首先来看一下@RequestMapping这个注解

public @interface RequestMapping {/**方法要拦截的url集合*/String[] value() default {};/**url访问的方法集合*/RequestMethod[] method() default {};}

看一下下面的例子

@RequestMapping(value = {"/listRole", "/listRole2"}, method = {RequestMethod.GET, RequestMethod.POST})
public List<Role> listRole() {return ...;
}

上面的例子表示以下的访问链接都将访问listRole()这个方法，需要注意的是：如果没有配置method，那么所有访问的Request Method类型都将满足。

springmvc中将@RequestMapping解析为org.springframework.web.servlet.mvc.method.RequestMappingInfo，对应的方法信息存在org.springframework.web.method.HandlerMethod中，通过org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping可以获取到所有RequestMappingInfo以及对应的HandlerMethod。

通过下面的代码来分析

import com.alibaba.fastjson.JSON;
import com.alibaba.fastjson.JSONArray;
import com.alibaba.fastjson.JSONObject;
import com.eduboss.annotations.AliyunLogFilterIgnore;
import com.eduboss.domain.User;
import com.eduboss.dto.DataPackage;
import com.eduboss.dto.DataPackageForJqGrid;
import com.eduboss.logger.LoggerHelper;
import com.eduboss.logger.WapperedResponse;
import com.eduboss.service.UserService;
import com.eduboss.utils.AliyunSLSUtils;
import com.eduboss.utils.PropertiesUtils;
import com.eduboss.utils.StringUtil;
import com.google.common.collect.Maps;
import org.apache.commons.lang3.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.BeanFactoryUtils;
import org.springframework.core.annotation.AnnotationUtils;
import org.springframework.util.AntPathMatcher;
import org.springframework.web.bind.annotation.RequestMethod;
import org.springframework.web.context.ContextLoader;
import org.springframework.web.context.WebApplicationContext;
import org.springframework.web.method.HandlerMethod;
import org.springframework.web.servlet.HandlerMapping;
import org.springframework.web.servlet.mvc.condition.PatternsRequestCondition;
import org.springframework.web.servlet.mvc.condition.RequestMethodsRequestCondition;
import org.springframework.web.servlet.mvc.method.RequestMappingInfo;
import org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerMapping;import javax.servlet.*;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;
import java.lang.reflect.Method;
import java.util.*;
import java.util.concurrent.ConcurrentHashMap;public class AliyunLogFilter implements Filter {private static final Logger log = LoggerFactory.getLogger(AliyunLogFilter.class);private Map<String, Map<String, RequestToMethodItem>> urlControllerMappings = new HashMap<>(1024);private ThreadLocal<Long> startTimeHolder = new ThreadLocal<>();private ThreadLocal<Long> endTimeHolder = new ThreadLocal<>();private static final String ALL_METHOD_TYPE = "[]";//系统中访问的url后缀，一般controller没有配置，需要去除private static final String[] suffixs = new String[]{".do"};@Overridepublic void init(FilterConfig filterConfig) throws ServletException {loadUrlControllerMappings(filterConfig);}//加载url对应的controller信息private void loadUrlControllerMappings(FilterConfig filterConfig) {String contextPath = filterConfig.getServletContext().getContextPath();WebApplicationContext webApplicationContext = ContextLoader.getCurrentWebApplicationContext();//获取所有的RequestMappingMap<String, HandlerMapping> allRequestHandlerMappings = BeanFactoryUtils.beansOfTypeIncludingAncestors(webApplicationContext, HandlerMapping.class, true, false);for (HandlerMapping handlerMapping : allRequestHandlerMappings.values()) {//这里只需要RequestMappingHandlerMapping中的URL映射if (handlerMapping instanceof RequestMappingHandlerMapping) {RequestMappingHandlerMapping requestMappingHandlerMapping = (RequestMappingHandlerMapping) handlerMapping;Map<RequestMappingInfo, HandlerMethod> handlerMethods = requestMappingHandlerMapping.getHandlerMethods();for (Map.Entry<RequestMappingInfo, HandlerMethod> requestMappingInfoHandlerMethodEntry : handlerMethods.entrySet()) {RequestMappingInfo requestMappingInfo = requestMappingInfoHandlerMethodEntry.getKey();HandlerMethod mappingInfoValue = requestMappingInfoHandlerMethodEntry.getValue();RequestMethodsRequestCondition methodCondition = requestMappingInfo.getMethodsCondition();//url可以访问的method类型Set<RequestMethod> methods = methodCondition.getMethods();Set<String> requestMethodNames = new HashSet<>();methods.forEach(e -> requestMethodNames.add(e.name().toUpperCase()));PatternsRequestCondition patternsCondition = requestMappingInfo.getPatternsCondition();//可以访问的urlSet<String> urlPatterns = patternsCondition.getPatterns();Class<?> controllerClass = mappingInfoValue.getBeanType();Method controllerMethod = mappingInfoValue.getMethod();Class<?>[] methodParamTypes = mappingInfoValue.getMethod().getParameterTypes();Class<?> requestType = mappingInfoValue.getMethod().getReturnType();for (String url : urlPatterns) {url = contextPath + url;Map<String, RequestToMethodItem> mappings = urlControllerMappings.get(url);if (mappings == null) {mappings = new HashMap<>();urlControllerMappings.put(url, mappings);}if (requestMethodNames.isEmpty()) {//如果为空，说明所有method类型都可以访问mappings.put(ALL_METHOD_TYPE, new RequestToMethodItem(url, ALL_METHOD_TYPE, controllerClass, controllerMethod, methodParamTypes, requestType));} else {for (String mName : requestMethodNames) {mappings.put(mName, new RequestToMethodItem(url, mName, controllerClass, controllerMethod, methodParamTypes, requestType));}}}}}}}@Overridepublic void doFilter(ServletRequest request, ServletResponse response, FilterChain chain) throws IOException, ServletException {HttpServletRequest httpServletRequest = (HttpServletRequest) request;HttpServletResponse httpServletResponse = (HttpServletResponse) response;startTimeHolder.set(System.currentTimeMillis());chain.doFilter(httpServletRequest, httpServletResponse);endTimeHolder.set(System.currentTimeMillis());addLog(httpServletRequest, httpServletResponse);}private void addLog(HttpServletRequest request, HttpServletResponse response) {Map<String, String> contents = Maps.newLinkedHashMap();setRequestInfo(request, contents);setControllerInfo(request, response, contents);setResponseInfo(response, contents);log.info(contents.toString());//可以根据自己的需要进行记录}private void setResponseInfo(HttpServletResponse response, Map<String, String> contents) {contents.put("startTime", startTimeHolder.get().toString());contents.put("endTime", endTimeHolder.get().toString());contents.put("consumedTime", (endTimeHolder.get() - startTimeHolder.get()) + "");contents.put("status", response.getStatus() + "");}//这里是设置用户的访问信息private void setRequestInfo(HttpServletRequest request, Map<String, String> contents) {String uri = request.getRequestURI();String method = request.getMethod().toUpperCase();String remoteHost = request.getRemoteHost();String sessionId = request.getSession().getId();StringBuilder params = new StringBuilder();Enumeration<String> keys = request.getParameterNames();while (keys.hasMoreElements()) {String k = keys.nextElement();String[] v = request.getParameterValues(k);if (params.length() == 0) {params.append("{");} else {params.append(",");}params.append(k).append("=");if (v.length == 1) {params.append(v[0]);} else {params.append(Arrays.toString(v));}}if (params.length() > 0) {params.append("}");} else {params.append("{}");}contents.put("requestUri", uri);contents.put("requestMethod", method);contents.put("remoteHost", remoteHost);contents.put("sessionId", sessionId);contents.put("params", params.toString());}private void setControllerInfo(HttpServletRequest request, HttpServletResponse response, Map<String, String> contents) {String uri = request.getRequestURI();String method = request.getMethod().toUpperCase();//去掉后缀uri = removeSuffix(uri);String path = getAntPathMatchUrl(uri, urlControllerMappings.keySet());Map<String, RequestToMethodItem> requestToMethodItems = urlControllerMappings.get(path);RequestToMethodItem item = null;if (requestToMethodItems != null) {item = requestToMethodItems.get(ALL_METHOD_TYPE);if (item == null) {item = requestToMethodItems.get(method);}}if (item != null) {contents.put("controllerClassName", item.controllerClassName);contents.put("controllerMethodName", item.controllerMethodName);contents.put("controllerMethodParameterTypeNames", item.methodParmaTypesName);contents.put("controllerMethodReturnTypeName", item.returnTypeName);}}private String getAntPathMatchUrl(String uri, Set<String> patternUrls) {if (patternUrls.contains(uri)) {return uri;}String path = null;//通配判断AntPathMatcher matcher = new AntPathMatcher();for (String pt : patternUrls) {if (matcher.match(pt, uri)) {path = pt;break;}}return path;}private String removeSuffix(String uri) {for (String sf : suffixs) {if (uri.endsWith(sf)) {uri = uri.substring(0, uri.length() - sf.length());break;}}return uri;}@Overridepublic void destroy() {}private class RequestToMethodItem {String requestUrl;String requestMethod;Class<?> controllerClass;Method controllerMethod;Class<?>[] methodParmaTypes;Class<?> returnType;String controllerClassName;String controllerMethodName;String methodParmaTypesName;String returnTypeName;public RequestToMethodItem(String requestUrl, String requestMethods, Class<?> controllerClass, Method controllerMethod, Class<?>[] methodParmaTypes, Class<?> returnType) {this.requestUrl = requestUrl;this.requestMethod = requestMethods;this.controllerClass = controllerClass;this.controllerMethod = controllerMethod;this.methodParmaTypes = methodParmaTypes;this.returnType = returnType;this.controllerClassName = controllerClass.getName();this.controllerMethodName = controllerMethod.getName();if (returnType != null) {returnTypeName = returnType.getName();} else {returnTypeName = Void.class.getName();}methodParmaTypesName = Arrays.toString(methodParmaTypes);}@Overridepublic String toString() {return "requestUrl: " + requestUrl + ", requestMethod: " + requestMethod + ", controllerClassName: " + controllerClassName + ", controllerMethodName: " + controllerMethodName+ ", methodParmaTypes: " + methodParmaTypesName + ", returnType: " + returnTypeName;}}}