过滤器()-其他
过滤器()
使用过滤器，首先需要实现过滤器的三个方法：init()，doFilter()，destroy()
1 package com.dayee.gateway.filter;
2
3 import lombok.extern.slf4j.Slf4j;
4 import org.springframework.core.annotation.Order;
5 import org.springframework.stereotype.Component;
6
7 import javax.servlet.*;
8 import javax.servlet.annotation.WebFilter;
9 import javax.servlet.http.HttpServletRequest;
10 import javax.servlet.http.HttpServletRequestWrapper;
11 import javax.servlet.http.HttpServletResponse;
12 import javax.servlet.http.HttpServletResponseWrapper;
13 import java.io.IOException;
14
15 /**
16 * @Author OuYangFL
17 * @Date 2022/8/5 4:26 下午
18 */
19 @Component // 如果是用该注解，则CommonFilter过滤器类已经被注入到Spring容器中进行管理，不需要再添加过滤器配置类
20 @Slf4j
21 public class CommonFilter implements Filter {
22 @Override
23 public void init(FilterConfig filterConfig) throws ServletException {
24 log.info("初始化过滤器init");
25 }
26
27 @Override
28 public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
29 HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;
30 HttpServletResponseWrapper httpServletResponseWrapper = new HttpServletResponseWrapper((HttpServletResponse) servletResponse);
31 String requestURI = httpServletRequest.getRequestURI();
32 log.info(String.format("请求地址URI：%s", requestURI));
33 log.info("没有权限访问，跳转到index");
34 servletRequest.getRequestDispatcher("/index").forward(servletRequest, servletResponse);
35 /**if (requestURI.contains("/3")){
36 filterChain.doFilter(servletRequest, servletResponse);
37
38 }else {
39 log.info("没有权限访问，跳转到index");
40 //httpServletResponseWrapper.sendRedirect("/");
41 servletRequest.getRequestDispatcher("/index").forward(servletRequest, servletResponse);
42 }*/
43 }
44
45 @Override
46 public void destroy() {
47 log.info("过滤器被销毁");
48 }
49 }编写过滤器配置类，用来加载过滤器类CommonFilter（在过滤器类没有添加@Component注解时）
1 package com.dayee.gateway.config;
2
3 import com.dayee.gateway.filter.CommonFilter;
4 import org.springframework.beans.factory.annotation.Autowired;
5 import org.springframework.boot.web.servlet.FilterRegistrationBean;
6 import org.springframework.context.annotation.Bean;
7 import org.springframework.context.annotation.Configuration;
8 import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
9
10 /**
11 * @Author OuYangFL
12 * @Date 2022/8/6 9:47 上午
13 */
14
15 @Configuration
16 public class FilterConfig implements WebMvcConfigurer {
17
18
19 @Bean
20 public FilterRegistrationBean filterRegistrationBean(){
21 FilterRegistrationBean filterRegistration = new FilterRegistrationBean(new CommonFilter());
22 //filterRegistration.setFilter(new CommonFilter());
23 filterRegistration.addUrlPatterns("/1");
24 filterRegistration.setName("select");
25 filterRegistration.setOrder(1);
26 return filterRegistration;
27 }
28 }如果是用配置类与过滤器类相结合使用，在FilterConfig中addUrlPatterns方法可以进行URL拦截等相关设置
如果不使用配置类进行加载过滤器，直接使用@Component注解将过滤器类交给Spring容器，那么对URL的拦截设置可以在doFilter方法中进行创建。
暂时理解程度到此，后续研究继续深入
————————
使用过滤器，首先需要实现过滤器的三个方法：init()，doFilter()，destroy()
1 package com.dayee.gateway.filter;
2
3 import lombok.extern.slf4j.Slf4j;
4 import org.springframework.core.annotation.Order;
5 import org.springframework.stereotype.Component;
6
7 import javax.servlet.*;
8 import javax.servlet.annotation.WebFilter;
9 import javax.servlet.http.HttpServletRequest;
10 import javax.servlet.http.HttpServletRequestWrapper;
11 import javax.servlet.http.HttpServletResponse;
12 import javax.servlet.http.HttpServletResponseWrapper;
13 import java.io.IOException;
14
15 /**
16 * @Author OuYangFL
17 * @Date 2022/8/5 4:26 下午
18 */
19 @Component // 如果是用该注解，则CommonFilter过滤器类已经被注入到Spring容器中进行管理，不需要再添加过滤器配置类
20 @Slf4j
21 public class CommonFilter implements Filter {
22 @Override
23 public void init(FilterConfig filterConfig) throws ServletException {
24 log.info("初始化过滤器init");
25 }
26
27 @Override
28 public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
29 HttpServletRequest httpServletRequest = (HttpServletRequest) servletRequest;
30 HttpServletResponseWrapper httpServletResponseWrapper = new HttpServletResponseWrapper((HttpServletResponse) servletResponse);
31 String requestURI = httpServletRequest.getRequestURI();
32 log.info(String.format("请求地址URI：%s", requestURI));
33 log.info("没有权限访问，跳转到index");
34 servletRequest.getRequestDispatcher("/index").forward(servletRequest, servletResponse);
35 /**if (requestURI.contains("/3")){
36 filterChain.doFilter(servletRequest, servletResponse);
37
38 }else {
39 log.info("没有权限访问，跳转到index");
40 //httpServletResponseWrapper.sendRedirect("/");
41 servletRequest.getRequestDispatcher("/index").forward(servletRequest, servletResponse);
42 }*/
43 }
44
45 @Override
46 public void destroy() {
47 log.info("过滤器被销毁");
48 }
49 }编写过滤器配置类，用来加载过滤器类CommonFilter（在过滤器类没有添加@Component注解时）
1 package com.dayee.gateway.config;
2
3 import com.dayee.gateway.filter.CommonFilter;
4 import org.springframework.beans.factory.annotation.Autowired;
5 import org.springframework.boot.web.servlet.FilterRegistrationBean;
6 import org.springframework.context.annotation.Bean;
7 import org.springframework.context.annotation.Configuration;
8 import org.springframework.web.servlet.config.annotation.WebMvcConfigurer;
9
10 /**
11 * @Author OuYangFL
12 * @Date 2022/8/6 9:47 上午
13 */
14
15 @Configuration
16 public class FilterConfig implements WebMvcConfigurer {
17
18
19 @Bean
20 public FilterRegistrationBean filterRegistrationBean(){
21 FilterRegistrationBean filterRegistration = new FilterRegistrationBean(new CommonFilter());
22 //filterRegistration.setFilter(new CommonFilter());
23 filterRegistration.addUrlPatterns("/1");
24 filterRegistration.setName("select");
25 filterRegistration.setOrder(1);
26 return filterRegistration;
27 }
28 }如果是用配置类与过滤器类相结合使用，在FilterConfig中addUrlPatterns方法可以进行URL拦截等相关设置
如果不使用配置类进行加载过滤器，直接使用@Component注解将过滤器类交给Spring容器，那么对URL的拦截设置可以在doFilter方法中进行创建。
暂时理解程度到此，后续研究继续深入