下面是我的自定义Filter类的一个例子:

package com.dawson.controller.filter;

import org.springframework.stereotype.Component;
import org.springframework.web.filter.GenericFilterBean;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;


@Component
public class DawsonApiFilter extends GenericFilterBean {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) request;
        if (req.getHeader("x-dawson-nonce") == null || req.getHeader("x-dawson-signature") == null) {
            HttpServletResponse httpResponse = (HttpServletResponse) response;
            httpResponse.setContentType("application/json");
            httpResponse.sendError(HttpServletResponse.SC_BAD_REQUEST, "Required headers not specified in the request");
            return;
        }
        chain.doFilter(request, response);
    }
}

我将它添加到Spring Boot配置中，如下所示:

package com.dawson.configuration;

import com.fasterxml.jackson.datatype.hibernate5.Hibernate5Module;
import com.dawson.controller.filter.DawsonApiFilter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;

@SpringBootApplication
public class ApplicationConfiguration {
    @Bean
    public FilterRegistrationBean dawsonApiFilter() {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(new DawsonApiFilter());

        // In case you want the filter to apply to specific URL patterns only
        registration.addUrlPatterns("/dawson/*");
        return registration;
    }
}

如果您使用Spring Boot + Spring Security，则可以在安全配置中执行此操作。

在下面的示例中，我在UsernamePasswordAuthenticationFilter之前添加了一个自定义过滤器(请参阅所有默认的Spring安全过滤器及其顺序)。

@EnableWebSecurity
class SecurityConfig extends WebSecurityConfigurerAdapter {

    @Autowired FilterDependency filterDependency;

    @Override
    protected void configure(HttpSecurity http) throws Exception {
        http
            .addFilterBefore(
                new MyFilter(filterDependency),
                UsernamePasswordAuthenticationFilter.class);
    }
}

还有筛选器类

class MyFilter extends OncePerRequestFilter  {
    private final FilterDependency filterDependency;

    public MyFilter(FilterDependency filterDependency) {
        this.filterDependency = filterDependency;
    }

    @Override
    protected void doFilterInternal(HttpServletRequest request,
        HttpServletResponse response,
        FilterChain filterChain)
        throws ServletException, IOException {

        // Filter
        filterChain.doFilter(request, response);
    }
}

下面是一个在Spring Boot MVC应用程序中包含自定义过滤器的方法示例。确保在组件扫描中包含该包:

package com.dearheart.gtsc.filters;

import java.io.IOException;

import javax.servlet.Filter;
import javax.servlet.FilterChain;
import javax.servlet.FilterConfig;
import javax.servlet.ServletException;
import javax.servlet.ServletRequest;
import javax.servlet.ServletResponse;
import javax.servlet.http.HttpServletResponse;

import org.springframework.context.annotation.Profile;
import org.springframework.stereotype.Component;

@Component
public class XClacksOverhead implements Filter {

  public static final String X_CLACKS_OVERHEAD = "X-Clacks-Overhead";

  @Override
  public void doFilter(ServletRequest req, ServletResponse res,
      FilterChain chain) throws IOException, ServletException {

    HttpServletResponse response = (HttpServletResponse) res;
    response.setHeader(X_CLACKS_OVERHEAD, "GNU Terry Pratchett");
    chain.doFilter(req, res);
  }

  @Override
  public void destroy() {}

  @Override
  public void init(FilterConfig arg0) throws ServletException {}

}

步骤1:通过实现filter接口创建一个过滤器组件。

@Component
public class PerformanceFilter implements Filter {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain)
            throws IOException, ServletException {

        ...
        ...
    }

}

步骤2:使用FilterRegistrationBean将这个过滤器设置为URI模式。

@Configuration
public class FilterConfig {
    @Bean
    public FilterRegistrationBean<PerformanceFilter> perfFilter() {
        FilterRegistrationBean<PerformanceFilter> registration = new FilterRegistrationBean<>();
        registration.setFilter(new PerformanceFilter());
        registration.addUrlPatterns("/*");
        return registration;
    }
}

您可以参考此链接以获得完整的应用程序。

下面是我的自定义Filter类的一个例子:

package com.dawson.controller.filter;

import org.springframework.stereotype.Component;
import org.springframework.web.filter.GenericFilterBean;

import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;


@Component
public class DawsonApiFilter extends GenericFilterBean {

    @Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        HttpServletRequest req = (HttpServletRequest) request;
        if (req.getHeader("x-dawson-nonce") == null || req.getHeader("x-dawson-signature") == null) {
            HttpServletResponse httpResponse = (HttpServletResponse) response;
            httpResponse.setContentType("application/json");
            httpResponse.sendError(HttpServletResponse.SC_BAD_REQUEST, "Required headers not specified in the request");
            return;
        }
        chain.doFilter(request, response);
    }
}

我将它添加到Spring Boot配置中，如下所示:

package com.dawson.configuration;

import com.fasterxml.jackson.datatype.hibernate5.Hibernate5Module;
import com.dawson.controller.filter.DawsonApiFilter;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.boot.autoconfigure.SpringBootApplication;
import org.springframework.boot.web.servlet.FilterRegistrationBean;
import org.springframework.context.annotation.Bean;
import org.springframework.http.converter.json.Jackson2ObjectMapperBuilder;

@SpringBootApplication
public class ApplicationConfiguration {
    @Bean
    public FilterRegistrationBean dawsonApiFilter() {
        FilterRegistrationBean registration = new FilterRegistrationBean();
        registration.setFilter(new DawsonApiFilter());

        // In case you want the filter to apply to specific URL patterns only
        registration.addUrlPatterns("/dawson/*");
        return registration;
    }
}

用一个Spring原型(如@Component)注释你的过滤器。在Spring @Configuration中注册一个Filter类型的@Bean。在Spring @Configuration中用FilterRegistrationBean类型注册一个@Bean。