added support on jmx attributes of type java.util.Date

collector/src/main/java/io/prometheus/jmx/JmxScraper.java

@@ -190,7 +190,11 @@ private void processBeanValue(
             Object value) {
         if (value == null) {
             logScrape(domain + beanProperties + attrName, "null");
-        } else if (value instanceof Number || value instanceof String || value instanceof Boolean) {
+        } else if (value instanceof Number || value instanceof String || value instanceof Boolean || value instanceof java.util.Date) {
+            if (value instanceof java.util.Date) {
+                attrType = "java.lang.Double";
+                value = ((java.util.Date) value).getTime() / 1000.0;
+            }
             logScrape(domain + beanProperties + attrName, value.toString());
             this.receiver.recordBean(
                     domain,

collector/src/test/java/io/prometheus/jmx/CamelMBean.java

@@ -0,0 +1,26 @@
+package io.prometheus.jmx;
+
+import javax.management.MBeanServer;
+import javax.management.ObjectName;
+import java.util.Date;
+
+public interface CamelMBean {
+  double EXPECTED_SECONDS = 1.573285945111E9;
+
+  Date getLastExchangeFailureTimestamp();
+}
+
+class Camel implements CamelMBean {
+  public static void registerBean(MBeanServer mbs)
+          throws javax.management.JMException {
+    ObjectName mbeanName = new ObjectName(
+            "org.apache.camel:context=my-camel-context,type=routes,name=\"my-route-name\"");
+    Camel mbean = new Camel();
+    mbs.registerMBean(mbean, mbeanName);
+  }
+
+  @Override
+  public Date getLastExchangeFailureTimestamp() {
+    return new Date((long)(EXPECTED_SECONDS * 1000));
+  }
+}

collector/src/test/java/io/prometheus/jmx/JmxCollectorTest.java

@@ -31,6 +31,7 @@ public static void OneTimeSetUp() throws Exception {
 
         TomcatServlet.registerBean(mbs);
         Bool.registerBean(mbs);
+        Camel.registerBean(mbs);
     }
 
     @Before
@@ -252,4 +253,20 @@ public void testDelayedStartReady() throws Exception {
       Thread.sleep(2000);
       assertEquals(1.0, registry.getSampleValue("boolean_Test_True", new String[]{}, new String[]{}), .001);
     }
+
+    @Test
+    public void testCamelLastExchangFailureTimestamp() throws Exception{
+      String rulePattern =
+              "\n---\nrules:\n- pattern: 'org.apache.camel<context=([^,]+), type=routes, name=\"([^\"]+)\"><>LastExchangeFailureTimestamp'\n" +
+                      "  name: org.apache.camel.LastExchangeFailureTimestamp\n" +
+                      "  help: Exchanges Last Failure Timestamps\n" +
+                      "  type: UNTYPED\n" +
+                      "  labels:\n" +
+                      "    context: \"$1\"\n" +
+                      "    route: \"$2\"\n" +
+                      "    type: routes";
+      JmxCollector jc = new JmxCollector(rulePattern).register(registry);
+      Double actual = registry.getSampleValue("org_apache_camel_LastExchangeFailureTimestamp", new String[]{"context", "route", "type"}, new String[]{"my-camel-context", "my-route-name", "routes"});
+      assertEquals(Camel.EXPECTED_SECONDS, actual, 0);
+    }
 }