Spring MVC Interceptor functional code for performance monitoring

Using Interceptor of Spring MVC to realize a simple performance monitoring, calculate the execution time of each url under 1.

Record the current timestamp into the thread local variable in the preHandle method, and then cut the timestamp in the thread local variable in the afterCompletion method with the current timestamp to get the run time and record it in log.

This is just a simple performance monitoring, if you want to formally monitor performance for a long time, please choose other mature products.

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 : {}  To perform the  {}  ms ", request.getRequestURI(), executeTime);
  }
 
}

Here is NamedThreadLocal without any artifact, the source code is as follows:

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;
  }
 
}

After defining Interceptor, register.

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;
 
@Configuration
public 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/");
  }
 
}