Removed Java 6 Optional workaround (prometheus#846)

Signed-off-by: Doug Hoard <[email protected]>

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

@@ -42,6 +42,7 @@
 import java.util.LinkedList;
 import java.util.List;
 import java.util.Map;
+import java.util.Optional;
 import java.util.Set;
 import java.util.TreeSet;
 import java.util.logging.Level;
@@ -70,7 +71,6 @@ void recordBean(
     private final boolean ssl;
     private final List<ObjectName> whitelistObjectNames, blacklistObjectNames;
     private final JmxMBeanPropertyCache jmxMBeanPropertyCache;
-    private final OptionalValueExtractor optionalValueExtractor = new OptionalValueExtractor();
 
     public JmxScraper(String jmxUrl, String username, String password, boolean ssl,
                       List<ObjectName> whitelistObjectNames, List<ObjectName> blacklistObjectNames,
@@ -347,16 +347,21 @@ private void processBeanValue(
             }
         } else if (value.getClass().isArray()) {
             logScrape(domain, "arrays are unsupported");
-        } else if (optionalValueExtractor.isOptional(value)) {
+        } else if (value instanceof Optional) {
             logScrape(domain + beanProperties + attrName, "java.util.Optional");
-            processBeanValue(
-                    domain,
-                    beanProperties,
-                    attrKeys,
-                    attrName,
-                    attrType,
-                    attrDescription,
-                    optionalValueExtractor.getOptionalValueOrNull(value));
+            Optional optional = (Optional) value;
+            if (optional.isPresent()) {
+                processBeanValue(
+                        domain,
+                        beanProperties,
+                        attrKeys,
+                        attrName,
+                        attrType,
+                        attrDescription,
+                        optional.get());
+            } else {
+                logScrape(domain + beanProperties + attrName, "java.util.Optional is empty");
+            }
         } else if (value.getClass().isEnum()) {
             logScrape(domain + beanProperties + attrName, value.toString());
             processBeanValue(

integration_test_suite/integration_tests/src/test/java/io/prometheus/jmx/test/OptionalValueMBeanTest.java

@@ -0,0 +1,45 @@
+/*
+ * Copyright (C) 2023 The Prometheus jmx_exporter Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.prometheus.jmx.test;
+
+import io.prometheus.jmx.test.support.ContentConsumer;
+import io.prometheus.jmx.test.support.MetricsRequest;
+import io.prometheus.jmx.test.support.MetricsResponse;
+import org.antublue.test.engine.api.TestEngine;
+
+import java.util.Collection;
+
+import static io.prometheus.jmx.test.support.RequestResponseAssertions.assertThatResponseForRequest;
+import static org.assertj.core.api.Assertions.assertThat;
+
+public class OptionalValueMBeanTest extends BaseTest {
+
+    @TestEngine.Test
+    public void testMetrics() {
+        assertThatResponseForRequest(new MetricsRequest(testState.httpClient()))
+                .isSuperset(MetricsResponse.RESULT_200)
+                .dispatch((ContentConsumer) content -> {
+                    Collection<Metric> metrics = MetricsParser.parse(content);
+                    metrics
+                            .forEach(metric -> {
+                                if (metric.getName().equals("io_prometheus_jmx_optionalValue_Value")) {
+                                    assertThat(metric.getValue()).isEqualTo(345.0);
+                                }
+                            });
+                });
+    }
+}

integration_test_suite/integration_tests/src/test/resources/io/prometheus/jmx/test/OptionalValueMBeanTest/JavaAgent/application.sh

@@ -0,0 +1,6 @@
+#!/bin/bash
+
+java \
+  -Xmx128M \
+  -javaagent:jmx_prometheus_javaagent.jar=8888:exporter.yaml \
+  -jar jmx_example_application.jar

integration_test_suite/integration_tests/src/test/resources/io/prometheus/jmx/test/OptionalValueMBeanTest/JavaAgent/exporter.yaml

@@ -0,0 +1,2 @@
+rules:
+  - pattern: ".*"

integration_test_suite/integration_tests/src/test/resources/io/prometheus/jmx/test/OptionalValueMBeanTest/Standalone/application.sh

@@ -0,0 +1,13 @@
+#!/bin/bash
+
+java \
+  -Xmx128M \
+  -Dcom.sun.management.jmxremote=true \
+  -Dcom.sun.management.jmxremote.authenticate=false \
+  -Dcom.sun.management.jmxremote.local.only=false \
+  -Dcom.sun.management.jmxremote.port=9999 \
+  -Dcom.sun.management.jmxremote.registry.ssl=false \
+  -Dcom.sun.management.jmxremote.rmi.port=9999 \
+  -Dcom.sun.management.jmxremote.ssl.need.client.auth=false \
+  -Dcom.sun.management.jmxremote.ssl=false \
+  -jar jmx_example_application.jar

integration_test_suite/integration_tests/src/test/resources/io/prometheus/jmx/test/OptionalValueMBeanTest/Standalone/exporter.sh

@@ -0,0 +1,5 @@
+#!/bin/bash
+
+java \
+  -Xmx128M \
+  -jar jmx_prometheus_httpserver.jar 8888 exporter.yaml

integration_test_suite/integration_tests/src/test/resources/io/prometheus/jmx/test/OptionalValueMBeanTest/Standalone/exporter.yaml

@@ -0,0 +1,3 @@
+hostPort: application:9999
+rules:
+  - pattern: ".*"

integration_test_suite/jmx_example_application/src/main/java/io/prometheus/jmx/JmxExampleApplication.java

@@ -39,6 +39,9 @@ public static void main(String[] args) throws Exception {
 
         ExistDb.registerBean(server);
 
+        ObjectName optionalValueMBean = new ObjectName("io.prometheus.jmx:type=optionalValue");
+        server.registerMBean(new OptionalValue(), optionalValueMBean);
+
         System.out.println(
                 String.format("%s | %s | INFO | %s | %s",
                         SIMPLE_DATE_FORMAT.format(new Date()),

integration_test_suite/jmx_example_application/src/main/java/io/prometheus/jmx/OptionalValueMBean.java

@@ -0,0 +1,38 @@
+/*
+ * Copyright (C) 2023 The Prometheus jmx_exporter Authors
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package io.prometheus.jmx;
+
+import java.util.Optional;
+
+public interface OptionalValueMBean {
+
+    Optional<Integer> getValue();
+}
+
+class OptionalValue implements OptionalValueMBean {
+
+    private final Integer VALUE = 345;
+
+    public OptionalValue() {
+        // DO NOTHING
+    }
+
+    @Override
+    public Optional<Integer> getValue() {
+        return Optional.of(VALUE);
+    }
+}