SpringBoot过滤器获取请求的参数

短命女 2024-04-24 14:51 62阅读 0赞

#### 一、背景 ####

在项目开发过程中，需要对于某些接口统一处理。  
这时候就需要获取请求的报文，再对获取的报文进行统一处理。

#### 二、了解过滤器 ####

首先了解一下过滤器拦截器的区别：  
[JAVA中的拦截器、过滤器：https://blog.csdn.net/qq\_38254635/article/details/131201519][JAVA_https_blog.csdn.net_qq_38254635_article_details_131201519]

#### 三、代码 ####

新建 WebRequestWrapper.java  
重写 HttpServletRequestWrapper，处理json报文请求

package com.config.filter;
    
    import java.io.BufferedReader;
    import java.io.ByteArrayInputStream;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import javax.servlet.ReadListener;
    import javax.servlet.ServletInputStream;
    import javax.servlet.http.HttpServletRequest;
    import javax.servlet.http.HttpServletRequestWrapper;
    import org.springframework.util.StreamUtils;
    
    public class WebRequestWrapper extends HttpServletRequestWrapper{
        
    
        private byte[] body;
    
        public WebRequestWrapper(HttpServletRequest request) throws IOException {
        
            super(request);
            body = StreamUtils.copyToByteArray(request.getInputStream());
        }
    
        @Override
        public BufferedReader getReader() throws IOException {
        
            return new BufferedReader(new InputStreamReader(getInputStream()));
        }
    
        @Override
        public ServletInputStream getInputStream() throws IOException {
        
            final ByteArrayInputStream bais = new ByteArrayInputStream(body);
            return new ServletInputStream() {
        
                @Override
                public int read() throws IOException {
        
                    return bais.read();
                }
                @Override
                public boolean isFinished() {
        
                    return false;
                }
    
                @Override
                public boolean isReady() {
        
                    return false;
                }
    
                @Override
                public void setReadListener(ReadListener listener) {
        
    
                }
            };
        }
    
        public byte[] getBody() {
        
            return body;
        }
    
        public void setBody(byte[] body) {
        
            this.body = body;
        }
    
    }

新建WebRequestFilter.java，请求过滤器处理参数，解密、字符串替、添加请求参数等等。

package com.config.filter;
    
    import java.io.BufferedReader;
    import java.io.IOException;
    import java.util.List;
    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.HttpServletRequest;
    import javax.servlet.http.HttpServletResponse;
    import com.Utils;
    import org.springframework.stereotype.Component;
    
    @Component
    public class WebRequestFilter implements Filter {
        
    
        @Override
        public void init(FilterConfig arg0) throws ServletException {
        
    
        }
    
        @Override
        public void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {
        
            HttpServletRequest httpRequest = (HttpServletRequest) request;
            HttpServletResponse httpResponse = (HttpServletResponse) response;
            if (checkPath(httpRequest.getRequestURI())) {
        
                chain.doFilter(request, response);
            } else {
        
                WebRequestWrapper requestWrapper = new WebRequestWrapper((HttpServletRequest) request);
                BufferedReader br = requestWrapper.getReader();
                String line = null;
                StringBuilder sb = new StringBuilder();
                while ((line = br.readLine()) != null) {
        
                    sb.append(line);
                }
                String original = sb.toString();
                String handle = Utils.handleRequest(original);
                requestWrapper.setBody(handle.getBytes("UTF-8"));
                chain.doFilter(requestWrapper, response);
            }
        }
    	
        private boolean checkPath(String url){
        
            if(!"on".equals(ENCRYPT_SWITCH)) return true;
            for (String path : REQUEST_LIST) {
        
                if(url.contains(path)) return true;
            }
            return false;
        }
    
        @Override
        public void destroy() {
        
    
        }
    
    }

说明：  
ENCRYPT\_SWITCH：开关配置  
REQUEST\_LIST：忽略处理路径配置，如一些导入的操作。  
Utils.handleRequest()：需要对报文进行的处理操作。

新建 WebRequestConfig.java 配置过滤器的执行顺序。  
order属性控制过滤器加载顺序：数字越小，加载越早

package com.config.filter;
    
    import org.springframework.boot.web.servlet.FilterRegistrationBean;
    import org.springframework.context.annotation.Bean;
    import org.springframework.context.annotation.Configuration;
    
    @Configuration
    public class WebRequestConfig {
        
        
        @Bean
        public FilterRegistrationBean ValidatorFilterRegistration() {
        
            FilterRegistrationBean<WebRequestFilter> registration = new FilterRegistrationBean<WebRequestFilter>();
            registration.setFilter(new WebRequestFilter());
            registration.addUrlPatterns("/*");
            registration.setOrder(Integer.MAX_VALUE-10);
            return registration;
        }
    }

相关链接：  
[SpringBoot过滤器获取响应的参数：https://blog.csdn.net/qq\_38254635/article/details/136041183][SpringBoot_https_blog.csdn.net_qq_38254635_article_details_136041183]  
[JAVA中的拦截器、过滤器：https://blog.csdn.net/qq\_38254635/article/details/131201519][JAVA_https_blog.csdn.net_qq_38254635_article_details_131201519]

OK，就这些吧。

有什么不对的还望指正，书写不易，觉得有帮助就点个赞吧！☺☺☺

参考链接:https://www.jb51.net/article/221072.html

[JAVA_https_blog.csdn.net_qq_38254635_article_details_131201519]: https://blog.csdn.net/qq_38254635/article/details/131201519
[SpringBoot_https_blog.csdn.net_qq_38254635_article_details_136041183]: https://blog.csdn.net/qq_38254635/article/details/136041183