spring知识回顾

文章目录

1. 1. 拦截器利用了反射对请求进行自定义的操作可以访问action上下文和栈的对象，保证数据
2. 2. 过滤器利用原始servlet来进行操作主要可用于鉴权和
3. 3. AOP
4. 4. 不加载特定的bean
5. 5. stream 自定义function

spring的利用的面向切面编程（AOP），动态代理（反射）和filter，intercept，

ApplicationContent

Qualifier
Roucese
Autowired

拦截器利用了反射对请求进行自定义的操作可以访问action上下文和栈的对象，保证数据

@Component
public class MyInterceptor implements HandlerInterceptor {

    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {

        System.out.println("Interceptor 前置");
        return true;
    }

    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {

        System.out.println("Interceptor 处理中");
    }

    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {

        System.out.println("Interceptor 后置");
    }
}

过滤器利用原始servlet来进行操作主要可用于鉴权和

@Component
public class MyFilter implements Filter {
    
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

        System.out.println("Filter 前置");
    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {

        System.out.println("Filter 处理中");
        filterChain.doFilter(servletRequest, servletResponse);
    }

    @Override
    public void destroy() {

        System.out.println("Filter 后置");
    }
}

AOP

@Aspect
@Component
public class Aspect {
    @Pointcut("@annotation(com.HasAuth)")
    public void pointCut() {

    }

    @Around("pointCut()")
    public Object around(ProceedingJoinPoint point) throws Throwable {
        Object[] args = point.getArgs();
       /* if (StringUtil.IsEmpty(args[0])) {
            args[0] = "default";
        }*/
        return point.proceed(args);
    }
    //标注该方法体为后置通知，当目标方法执行成功后执行该方法体  
    @AfterReturning("within(com.abchina.irms..*) && @annotation(rl)")  
    public void addLogSuccess(JoinPoint jp, rmpfLog rl){  
        Object[] parames = jp.getArgs();//获取目标方法体参数  
        String params = parseParames(parames); //解析目标方法体的参数  
        String className = jp.getTarget().getClass().toString();//获取目标类名  
        className = className.substring(className.indexOf("com"));  
        String signature = jp.getSignature().toString();//获取目标方法签名  
        String methodName = signature.substring(signature.lastIndexOf(".")+1, signature.indexOf("("));  
        String modelName = getModelName(className); //根据类名获取所属的模块  
          
      ...
    }  
  
    //标注该方法体为异常通知，当目标方法出现异常时，执行该方法体  
    @AfterThrowing(pointcut="within(com.abchina.irms..*) && @annotation(rl)", throwing="ex")  
    public void addLog(JoinPoint jp, rmpfLog rl, BusinessException ex){  
       ...
    }  
}

不加载特定的bean

@Configuration @EnableSpringConfigured
@ComponentScan(basePackages = {"com.example"}, 
               excludeFilters={@ComponentScan.Filter(type = FilterType.REGEX, pattern = "org.xxx.yyy.*"),
  @ComponentScan.Filter(type=FilterType.ASSIGNABLE_TYPE, value=Foo.class)})
public class MySpringConfiguration {}

stream 自定义function