【Java】 SpringBoot + Servlet 3.0 注解使用笔记

spring-boot 2.11
JSR-000315 Java Servlet3.0规范

Servlet3.0与Servlet2.5的区别

  • 异步处理支持
  • 新增的注解支持
  • 可拔插性支持

@WebServlet、@WebFilter、@WebListener

@WebServlet, @WebFilter, and @WebListener annotated classes can be automatically registered with an embedded servlet container by annotating a @Configuration class with @ServletComponentScan and specifying the package(s) containing the components that you want to register. By default, @ServletComponentScan scans from the package of the annotated class.

ServletConfig

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@Configuration
@ServletComponentScan
public class ServletConfig {}

@WebServlet

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@WebServlet(name = "hello", 
urlPatterns = {"/hello"}, 
loadOnStartup = 1, 
description = "this is a test")
public class TestServlet extends HttpServlet {}

@WebFilter

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/**
 * Filter的执行顺序为类名匹配 A-Z
 * AFilter 比 BFilter先执行
 */
@WebFilter(filterName = "testFilter"
,urlPatterns = "/*")
public class TestFilter implements Filter {}

@WebListener

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/**
 * Request:
 * ServletRequestListener : 监听Request的创建和销毁
 * ServletRequestAttributeListener : 监听Request的属性,新增属性、移除属性和属性值被替换时
 *
 * Session:
 * HttpSessionListener : 监听HttpSession的创建跟销毁
 * HttpSessionAttributeListener : 监听session中属性,新增属性、移除属性和属性值被替换时
 *
 * ServletContext:
 * ServletContextListener : 监听ServletContext的创建和销毁
 * ServletContextAttributeListener : 监听ServletContext中属性的新增、移除和属性值的替换
 */
@WebListener
public class TestRequestListener implements ServletRequestListener {}