Added examples of Apache Commons Pool

docs/antora.yml

@@ -17,3 +17,4 @@ asciidoc:
     chomp: 'all'
     include-java: 'example$docs-src/test/java/io/micrometer/docs'
     include-resources: 'example$docs-src/test/resources'
+    include-core-test-java: 'example$core-test'

docs/modules/ROOT/examples/core-test

@@ -0,0 +1 @@
+../../../../micrometer-core/src/test/java

docs/modules/ROOT/nav.adoc

@@ -35,6 +35,7 @@
 ** xref:implementations/statsD.adoc[statsD]
 ** xref:implementations/wavefront.adoc[Wavefront]
 * xref:reference.adoc[Reference Instrumentations]
+** xref:reference/commons-pool.adoc[Apache Commons Pool]
 ** xref:reference/jvm.adoc[JVM]
 ** xref:reference/cache.adoc[Cache]
 ** xref:reference/okhttpclient.adoc[OkHttpClient]

docs/modules/ROOT/pages/reference/commons-pool.adoc

@@ -0,0 +1,18 @@
+[[overview]]
+= Apache Commons Pool Instrumentation
+
+https://commons.apache.org/proper/commons-pool/[Apache Commons Pool] is an open source software library provides an object-pooling API and a number of object pool implementations.
+
+Below you can find an example of how to instrument Apache Commons Pool with Micrometer.
+
+[source,java,subs=+attributes]
+-----
+// Setting up instrumentation
+include::{include-core-test-java}/io/micrometer/core/instrument/binder/commonspool2/CommonsObjectPool2MetricsTest.java[tags=setup, indent=0]
+
+// Generic Pool instrumentation (with examples of created meters)
+include::{include-core-test-java}/io/micrometer/core/instrument/binder/commonspool2/CommonsObjectPool2MetricsTest.java[tags=generic_pool, indent=0]
+
+// Generic Keyed Pool instrumentation (with examples of created meters)
+include::{include-core-test-java}/io/micrometer/core/instrument/binder/commonspool2/CommonsObjectPool2MetricsTest.java[tags=generic_keyed_pool, indent=0]
+-----

micrometer-core/src/test/java/io/micrometer/core/instrument/binder/commonspool2/CommonsObjectPool2MetricsTest.java

@@ -45,15 +45,19 @@ class CommonsObjectPool2MetricsTest {
 
     private final MeterRegistry registry = new SimpleMeterRegistry();
 
+    // tag::setup[]
     private final CommonsObjectPool2Metrics commonsObjectPool2Metrics = new CommonsObjectPool2Metrics(tags);
 
+    // end::setup[]
+
     @AfterEach
     void afterEach() {
         commonsObjectPool2Metrics.close();
     }
 
     @Test
     void verifyMetricsWithExpectedTags() {
+        // tag::generic_pool[]
         try (GenericObjectPool<Object> p = createGenericObjectPool()) {
             MeterRegistry registry = new SimpleMeterRegistry();
             commonsObjectPool2Metrics.bindTo(registry);
@@ -72,10 +76,12 @@ void verifyMetricsWithExpectedTags() {
                         "commons.pool2.mean.borrow.wait")
                 .forEach(name -> registry.get(name).tags(tags).timeGauge());
         }
+        // end::generic_pool[]
     }
 
     @Test
     void verifyGenericKeyedObjectPoolMetricsWithExpectedTags() {
+        // tag::generic_keyed_pool[]
         try (GenericKeyedObjectPool<Object, Object> p = createGenericKeyedObjectPool()) {
             Tags tagsToMatch = tags.and("type", "GenericKeyedObjectPool");
             commonsObjectPool2Metrics.bindTo(registry);
@@ -94,6 +100,7 @@ void verifyGenericKeyedObjectPoolMetricsWithExpectedTags() {
                         "commons.pool2.mean.borrow.wait")
                 .forEach(name -> registry.get(name).tags(tagsToMatch).timeGauge());
         }
+        // end::generic_keyed_pool[]
     }
 
     @Test