http://metrics.dropwizard.io/metrics-healthchecks: An addition to Metrics which provides the ability to run application-specific health checks, allowing you to check your application's heath in production.
  • Coda Hale
  • Ryan Tenney
  • Artem Prigoda 
public abstract class com.codahale.metrics.health.HealthCheck
  minor version: 0
  major version: 59
  flags: flags: (0x0421) ACC_PUBLIC, ACC_SUPER, ACC_ABSTRACT
  this_class: com.codahale.metrics.health.HealthCheck
  super_class: java.lang.Object
{
  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.codahale.metrics.health.HealthCheck this
         0: .line 17
            aload 0 /* this */
            invokespecial java.lang.Object.<init>:()V
            return
        end local 0 // com.codahale.metrics.health.HealthCheck this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/codahale/metrics/health/HealthCheck;

  protected abstract com.codahale.metrics.health.HealthCheck$Result check();
    descriptor: ()Lcom/codahale/metrics/health/HealthCheck$Result;
    flags: (0x0404) ACC_PROTECTED, ACC_ABSTRACT
    Exceptions:
      throws java.lang.Exception

  public com.codahale.metrics.health.HealthCheck$Result execute();
    descriptor: ()Lcom/codahale/metrics/health/HealthCheck$Result;
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=6, locals=5, args_size=1
        start local 0 // com.codahale.metrics.health.HealthCheck this
         0: .line 371
            aload 0 /* this */
            invokevirtual com.codahale.metrics.health.HealthCheck.clock:()Lcom/codahale/metrics/Clock;
            invokevirtual com.codahale.metrics.Clock.getTick:()J
            lstore 1 /* start */
        start local 1 // long start
         1: .line 374
            aload 0 /* this */
            invokevirtual com.codahale.metrics.health.HealthCheck.check:()Lcom/codahale/metrics/health/HealthCheck$Result;
            astore 3 /* result */
        start local 3 // com.codahale.metrics.health.HealthCheck$Result result
         2: .line 375
            goto 5
        end local 3 // com.codahale.metrics.health.HealthCheck$Result result
      StackMap locals: com.codahale.metrics.health.HealthCheck long
      StackMap stack: java.lang.Exception
         3: astore 4 /* e */
        start local 4 // java.lang.Exception e
         4: .line 376
            aload 4 /* e */
            invokestatic com.codahale.metrics.health.HealthCheck$Result.unhealthy:(Ljava/lang/Throwable;)Lcom/codahale/metrics/health/HealthCheck$Result;
            astore 3 /* result */
        end local 4 // java.lang.Exception e
        start local 3 // com.codahale.metrics.health.HealthCheck$Result result
         5: .line 378
      StackMap locals: com.codahale.metrics.health.HealthCheck$Result
      StackMap stack:
            aload 3 /* result */
            getstatic java.util.concurrent.TimeUnit.MILLISECONDS:Ljava/util/concurrent/TimeUnit;
            aload 0 /* this */
            invokevirtual com.codahale.metrics.health.HealthCheck.clock:()Lcom/codahale/metrics/Clock;
            invokevirtual com.codahale.metrics.Clock.getTick:()J
            lload 1 /* start */
            lsub
            getstatic java.util.concurrent.TimeUnit.NANOSECONDS:Ljava/util/concurrent/TimeUnit;
            invokevirtual java.util.concurrent.TimeUnit.convert:(JLjava/util/concurrent/TimeUnit;)J
            invokevirtual com.codahale.metrics.health.HealthCheck$Result.setDuration:(J)V
         6: .line 379
            aload 3 /* result */
            areturn
        end local 3 // com.codahale.metrics.health.HealthCheck$Result result
        end local 1 // long start
        end local 0 // com.codahale.metrics.health.HealthCheck this
      LocalVariableTable:
        Start  End  Slot    Name  Signature
            0    7     0    this  Lcom/codahale/metrics/health/HealthCheck;
            1    7     1   start  J
            2    3     3  result  Lcom/codahale/metrics/health/HealthCheck$Result;
            5    7     3  result  Lcom/codahale/metrics/health/HealthCheck$Result;
            4    5     4       e  Ljava/lang/Exception;
      Exception table:
        from    to  target  type
           1     2       3  Class java.lang.Exception

  protected com.codahale.metrics.Clock clock();
    descriptor: ()Lcom/codahale/metrics/Clock;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=1, locals=1, args_size=1
        start local 0 // com.codahale.metrics.health.HealthCheck this
         0: .line 383
            invokestatic com.codahale.metrics.Clock.defaultClock:()Lcom/codahale/metrics/Clock;
            areturn
        end local 0 // com.codahale.metrics.health.HealthCheck this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    1     0  this  Lcom/codahale/metrics/health/HealthCheck;
}
SourceFile: "HealthCheck.java"
NestMembers:
  com.codahale.metrics.health.HealthCheck$Result  com.codahale.metrics.health.HealthCheck$ResultBuilder
InnerClasses:
  public Result = com.codahale.metrics.health.HealthCheck$Result of com.codahale.metrics.health.HealthCheck
  public ResultBuilder = com.codahale.metrics.health.HealthCheck$ResultBuilder of com.codahale.metrics.health.HealthCheck