springboot Actual Warfare Registered filter s and listener s

Posted by PeeJay on Thu, 16 Jul 2020 17:00:45 +0200

Application Scenarios

There are special processes in your project that require filters and listeners, such as the spring Framework Character Filter CahracterEncoding Filter.

code implementation

MyFilter.java

@WebFilter(urlPatterns = "/*",description = "custom filter")
public class MyFilter implements Filter {
    private final Logger _logger = LoggerFactory.getLogger(this.getClass());
    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        _logger.info("MyFilter init ...");
    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        _logger.info("Handle filter business ...");
        filterChain.doFilter(servletRequest,servletResponse);
    }

    @Override
    public void destroy() {
        _logger.info("MyFilter destroy ...");
    }
}

MyListener.java

@WebListener
public class MyListener implements ServletContextListener {
    private final Logger _logger = LoggerFactory.getLogger(this.getClass()) ;
    @Override
    public void contextInitialized(ServletContextEvent servletContextEvent) {
        _logger.info("contextInitialized");
        _logger.info(servletContextEvent.getServletContext().getContextPath());
    }
    @Override
    public void contextDestroyed(ServletContextEvent servletContextEvent) {
        _logger.info("contextDestroyed");
    }
}

Program Entry SpringBootFilterListenerApplication.java

@SpringBootApplication
@ServletComponentScan({
        "com.hsy.springboot.filter.listener.filter",
        "com.hsy.springboot.filter.listener.listener"
})
public class SpringBootFilterListenerApplication {
    public static void main(String[] args) {
        SpringApplication.run(SpringBootFilterListenerApplication.class,args);
    }
}