利用Spring MVC 的 Interceptor 实现个简易的性能监控，计算一下每个url的执行时间。

在 preHandle 方法中记录当前的时间戳到线程局部变量里，然后在afterCompletion方法中，用当前的时间戳剪掉线程局部变量里的时间戳得出个运行时间，并记录到log里。

这只是个简易的性能监控，如果想长期正式的监控性能，请选择其它成熟的产品。

Interceptor

import javax.servlet.http.HttpServletRequest;import javax.servlet.http.HttpServletResponse; import org.slf4j.Logger;import org.slf4j.LoggerFactory;import org.springframework.core.NamedThreadLocal;import org.springframework.web.servlet.HandlerInterceptor;import org.springframework.web.servlet.ModelAndView; public class PerformanceInterceptor implements HandlerInterceptor { private final static Logger LOGGER = LoggerFactory.getLogger(PerformanceInterceptor.class); private NamedThreadLocal<Long> startTimeThreadLocal = new NamedThreadLocal<Long>("performance"); @Override public boolean preHandle(HttpServletRequest request, HttpServletResponse response, Object handler) throws Exception { startTimeThreadLocal.set(System.currentTimeMillis()); return true; } @Override public void postHandle(HttpServletRequest request, HttpServletResponse response, Object handler, ModelAndView modelAndView) throws Exception { return; } @Override public void afterCompletion(HttpServletRequest request, HttpServletResponse response, Object handler, Exception ex) throws Exception { long currentTime = System.currentTimeMillis(); long executeTime = currentTime - startTimeThreadLocal.get(); LOGGER.info("uri：{} 执行了 {} 毫秒", request.getRequestURI(), executeTime); } }

这里的是NamedThreadLocal没啥神器的，源码如下：

package org.springframework.core; import org.springframework.util.Assert; public class NamedThreadLocal<T> extends ThreadLocal<T> { private final String name; public NamedThreadLocal(String name) { Assert.hasText(name, "Name must not be empty"); this.name = name; } @Override public String toString() { return this.name; } }

定义完Interceptor，注册即可。

import java.util.List; import org.springframework.boot.autoconfigure.condition.ConditionalOnMissingBean;import org.springframework.boot.web.filter.OrderedCharacterEncodingFilter;import org.springframework.context.annotation.Bean;import org.springframework.context.annotation.Configuration;import org.springframework.http.converter.HttpMessageConverter;import org.springframework.web.filter.CharacterEncodingFilter;import org.springframework.web.servlet.config.annotation.InterceptorRegistry;import org.springframework.web.servlet.config.annotation.ResourceHandlerRegistry;import org.springframework.web.servlet.config.annotation.ViewControllerRegistry;import org.springframework.web.servlet.config.annotation.WebMvcConfigurerAdapter; import com.vnierlai.scm.webapp.interceptor.PerformanceInterceptor; @Configurationpublic class WebMvcConfigurer extends WebMvcConfigurerAdapter { @Bean @ConditionalOnMissingBean(CharacterEncodingFilter.class) public CharacterEncodingFilter characterEncodingFilter() { CharacterEncodingFilter filter = new OrderedCharacterEncodingFilter(); filter.setEncoding("UTF-8"); return filter; } @Override public void addInterceptors(InterceptorRegistry registry) { registry.addInterceptor(new PerformanceInterceptor()).addPathPatterns("/**"); super.addInterceptors(registry); } @Override public void addResourceHandlers(ResourceHandlerRegistry registry) { registry.addResourceHandler("/webjars/**").addResourceLocations("classpath:/META-INF/resources/webjars/"); // registry.addResourceHandler("/resources/**").addResourceLocations("/resources/"); } }

以上就是本文的全部内容，希望对大家的学习有所帮助，也希望大家多多支持。