Spring4+Spring MVC+MyBatis整合思路
1、Spring框架的搭建
這個很簡單,只需要web容器中註冊org.springframework.web.context.ContextLoaderListener,並指定spring載入配置檔案,那麼spring容器搭建完成。(當然org.springframework的核心jar包需要引入)
當然為了更加易用支援J2EE應用,一般我們還會加上如下:
Spring監聽HTTP請求事件:org.springframework.web.context.request.RequestContextListener
<!-- spring配置檔案開始 --> <context-param> <param-name>contextConfigLocation</param-name><!-- spring配置檔案,請根據需要選取 --> <param-value>classpath*:webconfig/service-all.xml</param-value> </context-param> <listener><!-- Spring負責監聽web容器啟動和關閉的事件 --><!-- Spring ApplicationContext載入 --> <listener-class>org.springframework.web.context.ContextLoaderListener</listener-class> </listener> <listener><!-- Spring監聽HTTP請求事件 --> <!-- 使spring支援request與session的scope,如: --> <!-- <bean id="loginAction" class="com.foo.LoginAction" scope="request"/> --> <!-- 使用: --> <!-- 1、註解獲取:@Autowired HttpServletRequest request; --> <!-- 2、java程式碼:HttpServletRequest request = ((ServletRequestAttributes)RequestContextHolder.getRequestAttributes()).getRequest(); --> <!-- 3、直接在引數中傳遞:public String sayHi(HttpServletRequest request) --> <listener-class>org.springframework.web.context.request.RequestContextListener</listener-class> </listener> <listener><!-- Spring 重新整理Introspector防止記憶體洩露 --> <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配置檔案結束 -->
2、Spring MVC的搭建
首先我們知道Spring MVC的核心是org.springframework.web.servlet.DispatcherServlet,所以web容器中少不了它的註冊。(當然org.springframework的web、mvc包及其依賴jar包需要引入)
<!-- spring mvc配置開始 --> <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配置檔案 --> </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配置結束 -->
同時為了更好使用MVC,spring-mvc.xml需要配置以下:
1)(可選)多部分請求解析器(MultipartResolver)配置,與上傳檔案有關 需要類庫commons-io、commons-fileupload
<bean id="multipartResolver" class="org.springframework.web.multipart.commons.CommonsMultipartResolver"> <property name="defaultEncoding" value="utf-8"></property><!-- 預設編碼--> <property name="maxUploadSize" value="104857600"></property><!-- 檔案大小最大值--> <property name="maxInMemorySize" value="40960"></property><!-- 記憶體中的最大值--> </bean>
2)(可選)本地化(LocaleResolver)配置
3)(可選)主題解析器(ThemeResolver)配置
4)(必選)處理器對映器(HandlerMapping)配置,可以配置多個,一般採用RequestMappingHandlerMapping或者自定義
這裡我們自定義了一個處理器對映器,繼承重寫RequestMappingHandlerMapping,支援@RequestMapping無需任何path引數自動裝載類名或方法作為url路徑匹配。
<bean id="handlerMapping"
class="io.flysium.framework.web.servlet.mvc.method.annotation.CustomHandlerMapping">
<property name="order" value="-1" />
</bean>
CustomHandlerMapping實現:
@Override
protected RequestMappingInfo getMappingForMethod(Method method, Class handlerType) {
RequestMappingInfo info = createRequestMappingInfoDefault(method);
if (info != null) {
RequestMappingInfo typeInfo = createRequestMappingInfoDefault(handlerType);
if (typeInfo != null)
info = typeInfo.combine(info);
}
return info;
}
private RequestMappingInfo createRequestMappingInfoDefault(AnnotatedElement element) {
RequestMapping requestMapping = AnnotatedElementUtils.findMergedAnnotation(element,
RequestMapping.class);
RequestCondition condition = (element instanceof Class)
? getCustomTypeCondition((Class) element)
: getCustomMethodCondition((Method) element);
/**
* 以類名和方法名對映請求,參照@RequestMapping
* 預設不需要新增任何引數(如:/className/methodName.do)
*/
String defaultName = (element instanceof Class)
? ((Class) element).getSimpleName()
: ((Method) element).getName();
return requestMapping == null
? null
: createRequestMappingInfo(requestMapping, condition, defaultName);
}
protected RequestMappingInfo createRequestMappingInfo(RequestMapping annotation,
RequestCondition<?> customCondition, String defaultName) {
String[] patterns = resolveEmbeddedValuesInPatterns(annotation.value());
if (patterns != null && (patterns.length == 0)) {
patterns = new String[]{defaultName};
}
return new RequestMappingInfo(
new PatternsRequestCondition(patterns, getUrlPathHelper(), getPathMatcher(),
this.useSuffixPatternMatch, this.useTrailingSlashMatch,
this.fileExtensions),
new RequestMethodsRequestCondition(annotation.method()),
new ParamsRequestCondition(annotation.params()),
new HeadersRequestCondition(annotation.headers()),
new ConsumesRequestCondition(annotation.consumes(), annotation.headers()),
new ProducesRequestCondition(annotation.produces(), annotation.headers(),
this.contentNegotiationManager),
customCondition);
}
5)(必選)處理器介面卡(HandlerAdapter)配置,可以配置多個,主要是配置messageConverters,其主要作用是對映前臺傳參與handler處理方法引數。一般擴充套件RequestMappingHandlerAdapter,或者自定義。如果我們需要json請求的處理,這裡必須擴充套件。同時我們需要注意的是日期格式的轉換。
另外Spring 4.2新特性,加之註解會自動注入@ControllerAdvice,可以定義RequestBodyAdvice、ResponseBodyAdvice,可以更方便地在引數處理方面著手自定義。
<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">
<!-- 針對普通請求(非application/json) 前臺的日期字串與後臺的Java Date物件轉化,
此情況,應使用spring
mvc本身的內建日期處理 -->
<!-- 可以在VO屬性上加註解:@DateTimeFormat 需要類庫joda-time -->
<bean
class="org.springframework.format.support.FormattingConversionServiceFactoryBean">
</bean>
</property>
</bean>
</property>
</bean>
<!-- json請求(application/json)返回值Date轉String,全域性配置 -->
<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>
<!-- 如果想自定義,可以在VO屬性上加註解:@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執行Ajax時,返回JSON出現下載檔案 -->
<!-- 自定義 -->
<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)(可選)處理器異常解析器(HandlerExceptionResolver)配置,可以配置多個,配置Controller異常丟擲後,我們是怎麼樣處理的,一般需要日誌或做反饋的可以自定義。
7)(可選)請求到檢視名翻譯器(RequestToViewNameTranslator)配置,RequestToViewNameTranslator可以在處理器返回的View為空時使用它根據Request獲得viewName。
8)(可選)檢視解析器(ViewResolver)配置,可以配置多個,定義跳轉的檔案的前後綴 ,檢視模式配置,主要針對@Controller返回ModelAndView的檢視路徑解析,動給後面控制器的方法return的字串 加上字首和字尾,變成一個 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>
最後給Controller加入元件掃描吧,這樣減少xml配置,直接在Java程式碼中加入註解即可。
<!-- 自動掃描類包,將標誌Spring註解的類自動轉化為Bean,同時完成Bean的注入 -->
<!-- 掃描控制器 -->
<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,我們需要mybatis的jar包,及mybatis-spring整合jar包。然後在Spring容器中註冊配置org.mybatis.spring.SqlSessionFactoryBean(需要資料來源,及指定Mybatis配置檔案)及org.mybatis.spring.SqlSessionTemplate即可。
更多整合請參照Git專案:https://git.oschina.net/svenaugustus/app-ss4m-less
目前除了ssm,另外整合redis(支援切換單節點配置、主從哨兵配置,叢集配置)、spring session方案。
其中包括spring MVC的簡單demo,用於學習交流。