>

<servlet>
  <servlet-name>springmvc</servlet-name>
  <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
  <!-- 指定 spring-mvc 配置文件路径 -->
  <init-param>
    <param-name>contextConfigLocation</param-name>
    <param-value>classpath:spring-mvc.xml</param-value>
  </init-param>
  <!-- 让DispatcherServlet在应用启动时初始化 -->
  <load-on-startup>1</load-on-startup>
</servlet>
<servlet-mapping>
  <servlet-name>springmvc</servlet-name>
  <url-pattern>/</url-pattern>
</servlet-mapping>

处理请求响应中的中文乱码问题

在web.xml中声明CharacterEncodingFilter用于处理请求中的乱码问题

<filter>
  <filter-name>characterFilter</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>characterFilter</filter-name>
  <url-pattern>/*</url-pattern>
</filter-mapping>

在spring-mvc.xml中使用<mvc:message-converters>标签处理响应中的乱码问题

<mvc:message-converters>
  <bean class="org.springframework.http.converter.StringHttpMessageConverter">
    <property name="supportedMediaTypes">
      <list>
        <value>text/html;charset=utf-8</value>
        <value>application/json;charset=utf-8</value>
      </list>
    </property>
  </bean>
</mvc:message-converters>

创建spring-mvc.xml配置 spring mvc相关配置

<!-- 指定扫描 controller 包 -->
<context:component-scan base-package="person.xianglin.reader.controller"/>
<!-- 启用 mvc 注解开发 -->
<mvc:annotation-driven>
  <mvc:message-converters>
    <bean class="org.springframework.http.converter.StringHttpMessageConverter">
      <property name="supportedMediaTypes">
        <list>
          <value>text/html;charset=utf-8</value>
          <value>application/json;charset=utf-8</value>
        </list>
      </property>
    </bean>
  </mvc:message-converters>
</mvc:annotation-driven>
<!-- 处理静态资源：将静态资源转发至 Tomcat 的默认Servlet 中 -->
<mvc:default-servlet-handler/>

在spring-mvc.xml中整合模板引擎（Freemarker），同时在创建指定目录WEB-INF/ftl

<bean id="freeMarkerConfig" class="org.springframework.web.servlet.view.freemarker.FreeMarkerConfigurer">
  <property name="templateLoaderPath" value="/WEB-INF/ftl/"/>
  <property name="freemarkerSettings">
    <props>
      <prop key="defaultEncoding">UTF-8</prop>
    </props>
  </property>
</bean>
<bean id="viewResolver" class="org.springframework.web.servlet.view.freemarker.FreeMarkerViewResolver">
  <property name="contentType" value="text/html;charset=utf-8"/>
  <property name="suffix" value=".ftl"/>
</bean>

如果使用 JSP ，可配置InternalResourceViewResolver

<bean id="internalResourceViewResolver" class="org.springframework.web.servlet.view.InternalResourceViewResolver">
  <property name="prefix" value="/WEB-INF/jsp/"/>
  <property name="suffix" value=".jsp"/>
</bean>

编写测试用的TestController

@Controller
@RequestMapping(value = "/test")
public class TestController {
    @GetMapping(value = "/t1")
    public ModelAndView test1() {
        ModelAndView modelAndView = new ModelAndView("test");
        modelAndView.addObject("test", "/test/t1");
        return modelAndView;
    }

    @GetMapping(value = "/t2")
    @ResponseBody
    public Map<String, Object> test2() {
        Map<String, Object> map = new HashMap<>(3);
        map.put("success", true);
        return map;
    }
}

Spring 与 MyBatis 整合

在pom.xml中引入依赖

<dependencies>
  <dependency>
    <groupId>org.springframework</groupId>
    <artifactId>spring-jdbc</artifactId>
  </dependency>
  <dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis</artifactId>
    <version>3.5.5</version>
  </dependency>
  <dependency>
    <groupId>org.mybatis</groupId>
    <artifactId>mybatis-spring</artifactId>
    <version>2.0.5</version>
  </dependency>
  <dependency>
    <groupId>mysql</groupId>
    <artifactId>mysql-connector-java</artifactId>
    <version>8.0.20</version>
  </dependency>
  <dependency>
    <groupId>com.alibaba</groupId>
    <artifactId>druid</artifactId>
    <version>1.1.23</version>
  </dependency>
</dependencies>

在applicationContext.xml中配置数据源与连接池

<bean id="dataSource" class="com.alibaba.druid.pool.DruidDataSource">
  <property name="driverClassName" value="com.mysql.cj.jdbc.Driver"/>
  <property name="url" value="jdbc:mysql://122.51.48.52:3306/imooc_reader?useSSL=false&amp;useUnicode=true"/>
  <property name="username" value=""/>
  <property name="password" value=""/>
  <property name="initialSize" value="5"/>
  <property name="maxActive" value="20"/>
</bean>

在applicationContext.xml中配置SqlSessionFactoryBean和MapperScannerConfigurer，用于将 MyBatis 的 SQLSession 和 Mapper 交于 Spring 管理

<bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">
  <property name="dataSource" ref="dataSource"/>
  <property name="mapperLocations" value="classpath:mappers/*.xml"/>
  <property name="configLocation" value="classpath:mybatis-config.xml"/>
</bean>

<bean class="org.mybatis.spring.mapper.MapperScannerConfigurer">
  <property name="basePackage" value="person.xianglin.reader.mapper"/>
</bean>

配置其他组件

配置logback日志输出

引入logback依赖

<dependency>
  <groupId>ch.qos.logback</groupId>
  <artifactId>logback-classic</artifactId>
  <version>1.2.3</version>
</dependency>

创建logback.xml配置文件

<?xml version="1.0" encoding="UTF-8" ?>
<configuration>
    <appender name="console" class="ch.qos.logback.core.ConsoleAppender">
        <encoder class="ch.qos.logback.classic.encoder.PatternLayoutEncoder">
            <pattern>%d{HH:mm:ss} %-5level [%thread] %logger{30} -%msg%n</pattern>
            <charset>UTF-8</charset>
        </encoder>
    </appender>
    <root level="debug">
        <appender-ref ref="console"/>
    </root>
</configuration>

声明式事务配置

在applicationContext.xml配置

<bean id="transactionManager" class="org.springframework.jdbc.datasource.DataSourceTransactionManager">
  <property name="dataSource" ref="dataSource"/>
</bean>
<tx:annotation-driven/>

整合 JUnit 单元测试

引入依赖

<dependency>
  <groupId>org.springframework</groupId>
  <artifactId>spring-test</artifactId>
</dependency>
<dependency>
  <groupId>junit</groupId>
  <artifactId>junit</artifactId>
  <version>4.13</version>
  <scope>test</scope>
</dependency>

编写测试类

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath:applicationContext.xml"})
public class TestServiceTest {

    @Resource
    private TestService testService;

    @Test
    public void insert() {
        testService.insert();
    }
}

配置 MyBatis-Plus

在pom.xml中引入依赖

<dependency>
  <groupId>com.baomidou</groupId>
  <artifactId>mybatis-plus</artifactId>
  <version>3.4.0</version>
</dependency>

调整applicationContext.xml中的SqlSessionFactory

<!--    <bean id="sqlSessionFactory" class="org.mybatis.spring.SqlSessionFactoryBean">-->
<bean id="sqlSessionFactory" class="com.baomidou.mybatisplus.extension.spring.MybatisSqlSessionFactoryBean">
  <property name="dataSource" ref="dataSource"/>
  <property name="mapperLocations" value="classpath:mappers/*.xml"/>
  <property name="configLocation" value="classpath:mybatis-config.xml"/>
</bean>

在mybatis-config.xml中增加分页插件

<plugins>
  <plugin interceptor="com.baomidou.mybatisplus.extension.plugins.PaginationInterceptor"/>
</plugins>

MyBatis-Plus 使用步骤

创建实体类

@Data
@TableName("test")
public class Test {
    @TableId(type = IdType.AUTO)
    @TableField("id")
    private Integer id;
    @TableField("context")
    private String context;
}

@TableName
@TableId
@TableField

创建 Mapper 接口和MapperXML

继承自com.baomidou.mybatisplus.core.mapper.BaseMapper

public interface TestMapper extends BaseMapper<Test> {
    void insertSample();
}

注入 Mapper对象，通过内置 API 完成 CURD 操作

@RunWith(SpringJUnit4ClassRunner.class)
@ContextConfiguration(locations = {"classpath:applicationContext.xml"})
public class TestMapperTest {
    @Resource
    private TestMapper testMapper;

    @org.junit.Test
    public void testInsert() {
        Test test = new Test();
        test.setContext("MyBatis-Plus 测试");
        testMapper.insert(test);
    }

    @org.junit.Test
    public void testUpdate() {
        Test test = testMapper.selectById(8);
        test.setContext("测试 1111");
        testMapper.updateById(test);
    }

    @org.junit.Test
    public void testSelectList() {
        QueryWrapper<Test> queryWrapper = new QueryWrapper<>();
        queryWrapper.ge("id", 8);
        List<Test> selectList = testMapper.selectList(queryWrapper);
        Assert.assertEquals(selectList.size(), 1);
    }
}

insert、updateById、deleteById、selectById、selectList、selectPage

Kaptcha 验证码

引入依赖

<dependency>
  <groupId>com.github.penggle</groupId>
  <artifactId>kaptcha</artifactId>
  <version>2.3.2</version>
</dependency>

配置com.google.code.kaptcha.Producer实现类

<bean id="defaultKaptcha" class="com.google.code.kaptcha.impl.DefaultKaptcha">
  <property name="config">
    <bean class="com.google.code.kaptcha.util.Config">
      <constructor-arg name="properties">
        <props>
          <prop key="kaptcha.border">no</prop>
          <prop key="kaptcha.image.width">120</prop>
          <prop key="kaptcha.textproducer.font.color">blue</prop>
          <prop key="kaptcha.textproducer.font.size">40</prop>
          <prop key="kaptcha.textproducer.char.length">4</prop>
        </props>
      </constructor-arg>
    </bean>
  </property>
</bean>

在 controller 中使用

@Controller
public class KaptchaController {
    @Resource
    private Producer defaultKaptcha;

    @GetMapping(value = "/verify_code")
    public void createVerifyCode(HttpServletRequest request, HttpServletResponse response) throws IOException {
        response.setDateHeader("Expires", 0);
        response.setHeader("Cache-Control", "no-store,no-cache,must-revalidate");
        response.setHeader("Cache-Control", "post-check=0;pre-check=0");
        response.setHeader("Pragma", "no-cache");
        response.setContentType("image/png");

        String verifyCode = defaultKaptcha.createText();
        request.getSession().setAttribute("kaptchaVerifyCode", verifyCode);
        BufferedImage kaptchaImage = defaultKaptcha.createImage(verifyCode);
        ServletOutputStream outputStream = response.getOutputStream();
        ImageIO.write(kaptchaImage, "png", outputStream);
        outputStream.flush();
        outputStream.close();
    }
}

Spring MVC#

Spring MVC 环境搭建#

SpringMVC 基础及数据绑定#

URL 绑定#

接收请求参数#

Spring MVC 中文乱码#

响应输出结果#

Restful风格的应用#

SpringMVC RESTFul 使用#

跨域问题#

HTML 中允许跨域的标签#

SpringMVC 解决跨域访问问题#

Spring 拦截器#

Spring 拦截器开发流程#

HandlerInterceptor 接口#

拦截器处理 URL#

Spring MVC 处理流程#

SSM 整合过程#

Spring与 SpringMVC环境配置#

Spring 与 MyBatis 整合#

配置其他组件#

配置 MyBatis-Plus#

MyBatis-Plus 使用步骤#

Kaptcha 验证码#