Use @WebFilter a comment

@WebFilter written on the class

@WebFilter common attributes

Filter Implementation

Javax.servlet.Filter write filter class implements an interface, plus @WebFilter notes, can not set the filter execution order

package com.jsong.wiki.blog.filter;

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

@WebFilter(filterName = "testfilter",urlPatterns ={"/blog/*"})
public class AnnotatedRequestFitler implements Filter {

    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.printf("filter");
        filterChain.doFilter(servletRequest,servletResponse);
    }

    @Override
    public void destroy() {

    }
}

@ServletComponentScan added in the configuration class has @Configuration also be directly added to the starting class

@ServletComponentScan not automatically scan the default packet where the current class parameter, the packet may be designated scan

package com.jsong.wiki.blog.filter;

import org.springframework.boot.web.servlet.ServletComponentScan;
import org.springframework.context.annotation.Configuration;

@ServletComponentScan(value = "com.jsong.wiki.blog.filter")
@Configuration
public class TestConfig {
}

Filter configured, when accessing http: // localhost: When 8080 / blog / test, the console will be printed filter

Two configuration Bean

Write a filter class that implements the interface javax.servlet.Filter

package com.jsong.wiki.blog.filter;

import org.springframework.stereotype.Component;

import javax.servlet.*;
import java.io.IOException;

public class RequestFilter implements Filter {


    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.printf("hello");
        filterChain.doFilter(servletRequest, servletResponse);
    }

    @Override
    public void destroy() {

    }
}

In the bean configuration instantiate this class Filter

package com.jsong.wiki.blog.config;

import com.jsong.wiki.blog.filter.RequestFilter;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.servlet.Filter;

@Configuration
public class FilterConfig {

    @Bean
    public Filter registerRequestFilter() {
        return new RequestFilter();
    }
}

Three FilterRegistrationBean (recommended), you can configure the filter order

And about the same way, first create a filter class that implements the interface javax.servlet.Filter
Note To write a comment on @Component class, this class to container-managed

package com.jsong.wiki.blog.filter;

import org.springframework.stereotype.Component;

import javax.servlet.*;
import java.io.IOException;

@Component
public class RequestFilter implements Filter {


    @Override
    public void init(FilterConfig filterConfig) throws ServletException {

    }

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        System.out.printf("hello");
        filterChain.doFilter(servletRequest, servletResponse);
    }

    @Override
    public void destroy() {

    }
}

In the configuration class by the filter management FilterRegistrationBean

package com.jsong.wiki.blog.config;

import com.jsong.wiki.blog.filter.RequestFilter;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.context.annotation.Configuration;

import javax.servlet.Filter;

@Configuration
public class FilterConfig {

//    @Bean
//    public Filter registerRequestFilter() {
//        return new RequestFilter();
//    }

    @Bean
    public FilterRegistrationBean registration(RequestFilter filter) {
        FilterRegistrationBean bean = new FilterRegistrationBean(filter);
        bean.addUrlPatterns("/blog/*");
        // 排序
        bean.setOrder(1);
        return bean;
    }
}