Measure Spring RestTemplate HTTP request time

You can use Stopwatch to do that.

public class PerfRequestSyncInterceptor implements ClientHttpRequestInterceptor {

    private final static Logger LOG = LoggerFactory.getLogger(PerfRequestSyncInterceptor.class);

    @Override
    public ClientHttpResponse intercept(HttpRequest hr, byte[] bytes, ClientHttpRequestExecution chre) throws IOException {
        StopWatch stopwatch = StopWatch.createStarted();
        ClientHttpResponse response = chre.execute(hr, bytes);
        stopwatch.stop();

        LOG.info("method=" + hr.getMethod() + ", uri="+hr.getURI() + ", response_time=" + stopwatch.elapsed(TimeUnit.MILLISECONDS) + ", response_code=" + response.getStatusCode().value());

        return response;
    }
}

And in the class where restTemplate is instanced

private final List<ClientHttpRequestInterceptor> requestInterceptors = new ArrayList<>();
requestInterceptors.add(new PerfRequestSyncInterceptor());
this.restTemplate.setInterceptors(requestInterceptors);

Add the Stopwatch dependency for maven:

<dependency>
  <groupId>com.google.guava</groupId>
  <artifactId>guava</artifactId>
  <version>r05</version>
</dependency>

You can use AOP and the built in PerformanceMonitorInterceptor of Spring. You need to correctly define which methods of which calss you want to intercept then you can measure. You can configure it something like this:

<?xml version="1.0" encoding="UTF-8"?>
<beans xmlns="http://www.springframework.org/schema/beans"
       xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
       xmlns:aop="http://www.springframework.org/schema/aop"
       xsi:schemaLocation="http://www.springframework.org/schema/beans      
        http://www.springframework.org/schema/beans/spring-beans-2.0.xsd
        http://www.springframework.org/schema/aop   
        http://www.springframework.org/schema/aop/spring-aop-2.0.xsd">
    <bean id="springMonitoredService"
        class="com.myorg.service.springmon.MyServiceSpringImpl"/>


    <bean id="springMonitoringAspectInterceptor"        
class="org.springframework.aop.interceptor.PerformanceMonitorInterceptor">
        <property name="loggerName"     
                value="com.myorg.SPRING_MONITOR"/>      
    </bean>


    <aop:config>
            <aop:pointcut id="springMonitoringPointcut"
                   expression="execution(* java.net.HttpURLConnection.connect(..))"/>




                <aop:advisor pointcut-ref="springMonitoringPointcut" 
            advice-ref="springMonitoringAspectInterceptor"/>      
    </aop:config>

</beans>