jackson 2.16 changes some of its default settings so we consolidate our use of the ObjectMapper.

Unless special options are used, use a common instance, or create via factory metod.

16 files changed, 69 insertions, 88 deletions

diff --git a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericApplicationModel.java b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericApplicationModel.java
index a9ebd41fd36..59d1f9e5c83 100644
--- a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericApplicationModel.java
+++ b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericApplicationModel.java
@@ -4,7 +4,6 @@ package ai.vespa.metricsproxy.metric.model.json;
 import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonProperty;
-import com.fasterxml.jackson.databind.ObjectMapper;
 
 import java.io.IOException;
 import java.util.List;
@@ -22,9 +21,8 @@ public class GenericApplicationModel {
     public List<GenericJsonModel> nodes;
 
     public String serialize() {
-        ObjectMapper mapper = JacksonUtil.createObjectMapper();
         try {
-            return mapper.writeValueAsString(this);
+            return JacksonUtil.objectMapper().writeValueAsString(this);
         } catch (IOException e) {
             throw new JsonRenderingException("Could not render application nodes. Check the log for details.", e);
         }
diff --git a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonModel.java b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonModel.java
index ffb9813d257..c4ba0f39a18 100644
--- a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonModel.java
+++ b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonModel.java
@@ -5,7 +5,6 @@ import com.fasterxml.jackson.annotation.JsonIgnoreProperties;
 import com.fasterxml.jackson.annotation.JsonInclude;
 import com.fasterxml.jackson.annotation.JsonProperty;
 import com.fasterxml.jackson.annotation.JsonPropertyOrder;
-import com.fasterxml.jackson.databind.ObjectMapper;
 
 import java.io.IOException;
 import java.util.List;
@@ -33,9 +32,8 @@ public class GenericJsonModel {
     public List<GenericService> services;
 
     public String serialize() {
-        ObjectMapper mapper = JacksonUtil.createObjectMapper();
         try {
-            return mapper.writeValueAsString(this);
+            return JacksonUtil.objectMapper().writeValueAsString(this);
         } catch (IOException e) {
             throw new JsonRenderingException("Could not render metrics. Check the log for details.", e);
         }
diff --git a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonUtil.java b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonUtil.java
index 02f45010873..c32e90ecc9f 100644
--- a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonUtil.java
+++ b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonUtil.java
@@ -5,7 +5,6 @@ import ai.vespa.metricsproxy.http.application.Node;
 import ai.vespa.metricsproxy.metric.model.MetricsPacket;
 import ai.vespa.metricsproxy.metric.model.ServiceId;
 import ai.vespa.metricsproxy.metric.model.StatusCode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 
 import java.io.IOException;
 import java.util.ArrayList;
@@ -18,7 +17,7 @@ import java.util.stream.Collectors;
 import static ai.vespa.metricsproxy.metric.ExternalMetrics.VESPA_NODE_SERVICE_ID;
 import static ai.vespa.metricsproxy.metric.model.DimensionId.toDimensionId;
 import static ai.vespa.metricsproxy.metric.model.MetricId.toMetricId;
-import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.createObjectMapper;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static java.util.Collections.emptyList;
 import static java.util.Collections.singletonList;
 import static java.util.logging.Level.WARNING;
@@ -87,8 +86,7 @@ public class GenericJsonUtil {
 
     public static List<MetricsPacket.Builder> toMetricsPackets(String jsonString) {
         try {
-            ObjectMapper mapper = createObjectMapper();
-            GenericJsonModel jsonModel = mapper.readValue(jsonString, GenericJsonModel.class);
+            GenericJsonModel jsonModel = objectMapper().readValue(jsonString, GenericJsonModel.class);
             return toMetricsPackets(jsonModel);
         } catch (IOException e) {
             log.log(WARNING, "Could not create metrics packet from string:\n" + jsonString, e);
diff --git a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/JacksonUtil.java b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/JacksonUtil.java
index 72835a44e7f..8eb7df20218 100644
--- a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/JacksonUtil.java
+++ b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/JacksonUtil.java
@@ -1,6 +1,7 @@
 // Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package ai.vespa.metricsproxy.metric.model.json;
 
+import ai.vespa.json.Jackson;
 import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.Version;
 import com.fasterxml.jackson.databind.JsonSerializer;
@@ -22,6 +23,7 @@ public class JacksonUtil {
 
     private static final ThreadLocal<DecimalFormat> withinLongRangeFormat = ThreadLocal.withInitial(JacksonUtil::createWithinLongRangeFormat);
     private static final ThreadLocal<DecimalFormat> outsideLongRangeFormat = ThreadLocal.withInitial(JacksonUtil::createOutsideLongRangeFormat);
+    private static final ObjectMapper objectMapper = createObjectMapper();
     private static DecimalFormat createWithinLongRangeFormat() {
         DecimalFormat df = new DecimalFormat("#.####", new DecimalFormatSymbols(Locale.ENGLISH));
         df.setMaximumFractionDigits(13);
@@ -35,14 +37,17 @@ public class JacksonUtil {
     /**
      * Returns an object mapper with a custom floating point serializer to avoid scientific notation
      */
-    public static ObjectMapper createObjectMapper() {
-        ObjectMapper mapper = new ObjectMapper();
+    private static ObjectMapper createObjectMapper() {
+        ObjectMapper mapper = Jackson.createMapper();
         SimpleModule module = new SimpleModule("DoubleSerializer",
                                                new Version(1, 0, 0, "", null, null));
         module.addSerializer(Double.class, new DoubleSerializer());
         mapper.registerModule(module);
         return mapper;
     }
+    public static ObjectMapper objectMapper() {
+        return objectMapper;
+    }
     /**
      * Returns an object mapper with a custom floating point serializer to avoid scientific notation
      */
@@ -63,8 +68,8 @@ public class JacksonUtil {
     }
 
     public static class DoubleSerializer extends JsonSerializer<Double> {
-        private DecimalFormat withinLongRangeFormat = createWithinLongRangeFormat();
-        private DecimalFormat outsideLongRangeFormat = createOutsideLongRangeFormat();
+        private final DecimalFormat withinLongRangeFormat = createWithinLongRangeFormat();
+        private final DecimalFormat outsideLongRangeFormat = createOutsideLongRangeFormat();
         @Override
         public void serialize(Double value, JsonGenerator jgen, SerializerProvider provider) throws IOException {
             jgen.writeNumber(format(value, withinLongRangeFormat, outsideLongRangeFormat));
diff --git a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonUtil.java b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonUtil.java
index 6a88350d5ed..82049da5115 100644
--- a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonUtil.java
+++ b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonUtil.java
@@ -9,7 +9,6 @@ import com.fasterxml.jackson.core.JsonGenerator;
 import com.fasterxml.jackson.core.JsonParser;
 import com.fasterxml.jackson.core.StreamWriteFeature;
 import com.fasterxml.jackson.core.util.MinimalPrettyPrinter;
-import com.fasterxml.jackson.databind.ObjectMapper;
 
 import java.io.ByteArrayOutputStream;
 import java.io.IOException;
@@ -21,6 +20,7 @@ import java.util.logging.Logger;
 import java.util.stream.Collectors;
 
 import static ai.vespa.metricsproxy.http.ValuesFetcher.defaultMetricsConsumerId;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static java.util.Collections.emptyList;
 import static java.util.logging.Level.WARNING;
 
@@ -56,9 +56,8 @@ public class YamasJsonUtil {
      */
     public static List<MetricsPacket.Builder> toMetricsPackets(String jsonString) {
         List<MetricsPacket.Builder> packets = new ArrayList<>();
-        try {
-            JsonParser jp = new JsonFactory().createParser(jsonString);
-            jp.setCodec(new ObjectMapper());
+        var mapper = objectMapper();
+        try (JsonParser jp = mapper.createParser(jsonString)) {
             while (jp.nextToken() != null) {
                 YamasJsonModel jsonModel = jp.readValueAs(YamasJsonModel.class);
                 packets.add(toMetricsPacketBuilder(jsonModel));
diff --git a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/MetricsParser.java b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/MetricsParser.java
index 43011a24f8c..80ad2256b1c 100644
--- a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/MetricsParser.java
+++ b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/MetricsParser.java
@@ -1,6 +1,7 @@
 // Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package ai.vespa.metricsproxy.service;
 
+import ai.vespa.json.Jackson;
 import ai.vespa.metricsproxy.metric.Metric;
 import ai.vespa.metricsproxy.metric.model.DimensionId;
 import ai.vespa.metricsproxy.metric.model.MetricId;
@@ -31,14 +32,18 @@ public class MetricsParser {
         void accept(Metric metric);
     }
 
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
+    private static final ObjectMapper jsonMapper = Jackson.mapper();
 
     public static void parse(String data, Collector consumer) throws IOException {
-        parse(jsonMapper.createParser(data), consumer);
+        try (JsonParser parser = jsonMapper.createParser(data)) {
+            parse(parser, consumer);
+        }
     }
 
     static void parse(InputStream data, Collector consumer) throws IOException {
-        parse(jsonMapper.createParser(data), consumer);
+        try (JsonParser parser = jsonMapper.createParser(data)) {
+            parse(parser, consumer);
+        }
     }
 
     // Top level 'metrics' object, with e.g. 'time', 'status' and 'metrics'.
@@ -123,21 +128,19 @@ public class MetricsParser {
         for (parser.nextToken(); parser.getCurrentToken() != JsonToken.END_OBJECT; parser.nextToken()) {
             String fieldName = parser.getCurrentName();
             JsonToken token = parser.nextToken();
-            if (fieldName.equals("name")) {
-                name = parser.getText();
-            } else if (fieldName.equals("description")) {
-                description = parser.getText();
-            } else if (fieldName.equals("dimensions")) {
-                dim = parseDimensions(parser, uniqueDimensions);
-            } else if (fieldName.equals("values")) {
-                values = parseValues(parser);
-            } else {
-                if (token == JsonToken.START_OBJECT || token == JsonToken.START_ARRAY) {
-                    parser.skipChildren();
+            switch (fieldName) {
+                case "name" -> name = parser.getText();
+                case "description" -> description = parser.getText();
+                case "dimensions" -> dim = parseDimensions(parser, uniqueDimensions);
+                case "values" -> values = parseValues(parser);
+                default -> {
+                    if (token == JsonToken.START_OBJECT || token == JsonToken.START_ARRAY) {
+                        parser.skipChildren();
+                    }
                 }
             }
         }
-        if (name.equals("")) {
+        if (name.isEmpty()) {
             throw new IOException("missing name for entry in 'values' array");
         }
         for (Map.Entry<String, Number> value : values) {
diff --git a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/RemoteHealthMetricFetcher.java b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/RemoteHealthMetricFetcher.java
index b3ade5074b8..2f4a807a4d0 100644
--- a/metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/RemoteHealthMetricFetcher.java
+++ b/metrics-proxy/src/main/java/ai/vespa/metricsproxy/service/RemoteHealthMetricFetcher.java
@@ -1,9 +1,9 @@
 // Copyright Vespa.ai. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package ai.vespa.metricsproxy.service;
 
+import ai.vespa.json.Jackson;
 import ai.vespa.metricsproxy.metric.HealthMetric;
 import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import org.apache.hc.client5.http.impl.classic.CloseableHttpResponse;
 import org.apache.hc.core5.http.HttpEntity;
 import org.apache.hc.core5.http.io.entity.EntityUtils;
@@ -20,7 +20,6 @@ import java.util.logging.Logger;
  * @author Jo Kristian Bergum
  */
 public class RemoteHealthMetricFetcher extends HttpMetricFetcher {
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
     private final static Logger log = Logger.getLogger(RemoteHealthMetricFetcher.class.getPackage().getName());
 
     private final static String HEALTH_PATH = STATE_PATH + "health";
@@ -54,7 +53,7 @@ public class RemoteHealthMetricFetcher extends HttpMetricFetcher {
 
     private HealthMetric parse(InputStream data) {
         try {
-            JsonNode o = jsonMapper.readTree(data);
+            JsonNode o = Jackson.mapper().readTree(data);
             JsonNode status = o.get("status");
             String code = status.get("code").asText();
             String message = "";
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/application/ApplicationMetricsHandlerTest.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/application/ApplicationMetricsHandlerTest.java
index c57fe836269..3a902767f29 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/application/ApplicationMetricsHandlerTest.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/application/ApplicationMetricsHandlerTest.java
@@ -10,7 +10,6 @@ import ai.vespa.metricsproxy.metric.model.json.GenericJsonModel;
 import ai.vespa.metricsproxy.metric.model.json.GenericMetrics;
 import ai.vespa.metricsproxy.metric.model.json.GenericService;
 import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.github.tomakehurst.wiremock.junit.WireMockRule;
 import com.yahoo.container.jdisc.RequestHandlerTestDriver;
@@ -30,7 +29,7 @@ import static ai.vespa.metricsproxy.http.ValuesFetcher.defaultMetricsConsumerId;
 import static ai.vespa.metricsproxy.http.application.ApplicationMetricsHandler.METRICS_V1_PATH;
 import static ai.vespa.metricsproxy.http.application.ApplicationMetricsHandler.METRICS_VALUES_PATH;
 import static ai.vespa.metricsproxy.http.application.ApplicationMetricsHandler.PROMETHEUS_VALUES_PATH;
-import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.createObjectMapper;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static com.github.tomakehurst.wiremock.client.WireMock.aResponse;
 import static com.github.tomakehurst.wiremock.client.WireMock.equalTo;
 import static com.github.tomakehurst.wiremock.client.WireMock.get;
@@ -47,8 +46,6 @@ import static org.junit.Assert.fail;
  */
 public class ApplicationMetricsHandlerTest {
 
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
-
     private static final String HOST = "localhost";
     private static final String URI_BASE = "http://" + HOST;
     private static final String METRICS_V1_URI = URI_BASE + METRICS_V1_PATH;
@@ -105,7 +102,7 @@ public class ApplicationMetricsHandlerTest {
     @Test
     public void v1_response_contains_values_uri() throws Exception {
         String response = testDriver.sendRequest(METRICS_V1_URI).readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JsonNode root = objectMapper().readTree(response);
         assertTrue(root.has("resources"));
 
         ArrayNode resources = (ArrayNode) root.get("resources");
@@ -121,7 +118,7 @@ public class ApplicationMetricsHandlerTest {
     @Test
     public void visually_inspect_values_response_metrics() throws Exception {
         String response = testDriver.sendRequest(METRICS_VALUES_URI).readAll();
-        ObjectMapper mapper = createObjectMapper();
+        var mapper = objectMapper();
         var jsonModel = mapper.readValue(response, GenericApplicationModel.class);
         System.out.println(mapper.writerWithDefaultPrettyPrinter().writeValueAsString(jsonModel));
     }
@@ -202,14 +199,14 @@ public class ApplicationMetricsHandlerTest {
     @Test
     public void invalid_path_yields_error_response() throws Exception {
         String response = testDriver.sendRequest(METRICS_V1_URI + "/invalid").readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JsonNode root = objectMapper().readTree(response);
         assertTrue(root.has("error"));
     }
 
     private GenericApplicationModel getResponseAsJsonModel(String consumer) {
         String response = testDriver.sendRequest(METRICS_VALUES_URI + "?consumer=" + consumer).readAll();
         try {
-            return createObjectMapper().readValue(response, GenericApplicationModel.class);
+            return objectMapper().readValue(response, GenericApplicationModel.class);
         } catch (IOException e) {
             fail("Failed to create json model: " + e.getMessage());
             throw new RuntimeException(e);
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/metrics/MetricsHandlerTestBase.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/metrics/MetricsHandlerTestBase.java
index 692c4194bda..8e80dbddf9e 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/metrics/MetricsHandlerTestBase.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/metrics/MetricsHandlerTestBase.java
@@ -7,7 +7,6 @@ import ai.vespa.metricsproxy.metric.model.json.GenericMetrics;
 import ai.vespa.metricsproxy.metric.model.json.GenericService;
 import ai.vespa.metricsproxy.service.DownService;
 import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import org.junit.Ignore;
 import org.junit.Test;
@@ -19,7 +18,7 @@ import static ai.vespa.metricsproxy.metric.dimensions.PublicDimensions.INTERNAL_
 import static ai.vespa.metricsproxy.metric.dimensions.PublicDimensions.REASON;
 import static ai.vespa.metricsproxy.metric.dimensions.PublicDimensions.SERVICE_ID;
 import static ai.vespa.metricsproxy.metric.model.StatusCode.DOWN;
-import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.createObjectMapper;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static ai.vespa.metricsproxy.service.DummyService.METRIC_1;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertFalse;
@@ -33,8 +32,6 @@ import static org.junit.Assert.fail;
  */
 public abstract class MetricsHandlerTestBase<MODEL> extends HttpHandlerTestBase {
 
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
-
     static String rootUri;
     static String valuesUri;
 
@@ -45,7 +42,7 @@ public abstract class MetricsHandlerTestBase<MODEL> extends HttpHandlerTestBase
     private MODEL getResponseAsJsonModel(String consumer) {
         String response = testDriver.sendRequest(valuesUri + "?consumer=" + consumer).readAll();
         try {
-            return createObjectMapper().readValue(response, modelClass);
+            return objectMapper().readValue(response, modelClass);
         } catch (IOException e) {
             fail("Failed to create json model: " + e.getMessage());
             throw new RuntimeException(e);
@@ -59,14 +56,14 @@ public abstract class MetricsHandlerTestBase<MODEL> extends HttpHandlerTestBase
     @Test
     public void invalid_path_yields_error_response() throws Exception {
         String response = testDriver.sendRequest(rootUri + "/invalid").readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JsonNode root = objectMapper().readTree(response);
         assertTrue(root.has("error"));
     }
 
     @Test
     public void root_response_contains_values_uri() throws Exception {
         String response = testDriver.sendRequest(rootUri).readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JsonNode root = objectMapper().readTree(response);
         assertTrue(root.has("resources"));
 
         ArrayNode resources = (ArrayNode) root.get("resources");
@@ -80,7 +77,7 @@ public abstract class MetricsHandlerTestBase<MODEL> extends HttpHandlerTestBase
     @Test
     public void visually_inspect_values_response() throws Exception {
         String response = testDriver.sendRequest(valuesUri).readAll();
-        ObjectMapper mapper = createObjectMapper();
+        var mapper = objectMapper();
         var jsonModel = mapper.readValue(response, modelClass);
         System.out.println(mapper.writerWithDefaultPrettyPrinter().writeValueAsString(jsonModel));
     }
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/prometheus/PrometheusHandlerTest.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/prometheus/PrometheusHandlerTest.java
index f8e07c3f2ec..b36f521e4ac 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/prometheus/PrometheusHandlerTest.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/http/prometheus/PrometheusHandlerTest.java
@@ -4,7 +4,6 @@ package ai.vespa.metricsproxy.http.prometheus;
 import ai.vespa.metricsproxy.http.HttpHandlerTestBase;
 import ai.vespa.metricsproxy.service.DummyService;
 import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.yahoo.container.jdisc.RequestHandlerTestDriver;
 import org.junit.BeforeClass;
@@ -14,17 +13,15 @@ import org.junit.Test;
 import java.util.concurrent.Executors;
 
 import static ai.vespa.metricsproxy.metric.dimensions.PublicDimensions.REASON;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
 
 /**
  * @author gjoranv
  */
-@SuppressWarnings("UnstableApiUsage")
 public class PrometheusHandlerTest extends HttpHandlerTestBase {
 
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
-
     private static final String V1_URI = URI_BASE + PrometheusHandler.V1_PATH;
     private static final String VALUES_URI = URI_BASE + PrometheusHandler.VALUES_PATH;
 
@@ -45,7 +42,7 @@ public class PrometheusHandlerTest extends HttpHandlerTestBase {
     @Test
     public void v1_response_contains_values_uri() throws Exception {
         String response = testDriver.sendRequest(V1_URI).readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JsonNode root = objectMapper().readTree(response);
         assertTrue(root.has("resources"));
 
         ArrayNode resources = (ArrayNode) root.get("resources");
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/GenericApplicationModelTest.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/GenericApplicationModelTest.java
index f773a1095cd..54736851b3f 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/GenericApplicationModelTest.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/GenericApplicationModelTest.java
@@ -4,7 +4,6 @@ package ai.vespa.metricsproxy.metric.model.json;
 import ai.vespa.metricsproxy.http.application.Node;
 import ai.vespa.metricsproxy.metric.model.MetricsPacket;
 import ai.vespa.metricsproxy.metric.model.StatusCode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -16,7 +15,7 @@ import static ai.vespa.metricsproxy.metric.ExternalMetrics.VESPA_NODE_SERVICE_ID
 import static ai.vespa.metricsproxy.metric.model.DimensionId.toDimensionId;
 import static ai.vespa.metricsproxy.metric.model.MetricId.toMetricId;
 import static ai.vespa.metricsproxy.metric.model.ServiceId.toServiceId;
-import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.createObjectMapper;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 
@@ -90,7 +89,7 @@ public class GenericApplicationModelTest {
         assertEquals("service-dim-value", serviceMetrics.dimensions.get("service-dim"));
 
         // Visual inspection
-        System.out.println(createObjectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(nodeModel));
+        System.out.println(objectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(nodeModel));
     }
 
     private MetricsPacket createMetricsPacket(String service, Number metricsValue, boolean isNode) {
@@ -112,8 +111,7 @@ public class GenericApplicationModelTest {
     }
 
     private static GenericApplicationModel genericJsonModelFromTestFile() throws IOException {
-        ObjectMapper mapper = createObjectMapper();
-        return mapper.readValue(getFileContents(TEST_FILE), GenericApplicationModel.class);
+        return objectMapper().readValue(getFileContents(TEST_FILE), GenericApplicationModel.class);
     }
 
 }
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonModelTest.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonModelTest.java
index cdcd049ecfc..9eb1ed8cd5a 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonModelTest.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/GenericJsonModelTest.java
@@ -3,7 +3,6 @@ package ai.vespa.metricsproxy.metric.model.json;
 
 import ai.vespa.metricsproxy.metric.model.MetricsPacket;
 import ai.vespa.metricsproxy.metric.model.StatusCode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import org.junit.Test;
 
 import java.io.IOException;
@@ -14,7 +13,7 @@ import static ai.vespa.metricsproxy.metric.ExternalMetrics.VESPA_NODE_SERVICE_ID
 import static ai.vespa.metricsproxy.metric.model.DimensionId.toDimensionId;
 import static ai.vespa.metricsproxy.metric.model.MetricId.toMetricId;
 import static ai.vespa.metricsproxy.metric.model.ServiceId.toServiceId;
-import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.createObjectMapper;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNotNull;
 
@@ -113,7 +112,7 @@ public class GenericJsonModelTest {
         assertEquals("service-dim-value", serviceMetrics.dimensions.get("service-dim"));
 
         // Visual inspection
-        System.out.println(createObjectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(jsonModel));
+        System.out.println(objectMapper().writerWithDefaultPrettyPrinter().writeValueAsString(jsonModel));
     }
 
     @Test
@@ -138,8 +137,7 @@ public class GenericJsonModelTest {
     }
 
     private GenericJsonModel genericJsonModelFromTestFile(String filename) throws IOException {
-        ObjectMapper mapper = createObjectMapper();
-        return mapper.readValue(getFileContents(filename), GenericJsonModel.class);
+        return objectMapper().readValue(getFileContents(filename), GenericJsonModel.class);
     }
 
     @Test
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonModelTest.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonModelTest.java
index ae0f79746e5..8f3a99c1c68 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonModelTest.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonModelTest.java
@@ -16,6 +16,7 @@ import java.util.List;
 import static ai.vespa.metricsproxy.metric.model.ConsumerId.toConsumerId;
 import static ai.vespa.metricsproxy.metric.model.MetricId.toMetricId;
 import static ai.vespa.metricsproxy.metric.model.ServiceId.toServiceId;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertNull;
 import static org.junit.Assert.assertTrue;
@@ -78,8 +79,7 @@ public class YamasJsonModelTest {
         // Read file that was taken from production (real -life example that is)
         String filename = getClass().getClassLoader().getResource("yamas-array-no-routing.json").getFile();
         BufferedReader reader = Files.newBufferedReader(Paths.get(filename));
-        ObjectMapper mapper = new ObjectMapper();
-        YamasJsonModel jsonModel = mapper.readValue(reader, YamasJsonModel.class);
+        YamasJsonModel jsonModel = objectMapper().readValue(reader, YamasJsonModel.class);
 
         // Do some sanity checking
         assertNull(jsonModel.routing);
@@ -104,8 +104,7 @@ public class YamasJsonModelTest {
     private YamasJsonModel getYamasJsonModel(String testFile) throws IOException {
         String filename = getClass().getClassLoader().getResource(testFile).getFile();
         BufferedReader reader = Files.newBufferedReader(Paths.get(filename));
-        ObjectMapper mapper = new ObjectMapper();
-        return mapper.readValue(reader, YamasJsonModel.class);
+        return objectMapper().readValue(reader, YamasJsonModel.class);
     }
 
 }
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonUtilTest.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonUtilTest.java
index 7281c674745..aa85277b3b7 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonUtilTest.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/metric/model/json/YamasJsonUtilTest.java
@@ -3,7 +3,6 @@ package ai.vespa.metricsproxy.metric.model.json;
 
 import ai.vespa.metricsproxy.metric.model.MetricsPacket;
 import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import org.junit.Test;
 
@@ -14,6 +13,7 @@ import java.util.Set;
 import static ai.vespa.metricsproxy.core.VespaMetrics.vespaMetricsConsumerId;
 import static ai.vespa.metricsproxy.http.ValuesFetcher.defaultMetricsConsumerId;
 import static ai.vespa.metricsproxy.metric.model.ServiceId.toServiceId;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static ai.vespa.metricsproxy.metric.model.json.YamasJsonUtil.YAMAS_ROUTING;
 import static ai.vespa.metricsproxy.metric.model.json.YamasJsonUtil.toMetricsPackets;
 import static org.junit.Assert.assertEquals;
@@ -24,12 +24,11 @@ import static org.junit.Assert.assertTrue;
  * @author gjoranv
  */
 public class YamasJsonUtilTest {
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
     private static JsonNode metrics(MetricsPacket packet, boolean addStatus) throws IOException {
         return metrics(List.of(packet), addStatus).get(0);
     }
     private static ArrayNode metrics(List<MetricsPacket> packets, boolean addStatus) throws IOException {
-        return (ArrayNode) jsonMapper.readTree(YamasJsonUtil.toJson(packets, addStatus)).get("metrics");
+        return (ArrayNode) objectMapper().readTree(YamasJsonUtil.toJson(packets, addStatus)).get("metrics");
     }
 
     @Test
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/node/NodeMetricGathererTest.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/node/NodeMetricGathererTest.java
index b67967b7e04..20164b91a55 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/node/NodeMetricGathererTest.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/node/NodeMetricGathererTest.java
@@ -5,7 +5,6 @@ import ai.vespa.metricsproxy.metric.model.ConsumerId;
 import ai.vespa.metricsproxy.metric.model.MetricId;
 import ai.vespa.metricsproxy.metric.model.MetricsPacket;
 import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ObjectNode;
 import org.junit.Test;
 
@@ -13,6 +12,7 @@ import java.util.ArrayList;
 import java.util.List;
 import java.util.Set;
 
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static org.junit.Assert.assertEquals;
 
 /**
@@ -20,8 +20,6 @@ import static org.junit.Assert.assertEquals;
  */
 public class NodeMetricGathererTest {
 
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
-
     @Test
     public void testJSONObjectIsCorrectlyConvertedToMetricsPacket() {
         List<MetricsPacket.Builder> builders = new ArrayList<>();
@@ -31,17 +29,17 @@ public class NodeMetricGathererTest {
 
         assertEquals("host_life", packet.service.id);
         assertEquals(123, packet.timestamp);
-        assertEquals(12l, packet.metrics().get(MetricId.toMetricId("uptime")));
-        assertEquals(1l, packet.metrics().get(MetricId.toMetricId("alive")));
+        assertEquals(12L, packet.metrics().get(MetricId.toMetricId("uptime")));
+        assertEquals(1L, packet.metrics().get(MetricId.toMetricId("alive")));
         assertEquals(Set.of(ConsumerId.toConsumerId("Vespa")), packet.consumers());
     }
 
     private JsonNode generateHostLifePacket() {
 
-        ObjectNode jsonObject = jsonMapper.createObjectNode();
+        ObjectNode jsonObject = objectMapper().createObjectNode();
         jsonObject.put("timestamp", 123);
         jsonObject.put("application", "host_life");
-        ObjectNode metrics = jsonMapper.createObjectNode();
+        ObjectNode metrics = objectMapper().createObjectNode();
         metrics.put("uptime", 12);
         metrics.put("alive", 1);
         jsonObject.set("metrics", metrics);
diff --git a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/rpc/RpcMetricsTest.java b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/rpc/RpcMetricsTest.java
index 0b333db3c71..e6c3ca20e00 100644
--- a/metrics-proxy/src/test/java/ai/vespa/metricsproxy/rpc/RpcMetricsTest.java
+++ b/metrics-proxy/src/test/java/ai/vespa/metricsproxy/rpc/RpcMetricsTest.java
@@ -6,7 +6,6 @@ import ai.vespa.metricsproxy.metric.Metrics;
 import ai.vespa.metricsproxy.metric.model.ConsumerId;
 import ai.vespa.metricsproxy.service.VespaService;
 import com.fasterxml.jackson.databind.JsonNode;
-import com.fasterxml.jackson.databind.ObjectMapper;
 import com.fasterxml.jackson.databind.node.ArrayNode;
 import com.yahoo.jrt.Request;
 import com.yahoo.jrt.Spec;
@@ -26,6 +25,7 @@ import static ai.vespa.metricsproxy.TestUtil.getFileContents;
 import static ai.vespa.metricsproxy.core.VespaMetrics.vespaMetricsConsumerId;
 import static ai.vespa.metricsproxy.metric.model.DimensionId.toDimensionId;
 import static ai.vespa.metricsproxy.metric.model.MetricId.toMetricId;
+import static ai.vespa.metricsproxy.metric.model.json.JacksonUtil.objectMapper;
 import static ai.vespa.metricsproxy.rpc.IntegrationTester.CUSTOM_CONSUMER_ID;
 import static ai.vespa.metricsproxy.rpc.IntegrationTester.MONITORING_SYSTEM;
 import static ai.vespa.metricsproxy.rpc.IntegrationTester.SERVICE_1_CONFIG_ID;
@@ -42,8 +42,6 @@ import static org.junit.Assert.assertTrue;
  */
 public class RpcMetricsTest {
 
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
-
     private static final String METRICS_RESPONSE = getFileContents("metrics-storage-simple.json").trim();
     private static final String EXTRA_APP = "extra";
     private static final Duration RPC_INVOKE_TIMEOUT = Duration.ofSeconds(60);
@@ -148,7 +146,7 @@ public class RpcMetricsTest {
 
     private static void verifyMetricsFromRpcRequest(VespaService service, RpcClient client) throws IOException {
         String jsonResponse = getMetricsForYamas(service.getMonitoringName().id, client).trim();
-        ArrayNode metrics = (ArrayNode) jsonMapper.readTree(jsonResponse).get("metrics");
+        ArrayNode metrics = (ArrayNode) objectMapper().readTree(jsonResponse).get("metrics");
         assertEquals("Expected 3 metric messages", 3, metrics.size());
         for (int i = 0; i < metrics.size() - 1; i++) { // The last "metric message" contains only status code/message
             JsonNode jsonObject = metrics.get(i);
@@ -184,7 +182,7 @@ public class RpcMetricsTest {
     private void verifyMetricsFromRpcRequestForAllServices(RpcClient client) throws IOException {
         // Verify that metrics for all services can be retrieved in one request.
         String allServicesResponse = getMetricsForYamas(ALL_SERVICES, client).trim();
-        ArrayNode allServicesMetrics = (ArrayNode) jsonMapper.readTree(allServicesResponse).get("metrics");
+        ArrayNode allServicesMetrics = (ArrayNode) objectMapper().readTree(allServicesResponse).get("metrics");
         assertEquals(5, allServicesMetrics.size());
     }
 
@@ -221,13 +219,13 @@ public class RpcMetricsTest {
     }
 
     private JsonNode findExtraMetricsObject(String jsonResponse) throws IOException {
-        ArrayNode metrics = (ArrayNode) jsonMapper.readTree(jsonResponse).get("metrics");
+        ArrayNode metrics = (ArrayNode) objectMapper().readTree(jsonResponse).get("metrics");
         for (int i = 0; i <  metrics.size(); i++) {
             JsonNode jsonObject = metrics.get(i);
             assertTrue(jsonObject.has("application"));
             if (jsonObject.get("application").textValue().equals(EXTRA_APP)) return jsonObject;
         }
-        return jsonMapper.createObjectNode();
+        return objectMapper().createObjectNode();
     }
 
     private static String getMetricsForYamas(String service, RpcClient client) {