Metrics 3.1.0 released!

[Ryan Tenney]

Metrics 3.1.0 has been released at long last!

For this and all subsequent releases the group id has changed to 'io.dropwizard.metrics'.  However, for backwards compatibility with the 3.0 release, the java package is still 'com.codahale.metrics'.  Yes, this is perhaps slightly confusing, but the alternative was to break backwards compatibility and all third party modules.

Known issues:

• Binary incompatibility with GraphiteReporter.Builder#build, which will prevent any code compiled against 3.0 from successfully creating a graphite reporter
  
• Log4j2 InstrumentedAppender is in the wrong package. This will be fixed in 3.1.1, despite it being a breaking change.

For any other issues, please check for a duplicate issue at https://github.com/dropwizard/metrics/milestones/3.1.1 and then open an issue at https://github.com/dropwizard/metrics/issues/new

There will be a bugfix release within 2 weeks to address any issues introduced in this release.

Given the number of changes which occurred in this release it took a little while to assemble a changelog, thus the delay in this announcement.  Please see the (hopefully comprehensive) changelog below.

Cheers,

Ryan

Changelog

New Modules

• Upgrade to Jetty 9.1 (metrics-jetty9, Jetty 9.0 module renamed to metrics-jetty9-legacy)
• Add log4j2 support (metrics-log4j2)
• Upgrade to Jersey2 (metrics-jersey2)
• Add httpasyncclient support (metrics-httpasyncclient)

General

• Changed maven groupId to io.dropwizard.metrics
• Enable Java8 builds on Travis, fix javadocs and disable some doclinting
• Fixing some compilation warnings about missing generics and varargs invocation

Core

• Instrumentation for java.util.concurrent classes
• ExponentiallyDecayingReservoir: quantiles weighting
• Loosen type requirements for JmxAttributeGauge constructor
• SlidingWindowReservoir - ArrayOutOfBoundsException thrown if # of Reservoir examples exceeds Integer max value
• Classloader metrics
• Add an instrumented ScheduledExecutorService
• Fix race condition in InstrumentedThreadFactoryTest
• Correct comparison of System.nanoTime in SlidingTimeWindowReservoir

Health Checks

• Add SharedHealthCheckRegistries class

Benchmarks

• Migrate benchmarks from Caliper to JMH

Annotations

• New annotations: @CachedGauge, @Counted, @Metric
• Support for annotations on classes and constructors
• Allow @Metric on methods and parameters
• Add @Inherited and @Documented on all type annotations

Ehcache

• Adapted ehcache integration to latest ehcache version 2.8.3

HttpClient

• Upgrade to HttpClient 4.3

Jetty

• InstrumentedHandler: Remove duplicate calls to requests.update(...)
• New metric 'utilization-max' to track thread usage out of max pool size in jetty
• Replaced Jetty-specific Request with Servlet API interfaces
• Jetty 8: Avoid NPE if InstrumentedQueuedThreadPool gauges are read too early
• Jetty 8: Call updateResponses onComplete of ContinuationListener
• Allow specifying a custom prefix Jetty 9 InstrumentedHandler

JSON

• MetricsModule is serializing wrong minute rates for timers
• MeterSerializer.serialize had m1_rate and m15_rate transposed

JVM

• Add CachedThreadStatesGaugeSet
• Monitor count of deadlock threads
• Prevent exceptions from ThreadDumpServlet on Google AppEngine

Logback

• Upgrade to logback 1.1.1
• Allow InstrumentedAppender use in logback.xml

Servlet

• Use getClass() in place of AbstractInstrumentedFilter.class in generated metric names
• Update MetricsServlet with support for JSONP as alternative to CORS
• Specify the base name of the metrics as a filter init-param for the metrics captured in the AbstractInstrumentedFilter

Servlets

• Add option to provide MetricFilter to MetricsServlet
• AdminServlet generates link to pretty printed healthchecks
• MetricsServlet.ContextListener doesn't initialize the context correctly

Reporters

• Every reporter implements Reporter interface to indicate that is a Reporter

Scheduled Reporter

• Added support for passing a ScheduledExecutorService to ScheduledReporters
• Improve the ScheduledReporter#stop method
• Ensure ScheduledReporters get unique thread pools.
• Suppress runtime exceptions thrown from ScheduledReporter#report

Jmx Reporter

• Ability to inject a factory of ObjectName
• Lazy fetch of PlatformMBeanServer
• JMX Reporter throws exception when metric name contains an asterisk
• onTimerRemoved in JmxListener calls registered.add
• Support for mBean servers that rewrite the supplied ObjectName upon registration

Graphite

• Graphite reporter does not notify when Graphite/Carbon server is unreachable
• Persistent connections to Graphite
• Graphite constructor accepts host/port
• Graphtie Pickle sender
• Graphite UDP sender
• Graphite AMQP sender

Ganglia Reporter

• Add a threshold/minimum value to report before converting results to 0
• Report to multiple gmetric instances
• Escape slahes on ganglia metric names

Slf4j Reporter

• Upgrade slf4j to 1.7.6
• Enhancement for logging level option on Slf4jReporter