title: What metrics-core does Dropwizard uses by default?
body: <p>I've been trying to figure out MetricRegistry details for one of my project based out on <a href="http://www.dropwizard.io/1.1.0/docs/about/index.html" rel="nofollow noreferrer"><code>dropwizard:1.1.0</code></a></p>
  
  <p><a href="https://i.stack.imgur.com/KefX9.png" rel="nofollow noreferrer"><img src="https://i.stack.imgur.com/KefX9.png" alt="enter image description here"></a></p>
  
  <p>A minor confusion here is that I see the version used for <code>localhost:8181/metrics</code> (adminConnector) by my service is <strong>3.1.3</strong> which is not the latest and the one included in <code>dropwizard-core</code> (<strong>Note</strong> : +- io.dropwizard.metrics:metrics-core:jar:3.2.2 in the dependency:tree below)</p>
  
  <p>Relative POM dependencies used are :</p>
  
  <pre><code>&lt;dependency&gt;
      &lt;groupId&gt;io.dropwizard&lt;/groupId&gt;
      &lt;artifactId&gt;dropwizard-core&lt;/artifactId&gt;
      &lt;version&gt;1.1.0&lt;/version&gt;
  &lt;/dependency&gt;
  &lt;dependency&gt;
      &lt;groupId&gt;io.federecio&lt;/groupId&gt;
      &lt;artifactId&gt;dropwizard-swagger&lt;/artifactId&gt;
      &lt;version&gt;0.7.0&lt;/version&gt;
  &lt;/dependency&gt;
  </code></pre>
  
  <p><strong><code>mvn dependency:tree</code></strong> for the projects is as follows : </p>
  
  <pre><code> +- io.dropwizard:dropwizard-core:jar:1.1.0:compile
  [INFO] |  +- io.dropwizard:dropwizard-util:jar:1.1.0:compile
  [INFO] |  |  +- com.fasterxml.jackson.core:jackson-annotations:jar:2.8.0:compile
  [INFO] |  |  +- com.google.code.findbugs:jsr305:jar:3.0.1:compile
  [INFO] |  |  \- joda-time:joda-time:jar:2.9.7:compile
  [INFO] |  +- io.dropwizard:dropwizard-jackson:jar:1.1.0:compile
  [INFO] |  |  +- com.fasterxml.jackson.core:jackson-core:jar:2.8.7:compile
  [INFO] |  |  +- com.fasterxml.jackson.core:jackson-databind:jar:2.8.7:compile
  [INFO] |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-guava:jar:2.8.7:compile
  [INFO] |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-jsr310:jar:2.8.7:compile
  [INFO] |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-jdk8:jar:2.8.7:compile
  [INFO] |  |  +- com.fasterxml.jackson.module:jackson-module-parameter-names:jar:2.8.7:compile
  [INFO] |  |  +- com.fasterxml.jackson.module:jackson-module-afterburner:jar:2.8.7:compile
  [INFO] |  |  +- com.fasterxml.jackson.datatype:jackson-datatype-joda:jar:2.8.7:compile
  [INFO] |  |  +- org.slf4j:slf4j-api:jar:1.7.24:compile
  [INFO] |  |  \- ch.qos.logback:logback-classic:jar:1.2.1:compile
  [INFO] |  +- io.dropwizard:dropwizard-validation:jar:1.1.0:compile
  [INFO] |  |  +- org.hibernate:hibernate-validator:jar:5.3.4.Final:compile
  [INFO] |  |  |  +- org.jboss.logging:jboss-logging:jar:3.3.0.Final:compile
  [INFO] |  |  |  \- com.fasterxml:classmate:jar:1.3.1:compile
  [INFO] |  |  \- org.glassfish:javax.el:jar:3.0.0:compile
  [INFO] |  +- io.dropwizard:dropwizard-configuration:jar:1.1.0:compile
  [INFO] |  |  \- com.fasterxml.jackson.dataformat:jackson-dataformat-yaml:jar:2.8.7:compile
  [INFO] |  |     \- org.yaml:snakeyaml:jar:1.17:compile
  [INFO] |  +- io.dropwizard:dropwizard-logging:jar:1.1.0:compile
  [INFO] |  |  +- io.dropwizard.metrics:metrics-logback:jar:3.2.2:compile
  [INFO] |  |  +- org.slf4j:jul-to-slf4j:jar:1.7.24:compile
  [INFO] |  |  +- ch.qos.logback:logback-core:jar:1.2.1:compile
  [INFO] |  |  +- org.slf4j:log4j-over-slf4j:jar:1.7.24:compile
  [INFO] |  |  +- org.slf4j:jcl-over-slf4j:jar:1.7.24:compile
  [INFO] |  |  \- org.eclipse.jetty:jetty-util:jar:9.4.2.v20170220:compile
  [INFO] |  +- io.dropwizard:dropwizard-metrics:jar:1.1.0:compile
  [INFO] |  +- io.dropwizard:dropwizard-jersey:jar:1.1.0:compile
  [INFO] |  |  +- org.glassfish.jersey.core:jersey-server:jar:2.25.1:compile
  [INFO] |  |  |  +- org.glassfish.jersey.core:jersey-common:jar:2.25.1:compile
  [INFO] |  |  |  |  +- org.glassfish.jersey.bundles.repackaged:jersey-guava:jar:2.25.1:compile
  [INFO] |  |  |  |  \- org.glassfish.hk2:osgi-resource-locator:jar:1.0.1:compile
  [INFO] |  |  |  +- org.glassfish.jersey.core:jersey-client:jar:2.25.1:compile
  [INFO] |  |  |  +- org.glassfish.jersey.media:jersey-media-jaxb:jar:2.25.1:compile
  [INFO] |  |  |  +- javax.annotation:javax.annotation-api:jar:1.2:compile
  [INFO] |  |  |  +- org.glassfish.hk2:hk2-api:jar:2.5.0-b32:compile
  [INFO] |  |  |  |  +- org.glassfish.hk2:hk2-utils:jar:2.5.0-b32:compile
  [INFO] |  |  |  |  \- org.glassfish.hk2.external:aopalliance-repackaged:jar:2.5.0-b32:compile
  [INFO] |  |  |  +- org.glassfish.hk2.external:javax.inject:jar:2.5.0-b32:compile
  [INFO] |  |  |  \- org.glassfish.hk2:hk2-locator:jar:2.5.0-b32:compile
  [INFO] |  |  |     \- org.javassist:javassist:jar:3.20.0-GA:compile
  [INFO] |  |  +- org.glassfish.jersey.ext:jersey-metainf-services:jar:2.25.1:compile
  [INFO] |  |  +- org.glassfish.jersey.ext:jersey-bean-validation:jar:2.25.1:compile
  [INFO] |  |  |  +- javax.el:javax.el-api:jar:2.2.4:compile
  [INFO] |  |  |  \- org.glassfish.web:javax.el:jar:2.2.4:compile
  [INFO] |  |  +- io.dropwizard.metrics:metrics-jersey2:jar:3.2.2:compile
  [INFO] |  |  +- com.fasterxml.jackson.jaxrs:jackson-jaxrs-json-provider:jar:2.8.7:compile
  [INFO] |  |  |  +- com.fasterxml.jackson.jaxrs:jackson-jaxrs-base:jar:2.8.7:compile
  [INFO] |  |  |  \- com.fasterxml.jackson.module:jackson-module-jaxb-annotations:jar:2.8.7:compile
  [INFO] |  |  +- org.glassfish.jersey.containers:jersey-container-servlet:jar:2.25.1:compile
  [INFO] |  |  |  \- org.glassfish.jersey.containers:jersey-container-servlet-core:jar:2.25.1:compile
  [INFO] |  |  +- org.eclipse.jetty:jetty-server:jar:9.4.2.v20170220:compile
  [INFO] |  |  |  +- javax.servlet:javax.servlet-api:jar:3.1.0:compile
  [INFO] |  |  |  \- org.eclipse.jetty:jetty-io:jar:9.4.2.v20170220:compile
  [INFO] |  |  +- org.eclipse.jetty:jetty-webapp:jar:9.4.2.v20170220:compile
  [INFO] |  |  |  \- org.eclipse.jetty:jetty-xml:jar:9.4.2.v20170220:compile
  [INFO] |  |  \- org.eclipse.jetty:jetty-continuation:jar:9.4.2.v20170220:compile
  [INFO] |  +- io.dropwizard:dropwizard-servlets:jar:1.1.0:compile
  [INFO] |  |  \- io.dropwizard.metrics:metrics-annotation:jar:3.2.2:compile
  [INFO] |  +- io.dropwizard:dropwizard-jetty:jar:1.1.0:compile
  [INFO] |  |  +- io.dropwizard.metrics:metrics-jetty9:jar:3.2.2:compile
  [INFO] |  |  +- org.eclipse.jetty:jetty-servlet:jar:9.4.2.v20170220:compile
  [INFO] |  |  |  \- org.eclipse.jetty:jetty-security:jar:9.4.2.v20170220:compile
  [INFO] |  |  +- org.eclipse.jetty:jetty-servlets:jar:9.4.2.v20170220:compile
  [INFO] |  |  \- org.eclipse.jetty:jetty-http:jar:9.4.2.v20170220:compile
  [INFO] |  +- io.dropwizard:dropwizard-lifecycle:jar:1.1.0:compile
  [INFO] |  +- io.dropwizard.metrics:metrics-core:jar:3.2.2:compile
  [INFO] |  +- io.dropwizard.metrics:metrics-jvm:jar:3.2.2:compile
  [INFO] |  +- io.dropwizard.metrics:metrics-servlets:jar:3.2.2:compile
  [INFO] |  |  +- io.dropwizard.metrics:metrics-json:jar:3.2.2:compile
  [INFO] |  |  \- com.papertrail:profiler:jar:1.0.2:compile
  [INFO] |  +- io.dropwizard.metrics:metrics-healthchecks:jar:3.2.2:compile
  [INFO] |  +- io.dropwizard:dropwizard-request-logging:jar:1.1.0:compile
  [INFO] |  |  \- ch.qos.logback:logback-access:jar:1.2.1:compile
  [INFO] |  +- net.sourceforge.argparse4j:argparse4j:jar:0.7.0:compile
  [INFO] |  \- org.eclipse.jetty.toolchain.setuid:jetty-setuid-java:jar:1.0.3:compile
  [INFO] +- io.federecio:dropwizard-swagger:jar:0.7.0:compile
  [INFO] |  +- io.dropwizard:dropwizard-assets:jar:0.8.0:compile
  [INFO] |  +- io.dropwizard:dropwizard-views:jar:0.8.0:compile
  [INFO] |  +- io.dropwizard:dropwizard-views-freemarker:jar:0.8.0:compile
  [INFO] |  |  \- org.freemarker:freemarker:jar:2.3.21:compile
  [INFO] |  +- com.wordnik:swagger-jersey2-jaxrs:jar:1.5.1-M2:compile
  [INFO] |  |  \- com.wordnik:swagger-jaxrs:jar:1.5.1-M2:compile
  [INFO] |  |     +- com.fasterxml.jackson.dataformat:jackson-dataformat-xml:jar:2.4.2:compile
  [INFO] |  |     |  \- org.codehaus.woodstox:stax2-api:jar:3.1.4:compile
  [INFO] |  |     +- com.wordnik:swagger-core:jar:1.5.1-M2:compile
  [INFO] |  |     |  \- com.wordnik:swagger-models:jar:1.5.1-M2:compile
  [INFO] |  |     |     \- com.wordnik:swagger-annotations:jar:1.5.1-M2:compile
  [INFO] |  |     \- org.reflections:reflections:jar:0.9.9:compile
  [INFO] |  |        \- com.google.code.findbugs:annotations:jar:2.0.1:compile
  [INFO] |  \- xml-apis:xml-apis:jar:1.4.01:compile
  [INFO] +- com.google.inject:guice:jar:4.1.0:compile
  [INFO] |  +- javax.inject:javax.inject:jar:1:compile
  [INFO] |  +- aopalliance:aopalliance:jar:1.0:compile
  [INFO] |  \- com.google.guava:guava:jar:19.0:compile
  [INFO] +- org.apache.httpcomponents:httpclient:jar:4.5.3:compile
  [INFO] |  +- org.apache.httpcomponents:httpcore:jar:4.4.6:compile
  [INFO] |  +- commons-logging:commons-logging:jar:1.2:compile
  [INFO] |  \- commons-codec:commons-codec:jar:1.9:compile
  [INFO] +- javax.ws.rs:javax.ws.rs-api:jar:2.0.1:compile
  [INFO] \- org.junit.jupiter:junit-jupiter-api:jar:5.0.0-M4:test
  [INFO]    +- org.opentest4j:opentest4j:jar:1.0.0-M2:test
  [INFO]    \- org.junit.platform:junit-platform-commons:jar:1.0.0-M4:test
  </code></pre>
  
  <p>Just wanted to know, how does Dropwizard configure the MetricRegistry?</p>
  
  <hr>
  
  <p><strong>Futher Details</strong> (if required) :- </p>
  
  <p>I am using guice injection to bind the <code>MetricRegistry</code> in a module extending <code>AbstractModule</code> as </p>
  
  <pre><code>bind(MetricRegistry.class).toInstance(environment.metrics());
  </code></pre>
  
  <p>and in a service class calling this injector as </p>
  
  <pre><code>public static void main(String[] args) throws Exception {
      new Service().run(args);
  }
  
  @Override
  public void run(ServiceConfig config, Environment environment) throws Exception {
      Injector injector = Guice.createInjector(new ExtendingModule(config, environment));
      .... // not altering metrics here
  }
  </code></pre>