Question

我尝试使用dropWizard库获取JVM指标值（MemoryUsageGaugeSet，GarbageCollectionUsageGaugeSet）

 <dependency>
    <groupId>io.dropwizard.metrics</groupId>
    <artifactId>metrics-jvm</artifactId>
    <version>3.1.2</version>
 </dependency>

代码实施。

  public static void main(String[] args ){
  MemoryUsageGaugeSet memory = new MemoryUsageGaugeSet();
  Map<String, Metric> memoryMap = memory.getMetrics();
  system.out.println( memoryMap);}

我得到的结果是

{heap.committed=com.codahale.metrics.jvm.MemoryUsageGaugeSet$8@d16011,nonheap.used=com.codahale.metrics.jvm.MemoryUsageGaugeSet$11@cc09904,pools.Code-Cache.used = com。 codahale.metrics.jvm.MemoryUsageGaugeSet$17@748032cc，pools.Code-Cache.committed=com.codahale.metrics.jvm.MemoryUsageGaugeSet$18@2b6e0423,dup.used=com.codahale.metrics.jvm.MemoryUsageGaugeSet$6@203428b7,pool .PS-Old-Gen.init = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 19 @ 28b49d0c，total.committed = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 4 @5dd7cc84，pools.PS-Old-Gen.max = com .codahale.metrics.jvm.MemoryUsageGaugeSet $ 16 @ 6438401，total.init = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 1 @ 7b365ee，nonheap.max = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 12@be3d4e9，pool。 PS-Eden-Space.init=com.codahale.metrics.jvm.MemoryUsageGaugeSet$19@68339afd，pools.Compressed-Class-Space.used=com.codahale.metrics.jvm.MemoryUsageGaugeSet$17@724a6876,pools.Metaspace.usage = com.codahale.metrics.jvm.MemoryUsageGaugeSet$15@6ecaffc4， pools.Metaspace.max=com.codahale.metrics.jvm.MemoryUsageGaugeSet$16@7b1b3a68,poolrs.PS-Eden-Space.committed=com.codahale.metrics.jvm.MemoryUsageGaugeSet$18@f8ba384,poolrs.PS-Eden-Space。 max = com.codahale.metrics.jvm.MemoryUsageGaugeSet$16@2e2373db，pools.Compressed-Class-Space.usage=com.codahale.metrics.jvm.MemoryUsageGaugeSet$15@17ae8d04,dup.usage = com.codahale.metrics.jvm。 MemoryUsageGaugeSet $ 9 @ 35c43de3，pools.PS-Eden-Space.usage=com.codahale.metrics.jvm.MemoryUsageGaugeSet$15@67013f5c，pools.PS-Survivor-Space.max=com.codahale.metrics.jvm.MemoryUsageGaugeSet$16@520935cc ，pools.Code-Cache.max=com.codahale.metrics.jvm.MemoryUsageGaugeSet$16@31ac5424，pools.Compressed-Class-Space.init=com.codahale.metrics.jvm.MemoryUsageGaugeSet$19@25135cd7,pools.Metaspace.init =com.codahale.metrics.jvm.MemoryUsageGaugeSet$19@4b066cf6，pools.PS-Survivor-Space.usage=com.codahale.metrics.jvm.MemoryUsageGaugeSet$15@50ba970f，pools.PS-Old-Gen.usage = com.codahale .metrics.jvm.MemoryUsageGaugeSet $ 15 @ 3e4e448，pool s.Code-Cache.usage=com.codahale.metrics.jvm.MemoryUsageGaugeSet$15@3c2ef507,poolrs.PS-Survivor-Space.init=com.codahale.metrics.jvm.MemoryUsageGaugeSet$19@44374fa8,total.used = com。 codahale.metrics.jvm.MemoryUsageGaugeSet$2@40b1aace，pools.Code-Cache.init=com.codahale.metrics.jvm.MemoryUsageGaugeSet$19@6453d034，pools.PS-Old-Gen.committed = com.codahale.metrics.jvm。 MemoryUsageGaugeSet $ 18 @ 2f9e8774，heap.init = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 5 @ 512127，nonheap.committed = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 13@1c80e011，pools.Compressed-Class-Space.committed =com.codahale.metrics.jvm.MemoryUsageGaugeSet$18@662841c5,nonheap.init=com.codahale.metrics.jvm.MemoryUsageGaugeSet$10@3dd6cf53，pools.PS-Eden-Space.used = com.codahale.metrics.jvm .MemoryUsageGaugeSet $ 17 @ 3a428c1e，nonheap.usage = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 14 @ 21d9632f，heap.max = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 7 @5db28b8，pools.PS-Survivor-Space。二手= com.codahale.metrics.jvm.MemoryUsageGaug eSet $ 17 @ efcd307，pools.Metaspace.committed = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 18 @ 20f09cba，total.max = com.codahale.metrics.jvm.MemoryUsageGaugeSet $ 3 @ 4ada5390，pools.Metaspace.used = com.codahale .metrics.jvm.MemoryUsageGaugeSet $ 17 @ 16982c9b，pools.Compressed-Class-Space.max=com.codahale.metrics.jvm.MemoryUsageGaugeSet$16@7e94b1a4，pools.PS-Survivor-Space.committed = com.codahale.metrics.jvm .MemoryUsageGaugeSet $ 18 @ 5aa5f780，pools.PS-Old-Gen.used=com.codahale.metrics.jvm.MemoryUsageGaugeSet$17@427b7997}

我得到了对象的引用，而不是我想获取这些引用的值。该怎么做？

Answer 1

要获取/打印对象的值，您需要在课程中实施toString()而MemoryUsageGaugeSet没有。验证@ javadoc

一种方法是使用您自己的实现toString()扩展该类。

另一种方法是迭代地图并打印每个值。你可能想尝试下面的东西..

Map<String, Metric> memoryMap = memory.getMetrics();

for (String key : memoryMap.keySet()) {
    Metric m = memoryMap.get(key);
    System.out.println(m.getClass());

    if (m instanceof Gauge) {
        System.out.println(((Gauge<Long>) m).getValue());
    }
}

MemoryUsageGaugeSet会产生Gauge<Long> Metric的实现。

希望这有帮助。

使用DropWizard metrics-Jvm

1 个答案: