SpringBoot-@WebFilter使用

一、@WebFilter
用于将一个类声明为过滤器，在部署时被容器处理
常用属性：
filterName：指定过滤器的名字
urlPatterns：指定一组过滤器的URL匹配模式

二、示例

FilterOne.java

import java.io.IOException;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;

@WebFilter(filterName = "FilterOne", urlPatterns = { "/home/*" })
public class FilterOne implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("FilterOne过滤器初始化");
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest r = (HttpServletRequest)request;
        System.out.println("通过FilterOne过滤器，全路径：" + r.getRequestURL());
        chain.doFilter(request, response);
    }

    @Override
    public void destroy() {
    }
}

FilterTwo.java

import java.io.IOException;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;

@WebFilter(filterName = "FilterTwo", urlPatterns = { "/test/*" })
public class FilterTwo implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {
        System.out.println("FilterTwo过滤器初始化");
    }

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest r = (HttpServletRequest)request;
        System.out.println("通过FilterTwo过滤器，全路径：" + r.getRequestURL());
        chain.doFilter(request, response);
    }

    @Override
    public void destroy() {
    }
}

DemoApplication.java

import org.springframework.boot.SpringApplication;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.ServletComponentScan;

@SpringBootApplication
@ServletComponentScan
public class DemoApplication {
	public static void main(String[] args) {
		SpringApplication.run(DemoApplication.class, args);
	}
}

访问http://localhost:8080/home/1
执行结果

通过FilterOne过滤器，全路径：http://localhost:8080/home/1

访问http://localhost:8080/test/1
执行结果

通过FilterTwo过滤器，全路径：http://localhost:8080/test/1

注：看到过一个关于@webfilter的坑，使用@webfilter注解不上外部tomcat是没有问题的，如果上外部tomcat可能会踩到坑，可能会出现SpringBoot拦截器中Bean无法注入问题，还需实践