add testing, cosmetics

src/main/java/org/datadog/jmxfetch/reporter/Reporter.java

@@ -84,25 +84,26 @@ public void sendMetrics(LinkedList<HashMap<String, Object>> metrics, String inst
             // StatsD doesn't support rate metrics so we need to have our own aggregator to compute rates
             if ("gauge".equals(metricType) || "histogram".equals(metricType)) {
                 sendMetricPoint(metricType, metricName, currentValue, tags);
-            } else if ("gauge_delta".equals(metricType)) {
+            } else if ("count".equals(metricType)) {
                 String key = generateId(metric);
                 if (!instanceCountersAggregator.containsKey(key)) {
                     instanceCountersAggregator.put(key,  currentValue.longValue());
                     continue;
                 }
 
-                long oldValue =   instanceCountersAggregator.get(key);
-                long delta =  currentValue.longValue() - oldValue ;
+                long oldValue = instanceCountersAggregator.get(key);
+                long delta = currentValue.longValue() - oldValue;
 
-                boolean sane = (!Double.isNaN(delta) && !Double.isInfinite(delta));
-                boolean submit = (delta >= 0 || !canonicalRate);
+                if(Double.isNaN(delta) || Double.isInfinite(delta)) {
+                    continue;
+                }
 
-                if  (sane && submit) {
-                    sendMetricPoint(metricType, metricName, delta, tags);
-                } else if (sane) {
-                    LOGGER.info("Canonical rate option set, and negative delta (counter reset) - not submitting.");
+                if (delta < 0 && canonicalRate) {
+                    LOGGER.debug("Counter " + metricName + " has been reset and canonical rate is enabled - not submitting.");
+                    continue;
                 }
 
+                sendMetricPoint(metricType, metricName, delta, tags);
                 instanceCountersAggregator.put(key, currentValue.longValue());
             } else { // The metric should be 'counter'
                 String key = generateId(metric);
@@ -113,7 +114,6 @@ public void sendMetrics(LinkedList<HashMap<String, Object>> metrics, String inst
                     instanceRatesAggregator.put(key, rateInfo);
                     continue;
                 }
-                LOGGER.info("I SHOULD NOT BE HERE");
 
                 long oldTs = (Long) instanceRatesAggregator.get(key).get("ts");
                 double oldValue = (Double) instanceRatesAggregator.get(key).get(VALUE);

src/main/java/org/datadog/jmxfetch/reporter/StatsdReporter.java

@@ -31,7 +31,7 @@ protected void sendMetricPoint(String metricType, String metricName, double valu
             this.statsDClient.stop();
             init();
         }
-        if (metricType.equals("gauge_delta")) {
+        if (metricType.equals("count")) {
             statsDClient.count(metricName, (long) value, tags);
         } else if (metricType.equals("histogram")) {
             statsDClient.histogram(metricName, value, tags);

src/test/java/org/datadog/jmxfetch/TestApp.java

@@ -5,11 +5,7 @@
 import static org.junit.Assert.assertTrue;
 
 import java.io.File;
-import java.util.ArrayList;
-import java.util.Arrays;
-import java.util.HashMap;
-import java.util.LinkedList;
-import java.util.List;
+import java.util.*;
 
 import org.junit.Test;
 
@@ -715,6 +711,53 @@ public void testAppCanonicalRate() throws Exception {
         assertCoverage();
     }
 
+    /**
+     * Test counts.
+     *
+     */
+    @Test
+    public void testAppCount() throws Exception {
+        // We expose a few metrics through JMX
+        SimpleTestJavaApp testApp = new SimpleTestJavaApp();
+        registerMBean( testApp, "org.datadog.jmxfetch.test:type=SimpleTestJavaApp");
+
+        initApplication("jmx_count.yaml");
+
+        // First collection should not contain our count
+        run();
+        metrics = getMetrics();
+        assertEquals(13, metrics.size());
+
+        // Since our count is still equal to 0, we should report a delta equal to 0
+        run();
+        metrics = getMetrics();
+        assertEquals(14, metrics.size());
+        assertMetric("test.counter", 0, Collections.<String>emptyList(), 3);
+
+        // For the 3rd collection we increment the count to 5 so we should get a +5 delta
+        testApp.incrementCounter(5);
+        run();
+        metrics = getMetrics();
+        assertEquals(14, metrics.size());
+        assertMetric("test.counter", 5, Collections.<String>emptyList(), 3);
+
+        // For the 4th collection we decrement the count by 8 so we should get a -8 delta
+        testApp.decrementCounter(8);
+        run();
+        metrics = getMetrics();
+        assertEquals(14, metrics.size());
+        assertMetric("test.counter", -8, Collections.<String>emptyList(), 3);
+
+        // For the 5th collection we increment the count by 3 so we should get a +3 delta
+        testApp.incrementCounter(3);
+        run();
+        metrics = getMetrics();
+        assertEquals(14, metrics.size());
+        assertMetric("test.counter", 3, Collections.<String>emptyList(), 3);
+
+        assertCoverage();
+    }
+
     /**
      * Test JMX Service Discovery.
      *

src/test/resources/jmx_count.yaml

@@ -0,0 +1,13 @@
+init_config:
+
+instances:
+    -   process_name_regex: .*surefire.*
+        refresh_beans: 4
+        name: jmx_test_instance
+        conf:
+            - include:
+               domain: org.datadog.jmxfetch.test
+               attribute:
+                    ShouldBeCounter:
+                        metric_type: count
+                        alias: test.counter