Spring4 + Spring MVC + MyBatis 整

1、Spring框架的搭建

这个很简单，只需要web容器中注册org.springframework.web.context.ContextLoaderListener，并指定spring加载配置文件，那么spring容器搭建完成。（当然org.springframework的核心jar包需要引入）

当然为了更加易用支持J2EE应用，一般我们还会加上如下：

Spring监听HTTP请求事件：org.springframework.web.context.request.RequestContextListener

<!-- spring配置文件开始 -->

    <context-param>

        <param-name>contextConfigLocation</param-name><!-- spring配置文件，请根据需要选取 -->

        <param-value>classpath*:webconfig/service-all.xml</param-value>

    </context-param>

    <listener><!-- Spring负责监听web容器启动和关闭的事件 --><!-- Spring ApplicationContext载入 -->

        <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class>

    </listener>

    <listener><!-- Spring监听HTTP请求事件 -->

        <!-- 使spring支持request与session的scope,如: -->

        <!-- <bean id="loginAction"class="com.foo.LoginAction"scope="request"/> -->

        <!-- 使用： -->

        <!-- 1、注解获取：@AutowiredHttpServletRequest request; -->

        <!-- 2、java代码：HttpServletRequest request =

        ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest(); -->

        <!-- 3、直接在参数中传递：publicString sayHi(HttpServletRequest request) -->

        <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class>

    </listener>

    <listener><!-- Spring 刷新Introspector防止内存泄露 -->

        <listener-class>org.springframework.web.util.IntrospectorCleanupListener</listener-class>

    </listener>

    <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>

        <init-param>

            <param-name>forceEncoding</param-name>

            <param-value>false</param-value>

        </init-param>

    </filter>

    <filter-mapping>

        <filter-name>encodingFilter</filter-name>

        <url-pattern>/*</url-pattern>

    </filter-mapping>

    <!-- spring配置文件结束 -->

2、Spring MVC的搭建

首先我们知道Spring MVC的核心是org.springframework.web.servlet.DispatcherServlet，所以web容器中少不了它的注册。（当然org.springframework的web、mvc包及其依赖jar包需要引入）

<!-- spring mvc配置开始 -->

    <servlet>

        <servlet-name>Spring-MVC</servlet-name>

        <servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>

        <init-param>

            <param-name>contextConfigLocation</param-name>

            <param-value>classpath*:spring/spring-mvc.xml</param-value><!-- spring mvc配置文件 -->

        </init-param>

        <load-on-startup>1</load-on-startup>

    </servlet>

    <servlet-mapping>

        <servlet-name>Spring-MVC</servlet-name>

        <url-pattern>*.do</url-pattern>

    </servlet-mapping>

    <!-- spring mvc配置结束 -->

同时为了更好使用MVC，spring-mvc.xml需要配置以下：

1）（可选）多部分请求解析器（MultipartResolver）配置，与上传文件有关 需要类库commons-io、commons-fileupload

<bean id="multipartResolver"class="org.springframework.web.multipart.commons.CommonsMultipartResolver">

        <property name="defaultEncoding"value="utf-8"></property><!-- 默认编码-->

        <property name="maxUploadSize"value="104857600"></property><!-- 文件大小最大值-->

        <property name="maxInMemorySize"value="40960"></property><!-- 内存中的最大值-->

    </bean>

2）（可选）本地化（LocaleResolver）配置

3）（可选）主题解析器（ThemeResolver）配置

4）（必选）处理器映射器（HandlerMapping）配置，可以配置多个，一般采用RequestMappingHandlerMapping或者自定义

这里我们自定义了一个处理器映射器，继承重写RequestMappingHandlerMapping，支持@RequestMapping无需任何path参数自动装载类名或方法作为url路径匹配。

<bean id="handlerMapping"

        class="io.flysium.framework.web.servlet.mvc.method.annotation.CustomHandlerMapping">

        <property name="order"value="-1"/>

    </bean>

CustomHandlerMapping实现：

@Override

    protectedRequestMappingInfo getMappingForMethod(Method method, Class handlerType) {

        RequestMappingInfo info = createRequestMappingInfoDefault(method);

        if(info != null) {

            RequestMappingInfo typeInfo = createRequestMappingInfoDefault(handlerType);

            if(typeInfo != null)

                info = typeInfo.combine(info);

        }

        returninfo;

    }

    privateRequestMappingInfo createRequestMappingInfoDefault(AnnotatedElement element) {

        RequestMapping requestMapping = AnnotatedElementUtils.findMergedAnnotation(element,

                RequestMapping.class);

        RequestCondition condition = (element instanceofClass)

                ? getCustomTypeCondition((Class) element)

                : getCustomMethodCondition((Method) element);

        /**

        * 以类名和方法名映射请求，参照@RequestMapping

        * 默认不需要添加任何参数(如：/className/methodName.do)

        */

        String defaultName = (element instanceofClass)

                ? ((Class) element).getSimpleName()

                : ((Method) element).getName();

        returnrequestMapping == null

                ? null

                : createRequestMappingInfo(requestMapping, condition, defaultName);

    }

    protectedRequestMappingInfo createRequestMappingInfo(RequestMapping annotation,

            RequestCondition<?> customCondition, String defaultName) {

        String[] patterns = resolveEmbeddedValuesInPatterns(annotation.value());

        if(patterns != null&& (patterns.length == 0)) {

            patterns = newString[]{defaultName};

        }

        returnnewRequestMappingInfo(

                newPatternsRequestCondition(patterns, getUrlPathHelper(), getPathMatcher(),

                        this.useSuffixPatternMatch, this.useTrailingSlashMatch,

                        this.fileExtensions),

                newRequestMethodsRequestCondition(annotation.method()),

                newParamsRequestCondition(annotation.params()),

                newHeadersRequestCondition(annotation.headers()),

                newConsumesRequestCondition(annotation.consumes(), annotation.headers()),

                newProducesRequestCondition(annotation.produces(), annotation.headers(),

                        this.contentNegotiationManager),

                customCondition);

    }

5）（必选）处理器适配器（HandlerAdapter）配置，可以配置多个，主要是配置messageConverters，其主要作用是映射前台传参与handler处理方法参数。一般扩展RequestMappingHandlerAdapter，或者自定义。如果我们需要json请求的处理，这里必须扩展。同时我们需要注意的是日期格式的转换。

另外Spring 4.2新特性，加之注解会自动注入@ControllerAdvice，可以定义RequestBodyAdvice、ResponseBodyAdvice，可以更方便地在参数处理方面着手自定义。

<bean id="handlerAdapter"

    class="org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter">

    <property name="order"value="-1"/>

    <property name="messageConverters">

        <list>

        <!-- <bean class="org.springframework.http.converter.json.MappingJackson2HttpMessageConverter"

            /> -->

            <ref bean="mappingJacksonHttpMessageConverter"/>

        </list>

    </property>

    <property name="webBindingInitializer">

        <bean

            class="org.springframework.web.bind.support.ConfigurableWebBindingInitializer">

            <property name="conversionService">

                <!-- 针对普通请求(非application/json) 前台的日期字符串与后台的Java Date对象转化,

                此情况,应使用spring

                    mvc本身的内置日期处理 -->

                <!-- 可以在VO属性上加注解：@DateTimeFormat需要类库joda-time -->

        <bean

        class="org.springframework.format.support.FormattingConversionServiceFactoryBean">

        </bean>

            </property>

        </bean>

    </property>

</bean>

<!-- json请求(application/json)返回值Date转String，全局配置 -->

<bean name="jacksonObjectMapper"

    class="org.springframework.http.converter.json.Jackson2ObjectMapperFactoryBean">

    <property name="featuresToDisable">

        <array>

        <util:constant

static-field="com.fasterxml.jackson.databind.SerializationFeature.WRITE_DATES_AS_TIMESTAMPS"/>

        </array>

    </property>

    <!-- 如果想自定义，可以在VO属性上加注解：@JsonFormat(shape = JsonFormat.Shape.STRING, pattern

        = Consts.DATE_PATTERN.DATE_PATTERN_OBLIQUE,timezone = "GMT+8") -->

    <property name="simpleDateFormat">

        <value>yyyy-MM-dd HH:mm:ss</value>

    </property>

</bean>

<!--避免IE执行Ajax时，返回JSON出现下载文件 -->

<!-- 自定义 -->

<bean id="mappingJacksonHttpMessageConverter"

    class="io.flysium.framework.http.converter.json.CustomJackson2HttpMessageConverter">

    <property name="objectMapper"ref="jacksonObjectMapper"/>

    <property name="supportedMediaTypes">

        <list>

            <value>text/html;charset=UTF-8</value>

            <value>application/json;charset=UTF-8</value>

        </list>

    </property>

</bean>

6）（可选）处理器异常解析器（HandlerExceptionResolver）配置，可以配置多个，配置Controller异常抛出后，我们是怎么样处理的，一般需要日志或做反馈的可以自定义。

7）（可选）请求到视图名翻译器（RequestToViewNameTranslator）配置，RequestToViewNameTranslator可以在处理器返回的View为空时使用它根据Request获得viewName。

8）（可选）视图解析器（ViewResolver）配置，可以配置多个，定义跳转的文件的前后缀 ，视图模式配置，主要针对@Controller返回ModelAndView的视图路径解析，动给后面控制器的方法return的字符串 加上前缀和后缀，变成一个 可用的url地址 。

<bean id="viewResolver"

        class="org.springframework.web.servlet.view.InternalResourceViewResolver">

        <property name="prefix"value="/"/>

        <property name="suffix"value=".jsp"/>

        <property name="viewClass"

            value="org.springframework.web.servlet.view.JstlView"/>

    </bean>

最后给Controller加入组件扫描吧，这样减少xml配置，直接在Java代码中加入注解即可。

<!-- 自动扫描类包，将标志Spring注解的类自动转化为Bean，同时完成Bean的注入 -->

<!-- 扫描控制器 -->

<context:component-scan base-package="io.flysium"use-default-filters="false">

    <context:include-filter type="annotation"

        expression="org.springframework.stereotype.Controller"/>

    <context:include-filter type="annotation"

        expression="org.springframework.web.bind.annotation.RestController"/>

    <context:include-filter type="annotation"

        expression="org.springframework.web.bind.annotation.ControllerAdvice"/>

</context:component-scan>

3、Mybatis整合

整合mybatis到Spring框架，我们需要mybatis的jar包，及mybatis-spring整合jar包。然后在Spring容器中注册配置org.mybatis.spring.SqlSessionFactoryBean（需要数据源，及指定Mybatis配置文件）及org.mybatis.spring.SqlSessionTemplate即可。