秒杀系统Web层主要涉及前端交互设计、Restful:url满足Restful设计规范、Spring MVC、bootstrap+jquery这四个方面的开发。秒杀系统的前端交互流程设计如下图6-3所示。
整合配置Spring MVC框架：
在web.xml中进行我们前端控制器DispatcherServlet的配置，配置springMVC需要加载的配置文件spring-dao.xml,spring-service.xml和spring-web.xml，详细配置如下。
web.xml：
<servlet>
<servlet-name>seckill-dispatcher</servlet-name>
<servlet-class>org.springframework.web.servlet.DispatcherServlet</servlet-class>
<init-param>
<param-name>contextConfigLocation</param-name>
<param-value>classpath:spring/spring-*.xml</param-value>
</init-param>
</servlet>
<servlet-mapping>
<servlet-name>seckill-dispatcher</servlet-name>
<url-pattern>/</url-pattern>
</servlet-mapping>
spring-web.xml：
<beans xmlns="http://www.springframework.org/schema/beans"
xmlns:xsi=http://www.w3.org/2001/XMLSchema-instance xmlns:mvc="http://www.springframework.org/schema/mvc"
xmlns:context="http://www.springframework.org/schema/context"
xsi:schemaLocation="http://www.springframework.org/schema/beans
http://www.springframework.org/schema/beans/spring-beans.xsd
http://www.springframework.org/schema/mvc
http://www.springframework.org/schema/mvc/spring-mvc.xsd
http://www.springframework.org/schema/context
http://www.springframework.org/schema/context/spring-context.xsd">
<mvc:annotation-driven/>
<mvc:default-servlet-handler/>
<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>
<context:component-scan base-package="org.seckill.web"/>
</beans>
完成Spring MVC的相关配置后，接下来就要基于Restful接口实现项目中的Controller开发。Controller中的每一个方法都对应我们系统中的一个资源URL，其设计应该遵循Restful接口的设计风格。在web包下创建一个SeckillController.java，内容如表6-11所示。
SeckillController.java：
@Controller
@RequestMapping("/seckill")
public class SeckillController {
private final Logger logger = LoggerFactory.getLogger(this.getClass());
@Autowired
private SeckillService seckillService;
@RequestMapping(value = "/list", method = RequestMethod.GET)
public String list(Model model) {
List<Seckill> list = seckillService.getSeckillList();
model.addAttribute("list", list);
//list.jsp + model = ModelAndView
return "list";
}
@RequestMapping(value = "/{seckillId}/detail", method = RequestMethod.GET)
public String detail(@PathVariable("seckillId") Long seckillId, Model model) {
if (seckillId == null) {
return "redirect:/seckill/list";
}
Seckill seckill = seckillService.getById(seckillId);
if (seckill == null) {
return "forward:/seckill/list";
}
model.addAttribute("seckill", seckill);
return "detail";
}
@RequestMapping(value = "/{seckillId}/exposer",
method = RequestMethod.POST,
produces = {"application/json;charset=UTF-8"})
@ResponseBody
public SeckillResult<Exposer> exposer(@PathVariable Long seckillId) {
SeckillResult<Exposer> result;
try {
Exposer exposer = seckillService.exportSeckillUrl(seckillId);
result = new SeckillResult<Exposer>(true, exposer);
} catch (Exception e) {
logger.error(e.getMessage(), e);
result = new SeckillResult<Exposer>(false, e.getMessage());
}
return result;
}
@RequestMapping(value = "/{seckillId}/{md5}/execution",
method = RequestMethod.POST,
produces = {"application/json;charset=UTF-8"})
@ResponseBody
public SeckillResult<SeckillExecution> execute(@PathVariable("seckillId") Long seckillId,
@PathVariable("md5") String md5,
@CookieValue(value = "killPhone", required = false) Long phone) {
//springmvc valid
if (phone == null) {
return new SeckillResult<SeckillExecution>(false, "未注册");
}
SeckillResult<SeckillExecution> result;
try {
SeckillExecution execution = seckillService.executeSeckillProcedure(seckillId, phone, md5);
return new SeckillResult<SeckillExecution>(true,execution);
} catch (RepeatKillException e) {
SeckillExecution execution = new SeckillExecution(seckillId, SeckillStatEnum.REPEAT_KILL);
return new SeckillResult<SeckillExecution>(true,execution);
} catch (SeckillCloseException e) {
SeckillExecution execution = new SeckillExecution(seckillId, SeckillStatEnum.END);
return new SeckillResult<SeckillExecution>(true,execution);
} catch (Exception e) {
logger.error(e.getMessage(), e);
SeckillExecution execution = new SeckillExecution(seckillId, SeckillStatEnum.INNER_ERROR);
return new SeckillResult<SeckillExecution>(true,execution);
}
}
@RequestMapping(value = "/time/now",method = RequestMethod.GET)
@ResponseBody
public SeckillResult<Long> time(){
Date now = new Date();
return new SeckillResult(true,now.getTime());
}
}
json数据的一个Vo类，即SeckillResult.java，在dto包中创建它，内容如下。
SeckillResult.java：
public class SeckillResult<T> {
private boolean success;
private T data;
private String error;
public SeckillResult(boolean success, T data) {
this.success = success;
this.data = data;
}
public SeckillResult(boolean success, String error) {
this.success = success;
this.error = error;
}
public boolean isSuccess() {
return success;
}
public void setSuccess(boolean success) {
this.success = success;
}
public T getData() {
return data;
}
public void setData(T data) {
this.data = data;
}
public String getError() {
return error;
}
public void setError(String error) {
this.error = error;
}
}