SpringBoot之拦截器与过滤器解读

public class MySelfInterceptor implements HandlerInterceptor {
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        System.out.println("在业务处理器处理请求之前被调用");
       //可以进行权限校验，安全控制
        MyRequestWrapper requestWrapper = new MyRequestWrapper (request);
        // 读取请求内容
        BufferedReader br = requestWrapper.getReader();
        String line = null;
        StringBuilder sb = new StringBuilder();
        while ((line = br.readLine()) != null) {
            sb.append(line);
        }
        // 将json字符串转换为json对象
        JSONObject body = JSONObject.parseObject(sb.toString());
        //业务处理
        return true;
    }
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        System.out.println("在业务处理器处理请求执行完成后，生成视图之前执行");
        //可以对返回来的ModelAndView进行处理，这个时候还未渲染视图
    }
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        System.out.println("在DispatcherServlet完全处理完请求后被调用");
        //请求已经完成，页面已经渲染，数据已经返回。这个时候可以做一些资源清理，或者记录请求调用时间，做性能监控
    }
}

@Component
public class MyInterceptor extends HandlerInterceptorAdapter {
    public SingleLoginInterceptor() {
        super();
    }
    @Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        return super.preHandle(request, response, handler);
    }
    @Override
    public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception {
        super.postHandle(request, response, handler, modelAndView);
    }
    @Override
    public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception {
        super.afterCompletion(request, response, handler, ex);
    }
    @Override
    public void afterConcurrentHandlingStarted(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        super.afterConcurrentHandlingStarted(request, response, handler);
    }
}

@Component
public class MyInterceptor implements WebRequestInterceptor {
    @Override
    public void preHandle(WebRequest webRequest) throws Exception {
    }
    @Override
    public void postHandle(WebRequest webRequest, ModelMap modelMap) throws Exception {
    }
    @Override
    public void afterCompletion(WebRequest webRequest, Exception e) throws Exception {
    }
}

@Configuration
public class CenterinsRequestInterceptor implements RequestInterceptor {
    @Override
    public void apply(RequestTemplate requestTemplate) {
    }
}

@Configuration
public class WebCofiguration extends WebMvcConfigurerAdapter {
     @Bean
	MyInterceptor getMyInterceptor (){
		return new MyInterceptor ();
	}
    public void addInterceptors(InterceptorRegistry registry) {
            // 将自己定义的拦截器注入进来进行拦截操作
        //registry.addInterceptor(new MySelfInterceptor ()) // 如果是new 出来的对象 会导致 拦截器中自动装配为空
       registry.addInterceptor(getMyInterceptor ())
                .addPathPatterns("/**")
                .excludePathPatterns("/logout");
                //过滤器可以添加多个，这里的addPathPatterns的/**是对所有的请求都做拦截。
                //excludePathPatterns代表排除url的拦截路径，即不拦截
    }
}

@Configuration
public class MyInterceptorConfig extends WebMvcConfigurationSupport {
    @Override
    protected void addInterceptors(InterceptorRegistry registry) {
        registry.addInterceptor(new MyInterceptor()).addPathPatterns("/**");
        super.addInterceptors(registry);
    }
}

@Override
protected void addResourceHandlers(ResourceHandlerRegistry registry) {
    registry.addResourceHandler("/**").addResourceLocations("classpath:/static/");
    super.addResourceHandlers(registry);
}

@Configuration
public class MyInterceptorConfig implements WebMvcConfigurer {
    @Override
    public void addInterceptors(InterceptorRegistry registry) {
        // 实现WebMvcConfigurer不会导致静态资源被拦截
        registry.addInterceptor(new MyInterceptor()).addPathPatterns("/**");
    }
}

import java.lang.annotation.ElementType;
import java.lang.annotation.Retention;
import java.lang.annotation.RetentionPolicy;
import java.lang.annotation.Target;
@Target(ElementType.METHOD)
@Retention(RetentionPolicy.RUNTIME)
public @interface LogData {
}

@LogData
public ResponseMessage getUserList(@RequestParam Long id) {
        return ResponseMessage.ok();
    }

@Override
    public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception {
        //这个方法将在请求处理之前进行调用。注意：如果该方法的返回值为false ，将视为当前请求结束，不仅自身的拦截器会失效，还会导致其他的拦截器也不再执行。
        log.info("进入到拦截器中:preHandle() 方法");
        HandlerMethod handlerMethod = (HandlerMethod) handler;
        LogData loginVerify = handlerMethod.getMethodAnnotation(LogData .class);
        if (loginVerify == null) {
            log.info("不需要对该路径 进行拦截");
            return true;
        }else {
            log.info("对该路径 进行拦截");
            log.info("业务操作...");
            return true;
        }
    }

 
import dm.jdbc.e.e;
import dm.jdbc.util.StreamUtil;
import edu.umd.cs.findbugs.annotations.SuppressFBWarnings;
import lombok.extern.slf4j.Slf4j;
import javax.servlet.ReadListener;
import javax.servlet.ServletInputStream;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletRequestWrapper;
import java.io.*;
import java.nio.charset.StandardCharsets;
/**
  * 重写 HttpServletRequestWrapper 
  * 
  */
@Slf4j
public class MyRequestWrapper extends HttpServletRequestWrapper {
	private byte[]  body; //用于保存读取body中数据
    public MyRequestWrapper (HttpServletRequest request) throws IOException {    
        super(request);
        //读取请求的数据保存到本类当中
        //body = StreamUtil.readBytes(request.getReader(), "UTF-8");
		StringBuilder stringBuilder = new StringBuilder();
		BufferedReader bufferedReader = null;
		InputStream inputStream = null;
		try{
			inputStream = request.getInputStream();
			if(inputStream != null){
				bufferedReader = new BufferedReader(new InputStreamReader(inputStream));
				char[] charBuffer = new char[128];
				int bytesRead =-1;
				while((bytesRead = bufferedReader.read(charBuffer)) >0){
					stringBuilder.append(charBuffer,0, bytesRead);
				}
			}else{
				stringBuilder.append("");
			}
		}catch (Exception e){
		}finally {
			if(inputStream != null){
				inputStream.close();
			}
			if(bufferedReader != null){
				bufferedReader.close();
			}
		}
		body = stringBuilder.toString().getBytes();
    }
    //覆盖（重写）父类的方法
    @SuppressFBWarnings("DM_DEFAULT_ENCODING")
	@Override
    public BufferedReader getReader() throws IOException {    
        return new BufferedReader(new InputStreamReader(getInputStream()));    
    }    
    //覆盖（重写）父类的方法
    @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() {
				// TODO Auto-generated method stub
				return false;
			}
			@Override
			public boolean isReady() {
				// TODO Auto-generated method stub
				return false;
			}
			@Override
			public void setReadListener(ReadListener arg0) {
				// TODO Auto-generated method stub
			} 
        };    
    }
    /**
     * 获取body中的数据
     * @return
     */
	public byte[] getBody() {
		return body;
	}
	/**
	 * 把处理后的参数放到body里面
	 * @param body
	 */
	public void setBody(byte[] body) {
		this.body = body;
	}
}

import lombok.extern.slf4j.Slf4j;
import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServletRequest;
import java.io.IOException;
/**
 * 过滤器
 * 
 */
@Slf4j
@WebFilter(urlPatterns = "/*", filterName = "logSignDataFilter")
public class LogSignDataFilter implements Filter {
	@Override
	public void destroy() {
	}
	@Override
    public void doFilter(ServletRequest request, ServletResponse response, FilterChain filterChain) throws IOException, ServletException {
		ServletRequest requestWrapper = null;
		if(request instanceof HttpServletRequest){
			requestWrapper = new MyRequestWrapper ((HttpServletRequest) request);
		}
		if(requestWrapper == null){
			filterChain.doFilter(request, response);
		}else{
			filterChain.doFilter(requestWrapper, response);
		}
    }
	@Override
	public void init(FilterConfig config) throws ServletException {
	}
}