JAVA Metrics 度量工具使用介绍1

Java Metric使用介绍1

Metrics是一个给JAVA提供度量工具的包，在JAVA代码中嵌入Metrics代码，可以方便的对业务代码的各个指标进行监控，同一时候，Metrics可以非常好的跟Ganlia、Graphite结合，方便的提供图形化接口。

以下简介下Metrics怎样使用。

Maven地址：

仅仅须要添加�metrics-core就可以使用

<dependency>

        <groupId>com.yammer.metrics</groupId>

        <artifactId>metrics-core</artifactId>

        <version>2.2.0</version>

    </dependency>

源文档 <http://metrics.codahale.com/getting-started/>

以下通过一些測试代码介绍Metrics每一个组件的使用，比較简单，基本看代码就懂了，这里不做过多介绍，请结合http://metrics.codahale.com/getting-started/介绍一起看，这里相当于完好代码。

Gauges

最简单的度量指标，每次相当于重置这个值。

package com.alibaba.cxf.test.metric;

import java.util.LinkedList;
import java.util.Queue;
import java.util.concurrent.TimeUnit;

import com.yammer.metrics.Metrics;
import com.yammer.metrics.core.Counter;
import com.yammer.metrics.core.Gauge;
import com.yammer.metrics.reporting.ConsoleReporter;

/**
 * TODO
 * @author scutshuxue.chenxf
 */
public class TestGauges {
        public static Queue<String> queue = new LinkedList<String>();

        public static void main(String[] args) throws InterruptedException{
               ConsoleReporter.enable(5,TimeUnit.SECONDS);

               Gauge<Integer>g = Metrics.newGauge(TestGauges.class, "pending-jobs", newGauge<Integer>() {
                   @Override
                   public Integer value() {
                       return queue.size();
                   }
               });
               queue.add("ssss");
               System.out.println(g.value());
               while(true){
                       Thread.sleep(1000);
               }
        }
}

运行效果例如以下：

12-12-20 14:48:53==============================================================
com.alibaba.cxf.test.metric.TestGauges:
  pending-jobs:
    value = 1

代码中都添加�了ConsoleReporter.enable(1, TimeUnit.SECONDS);语句，通过这个命令，能够每秒钟将度量指标打印在屏幕上，理解起来会有更清楚的理解。

Counter，计数器

package com.alibaba.cxf.test.metric;

import java.util.LinkedList;
import java.util.Queue;
import java.util.concurrent.TimeUnit;

import com.yammer.metrics.Metrics;
import com.yammer.metrics.core.Counter;
import com.yammer.metrics.reporting.ConsoleReporter;

/**
 * TODO
 * @author scutshuxue.chenxf
 */
public class TestCounter {

        private final Counter pendingJobs = Metrics.newCounter(TestCounter.class, "pending-jobs");
        private final Queue<String> queue = new LinkedList<String>();

        public void add(Stringstr) {
            pendingJobs.inc();
            queue.offer(str);
        }

        public String take() {
            pendingJobs.dec();
            return queue.poll();
        }
        /**
         * TODO
         * @author scutshuxue.chenxf
         * @param args
         * void
         * @throws InterruptedException
         */
        public static void main(String[]args) throws InterruptedException {
               // TODOAuto-generated method stub
               TestCounter tc =new TestCounter();
               ConsoleReporter.enable(1,TimeUnit.SECONDS);
               while(true){
                       tc.add("1");
                       Thread.sleep(1000);
               }
        }

}

效果例如以下：

12-12-20 14:48:53==============================================================
com.alibaba.cxf.test.metric.TestGauges:
  pending-jobs:
    value = 1

Meters

Meters会将近期1分钟，5分钟，15分钟的TPS（每秒处理的request数）给打印出来，还有全部时间的TPS。

package com.alibaba.cxf.test.metric;

import java.util.concurrent.TimeUnit;

import com.yammer.metrics.Metrics;
import com.yammer.metrics.core.Meter;
import com.yammer.metrics.reporting.ConsoleReporter;

/**
 * TODO
 * @author scutshuxue.chenxf
 */
public class TestMeters {
        private static Meter meter = Metrics.newMeter(TestMeters.class, "requests","requests", TimeUnit.SECONDS);

        public static void main(String[] args) throws InterruptedException{
               ConsoleReporter.enable(1,TimeUnit.SECONDS);
               while(true){
                       meter.mark();
                       meter.mark();
                       Thread.sleep(1000);
               }
        }
}

效果例如以下：

12-12-20 15:02:50==============================================================
com.alibaba.cxf.test.metric.TestMeters:
  requests:
             count = 20
         mean rate = 2.20requests/s
     1-minute rate = 2.00requests/s
     5-minute rate = 2.00requests/s
15-minute rate = 2.00requests/s

Histograms 直方图

最大值，最小值，平均值，方差，中位值，百分比数据，如75%,90%,98%,99%的数据在哪个范围内。

package com.alibaba.cxf.test.metric;

import java.util.concurrent.TimeUnit;

import com.yammer.metrics.Metrics;
import com.yammer.metrics.core.Histogram;
import com.yammer.metrics.reporting.ConsoleReporter;

/**
 * TODO
 * @author scutshuxue.chenxf
 */
public class TestHistograms {
        private static Histogram histo = Metrics.newHistogram(TestHistograms.class,"histo-sizes");

        /**
         * TODO
         * @author scutshuxue.chenxf
         * @param args
         * void
         * @throws InterruptedException
         */
        public static void main(String[] args) throws InterruptedException {
               // TODOAuto-generated method stub

               ConsoleReporter.enable(1,TimeUnit.SECONDS);
               int i=0;
               while(true){
                       histo.update(i++);
                       Thread.sleep(1000);
               }
        }

}

效果例如以下：

com.alibaba.cxf.test.metric.TestHistograms:
  histo-sizes:
               min = 0.00
               max = 5.00
              mean = 2.50
            stddev = 1.87
            median = 2.50
              75% <= 4.25
              95% <= 5.00
              98% <= 5.00
              99% <= 5.00
            99.9% <= 5.00

Timers

时间统计

package com.alibaba.cxf.test.metric;

import java.util.Random;
import java.util.concurrent.TimeUnit;

import com.yammer.metrics.Metrics;
import com.yammer.metrics.core.Timer;
import com.yammer.metrics.core.TimerContext;
import com.yammer.metrics.reporting.ConsoleReporter;

/**
 * TODO
 * @author scutshuxue.chenxf
 */
public class TestTimers {
        private static Timer timer = Metrics.newTimer(TestTimers.class, "responses", TimeUnit.MILLISECONDS,TimeUnit.SECONDS);
        /**
         * TODO
         * @author scutshuxue.chenxf
         * @param args
         * void
         * @throws InterruptedException
         */
        public static voidmain(String[] args) throws InterruptedException {
               // TODOAuto-generated method stub
               ConsoleReporter.enable(2,TimeUnit.SECONDS);
               Random rn = newRandom();
               timer.time();
               System.out.println();
               while(true){
                       TimerContextcontext = timer.time();

                       Thread.sleep(rn.nextInt(1000));
                       context.stop();
               }
        }

}

效果例如以下:

com.alibaba.cxf.test.metric.TestTimers:
  responses:
             count = 26
         mean rate = 2.15calls/s
     1-minute rate = 1.70calls/s
     5-minute rate = 1.62calls/s
    15-minute rate = 1.61calls/s
               min = 35.47ms
               max = 878.76ms
              mean = 462.50ms
            stddev = 284.91ms
            median = 419.90ms
              75% <=764.13ms
              95% <=877.76ms
              98% <=878.76ms
              99% <=878.76ms
            99.9% <=878.76ms

Health Checks

健康检查，如心跳：

package com.alibaba.cxf.test.metric;

import java.util.Map;
import java.util.Map.Entry;
import java.util.Random;
import java.util.concurrent.TimeUnit;

import com.yammer.metrics.HealthChecks;
import com.yammer.metrics.core.HealthCheck;
import com.yammer.metrics.reporting.ConsoleReporter;

public class DatabaseHealthCheck extends HealthCheck {
    private static Databasedatabase;
        private static final Map<String, Result> results = HealthChecks.runHealthChecks();

    public DatabaseHealthCheck(Databasedatabase) {
       super("database");
        this.database =database;
    }

    @Override
    public Result check()throws Exception {

        if(database.isConnected()) {
            returnResult.healthy();
        } else {
            return Result.unhealthy("Cannotconnect to database" );
        }
    }

    public static void main(String[] args) throws Exception{
        Database db = new Database();
        DatabaseHealthCheck checkHealth = new DatabaseHealthCheck(db);
               HealthChecks.register(checkHealth);

               while(true){
                       Map<String,Result> results = HealthChecks.runHealthChecks();
                       for(Entry<String, Result> entry : results.entrySet()) {
                           if (entry.getValue().isHealthy()) {
                               System.out.println(entry.getKey() +" is healthy");
                           } else {
                               System.err.println(entry.getKey() +" is UNHEALTHY: " + entry.getValue().getMessage());
                           }
                       }
                       Thread.sleep(1000);
               }
    }
}
class Database{
        static Random rn = newRandom();

        public booleanisConnected() {
               // TODOAuto-generated method stub
               returnrn.nextBoolean();
        }

}

效果例如以下：

com.alibaba.cxf.test.metric.TestTimers:
  responses:
             count = 26
         mean rate = 2.15calls/s
     1-minute rate = 1.70calls/s
     5-minute rate = 1.62calls/s
    15-minute rate = 1.61calls/s
               min = 35.47ms
               max = 878.76ms
              mean = 462.50ms
            stddev = 284.91ms
            median = 419.90ms
              75% <=764.13ms
              95% <=877.76ms
              98% <=878.76ms
              99% <=878.76ms
            99.9% <=878.76ms