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 class com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck extends com.codahale.metrics.health.HealthCheck
  minor version: 0
  major version: 59
  flags: flags: (0x0021) ACC_PUBLIC, ACC_SUPER
  this_class: com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck
  super_class: com.codahale.metrics.health.HealthCheck
{
  private final com.codahale.metrics.jvm.ThreadDeadlockDetector detector;
    descriptor: Lcom/codahale/metrics/jvm/ThreadDeadlockDetector;
    flags: (0x0012) ACC_PRIVATE, ACC_FINAL

  public void <init>();
    descriptor: ()V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=3, locals=1, args_size=1
        start local 0 // com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck this
         0: .line 18
            aload 0 /* this */
            new com.codahale.metrics.jvm.ThreadDeadlockDetector
            dup
            invokespecial com.codahale.metrics.jvm.ThreadDeadlockDetector.<init>:()V
            invokespecial com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck.<init>:(Lcom/codahale/metrics/jvm/ThreadDeadlockDetector;)V
         1: .line 19
            return
        end local 0 // com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck this
      LocalVariableTable:
        Start  End  Slot  Name  Signature
            0    2     0  this  Lcom/codahale/metrics/health/jvm/ThreadDeadlockHealthCheck;

  public void <init>(com.codahale.metrics.jvm.ThreadDeadlockDetector);
    descriptor: (Lcom/codahale/metrics/jvm/ThreadDeadlockDetector;)V
    flags: (0x0001) ACC_PUBLIC
    Code:
      stack=2, locals=2, args_size=2
        start local 0 // com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck this
        start local 1 // com.codahale.metrics.jvm.ThreadDeadlockDetector detector
         0: .line 26
            aload 0 /* this */
            invokespecial com.codahale.metrics.health.HealthCheck.<init>:()V
         1: .line 27
            aload 0 /* this */
            aload 1 /* detector */
            putfield com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck.detector:Lcom/codahale/metrics/jvm/ThreadDeadlockDetector;
         2: .line 28
            return
        end local 1 // com.codahale.metrics.jvm.ThreadDeadlockDetector detector
        end local 0 // com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck this
      LocalVariableTable:
        Start  End  Slot      Name  Signature
            0    3     0      this  Lcom/codahale/metrics/health/jvm/ThreadDeadlockHealthCheck;
            0    3     1  detector  Lcom/codahale/metrics/jvm/ThreadDeadlockDetector;
    MethodParameters:
          Name  Flags
      detector  

  protected com.codahale.metrics.health.HealthCheck$Result check();
    descriptor: ()Lcom/codahale/metrics/health/HealthCheck$Result;
    flags: (0x0004) ACC_PROTECTED
    Code:
      stack=1, locals=2, args_size=1
        start local 0 // com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck this
         0: .line 32
            aload 0 /* this */
            getfield com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck.detector:Lcom/codahale/metrics/jvm/ThreadDeadlockDetector;
            invokevirtual com.codahale.metrics.jvm.ThreadDeadlockDetector.getDeadlockedThreads:()Ljava/util/Set;
            astore 1 /* threads */
        start local 1 // java.util.Set threads
         1: .line 33
            aload 1 /* threads */
            invokeinterface java.util.Set.isEmpty:()Z
            ifeq 3
         2: .line 34
            invokestatic com.codahale.metrics.health.HealthCheck$Result.healthy:()Lcom/codahale/metrics/health/HealthCheck$Result;
            areturn
         3: .line 36
      StackMap locals: java.util.Set
      StackMap stack:
            aload 1 /* threads */
            invokevirtual java.lang.Object.toString:()Ljava/lang/String;
            invokestatic com.codahale.metrics.health.HealthCheck$Result.unhealthy:(Ljava/lang/String;)Lcom/codahale/metrics/health/HealthCheck$Result;
            areturn
        end local 1 // java.util.Set threads
        end local 0 // com.codahale.metrics.health.jvm.ThreadDeadlockHealthCheck this
      LocalVariableTable:
        Start  End  Slot     Name  Signature
            0    4     0     this  Lcom/codahale/metrics/health/jvm/ThreadDeadlockHealthCheck;
            1    4     1  threads  Ljava/util/Set<Ljava/lang/String;>;
    Exceptions:
      throws java.lang.Exception
}
SourceFile: "ThreadDeadlockHealthCheck.java"
InnerClasses:
  public Result = com.codahale.metrics.health.HealthCheck$Result of com.codahale.metrics.health.HealthCheck