http://metrics.dropwizard.io/metrics-core: Metrics is a Java library which gives you unparalleled insight into what your code does in production. Metrics provides a powerful toolkit of ways to measure the behavior of critical components in your production environment.
  • Coda Hale
  • Ryan Tenney
  • Artem Prigoda 
public abstract class com.codahale.metrics.DerivativeGauge<F, T> implements com.codahale.metrics.Gauge<T>
  minor version: 0
  major version: 59
  flags: flags: (0x0421) ACC_PUBLIC, ACC_SUPER, ACC_ABSTRACT
  this_class: com.codahale.metrics.DerivativeGauge
  super_class: java.lang.Object
{
  private final com.codahale.metrics.Gauge<F> base;
    descriptor: Lcom/codahale/metrics/Gauge;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL
    Signature: Lcom/codahale/metrics/Gauge<TF;>;

  protected void <init>(com.codahale.metrics.Gauge<F>);
    descriptor: (Lcom/codahale/metrics/Gauge;)V
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.codahale.metrics.DerivativeGauge this
        start local 1 // com.codahale.metrics.Gauge base
         0: .line 17
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
         1: .line 18
            aload 0 /* this */
            aload 1 /* base */
            putfield com.codahale.metrics.DerivativeGauge.base:Lcom/codahale/metrics/Gauge;
         2: .line 19
            return
        end local 1 // com.codahale.metrics.Gauge base
        end local 0 // com.codahale.metrics.DerivativeGauge this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    3     0  this  Lcom/codahale/metrics/DerivativeGauge<TF;TT;>;
            0    3     1  base  Lcom/codahale/metrics/Gauge<TF;>;
    Signature: (Lcom/codahale/metrics/Gauge<TF;>;)V
    MethodParameters:
      Name  Flags
      base  

  public T getValue();
    descriptor: ()Ljava/lang/Object;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=1, args_size=1
        start local 0 // com.codahale.metrics.DerivativeGauge this
         0: .line 23
            aload 0 /* this */
            aload 0 /* this */
            getfield com.codahale.metrics.DerivativeGauge.base:Lcom/codahale/metrics/Gauge;
            invokeinterface com.codahale.metrics.Gauge.getValue:()Ljava/lang/Object;
            invokevirtual com.codahale.metrics.DerivativeGauge.transform:(Ljava/lang/Object;)Ljava/lang/Object;
            areturn
        end local 0 // com.codahale.metrics.DerivativeGauge this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/codahale/metrics/DerivativeGauge<TF;TT;>;
    Signature: ()TT;

  protected abstract T transform();
    descriptor: (Ljava/lang/Object;)Ljava/lang/Object;
    flags: (0x0404) ACC_PROTECTED, ACC_ABSTRACT
    Signature: (TF;)TT;
    MethodParameters:
       Name  Flags
      value  
}
Signature: <F:Ljava/lang/Object;T:Ljava/lang/Object;>Ljava/lang/Object;Lcom/codahale/metrics/Gauge<TT;>;
SourceFile: "DerivativeGauge.java"