使用servlet原生API作为参数

SpringMVC的Handler方法可以使用servlet原生的API作为目标方法的参数，具体支持以下类型：

* HttpServletRequest

* HttpServletResponse

* HttpSession

* java.security.Principal

* Locale InputStream

* OutputStream

* Reader

* Writer

此时，需要在pom.xml增加如下配置（别忘了版本<servlet-api.version>3.1.0</servlet-api.version>）：

<!-- servlet -->
        <dependency>
            <groupId>javax.servlet</groupId>
            <artifactId>javax.servlet-api</artifactId>
            <version>${servlet-api.version}</version>
            <scope>provided</scope>
        </dependency>

@RequestMapping("/springmvc")
@Controller
public class SpringMVCTest {
    private static final String SUCCESS = "success";
    @RequestMapping("/testServletAPI")
    public void testServletAPI(HttpServletRequest request,HttpServletResponse response,Writer out) throws IOException {
        System.out.println("testServletAPI," + request + "," + response);
        out.write("hello");
        //return SUCCESS;
    }

运行结果：

           在页面中会打印出hello  在console中：

           testServletAPI,org.apache.catalina.connector.RequestFacade@6dfcd74,org.apache.catalina.connector.ResponseFacade@fd25fbe