Remove usage of org.json

8 files changed, 161 insertions, 214 deletions

diff --git a/container-core/src/main/java/com/yahoo/container/handler/metrics/HttpHandlerBase.java b/container-core/src/main/java/com/yahoo/container/handler/metrics/HttpHandlerBase.java
index 92840cee48f..8c902f88e38 100644
--- a/container-core/src/main/java/com/yahoo/container/handler/metrics/HttpHandlerBase.java
+++ b/container-core/src/main/java/com/yahoo/container/handler/metrics/HttpHandlerBase.java
@@ -1,13 +1,14 @@
 // Copyright 2020 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.container.handler.metrics;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.yahoo.container.jdisc.HttpRequest;
 import com.yahoo.container.jdisc.HttpResponse;
 import com.yahoo.container.jdisc.ThreadedHttpRequestHandler;
 import com.yahoo.restapi.Path;
-import org.json.JSONArray;
-import org.json.JSONException;
-import org.json.JSONObject;
 
 import java.net.URI;
 import java.util.List;
@@ -26,6 +27,8 @@ import static java.util.logging.Level.WARNING;
  */
 public abstract class HttpHandlerBase extends ThreadedHttpRequestHandler {
 
+    private static final ObjectMapper jsonMapper = new ObjectMapper();
+
     protected HttpHandlerBase(Executor executor) {
         super(executor);
     }
@@ -49,15 +52,14 @@ public abstract class HttpHandlerBase extends ThreadedHttpRequestHandler {
     protected JsonResponse resourceListResponse(URI requestUri, List<String> resources) {
         try {
             return new JsonResponse(OK, resourceList(requestUri, resources));
-        } catch (JSONException e) {
+        } catch (JsonProcessingException e) {
             log.log(WARNING, "Bad JSON construction in generated resource list for " + requestUri.getPath(), e);
             return new ErrorResponse(INTERNAL_SERVER_ERROR,
                                      "An error occurred when generating the list of api resources.");
         }
     }
 
-    // TODO: Use jackson with a "Resources" class instead of JSONObject
-    private static String resourceList(URI requestUri, List<String> resources) throws JSONException {
+    private static String resourceList(URI requestUri, List<String> resources) throws JsonProcessingException {
         int port = requestUri.getPort();
         String host = requestUri.getHost();
         StringBuilder base = new StringBuilder("http://");
@@ -66,13 +68,14 @@ public abstract class HttpHandlerBase extends ThreadedHttpRequestHandler {
             base.append(":").append(port);
         }
         String uriBase = base.toString();
-        JSONArray linkList = new JSONArray();
+        ArrayNode linkList = jsonMapper.createArrayNode();
         for (String api : resources) {
-            JSONObject resource = new JSONObject();
+            ObjectNode resource = jsonMapper.createObjectNode();
             resource.put("url", uriBase + api);
-            linkList.put(resource);
+            linkList.add(resource);
         }
-        return new JSONObject().put("resources", linkList).toString(4);
+        return jsonMapper.writerWithDefaultPrettyPrinter()
+                .writeValueAsString(jsonMapper.createObjectNode().set("resources", linkList));
     }
 
 }
diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/CoredumpGatherer.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/CoredumpGatherer.java
index d105eaa9d98..f1ef7894511 100644
--- a/container-core/src/main/java/com/yahoo/container/jdisc/state/CoredumpGatherer.java
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/CoredumpGatherer.java
@@ -1,17 +1,16 @@
 // Copyright 2019 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.container.jdisc.state;
 
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.yahoo.vespa.defaults.Defaults;
-import org.json.JSONException;
-import org.json.JSONObject;
 
 import java.io.IOException;
 import java.io.UncheckedIOException;
-import java.nio.file.Files;
 import java.nio.file.NoSuchFileException;
 import java.nio.file.Path;
 import java.time.Instant;
-import java.util.Set;
 import java.util.stream.Stream;
 
 /**
@@ -19,19 +18,17 @@ import java.util.stream.Stream;
  */
 public class CoredumpGatherer {
 
+    private static final ObjectMapper jsonMapper = new ObjectMapper();
+
     private static final Path COREDUMP_PATH = Path.of(Defaults.getDefaults().underVespaHome("var/crash/processing"));
 
-    public static JSONObject gatherCoredumpMetrics(FileWrapper fileWrapper) {
+    public static JsonNode gatherCoredumpMetrics(FileWrapper fileWrapper) {
         int coredumps = getNumberOfCoredumps(fileWrapper);
-        JSONObject packet = new JSONObject();
-
-        try {
-            packet.put("status_code", coredumps == 0 ? 0 : 1);
-            packet.put("status_msg", coredumps == 0 ? "OK" : String.format("Found %d coredump(s)", coredumps));
-            packet.put("timestamp", Instant.now().getEpochSecond());
-            packet.put("application", "system-coredumps-processing");
-
-        } catch (JSONException e) {}
+        ObjectNode packet = jsonMapper.createObjectNode();
+        packet.put("status_code", coredumps == 0 ? 0 : 1);
+        packet.put("status_msg", coredumps == 0 ? "OK" : String.format("Found %d coredump(s)", coredumps));
+        packet.put("timestamp", Instant.now().getEpochSecond());
+        packet.put("application", "system-coredumps-processing");
         return packet;
     }
 
diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/HostLifeGatherer.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/HostLifeGatherer.java
index 730f7bc13cd..28f99096d84 100644
--- a/container-core/src/main/java/com/yahoo/container/jdisc/state/HostLifeGatherer.java
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/HostLifeGatherer.java
@@ -1,8 +1,9 @@
 // Copyright 2019 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.container.jdisc.state;
 
-import org.json.JSONException;
-import org.json.JSONObject;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ObjectNode;
 
 import java.io.IOException;
 import java.nio.file.Path;
@@ -13,9 +14,11 @@ import java.time.Instant;
  */
 public class HostLifeGatherer {
 
+    private static final ObjectMapper jsonMapper = new ObjectMapper();
+
     private static final Path UPTIME_PATH = Path.of("/proc");
 
-    public static JSONObject getHostLifePacket(FileWrapper fileWrapper) {
+    public static JsonNode getHostLifePacket(FileWrapper fileWrapper) {
         long upTime;
         int statusCode = 0;
         String statusMessage = "OK";
@@ -29,19 +32,15 @@ public class HostLifeGatherer {
         }
 
 
-        JSONObject jsonObject = new JSONObject();
-        try {
-            jsonObject.put("status_code", statusCode);
-            jsonObject.put("status_msg", statusMessage);
-            jsonObject.put("timestamp", Instant.now().getEpochSecond());
-            jsonObject.put("application", "host_life");
-            JSONObject metrics = new JSONObject();
-            metrics.put("uptime", upTime);
-            metrics.put("alive", 1);
-            jsonObject.put("metrics", metrics);
-
-        } catch (JSONException e) {}
-
+        ObjectNode jsonObject = jsonMapper.createObjectNode();
+        jsonObject.put("status_code", statusCode);
+        jsonObject.put("status_msg", statusMessage);
+        jsonObject.put("timestamp", Instant.now().getEpochSecond());
+        jsonObject.put("application", "host_life");
+        ObjectNode metrics = jsonMapper.createObjectNode();
+        metrics.put("uptime", upTime);
+        metrics.put("alive", 1);
+        jsonObject.set("metrics", metrics);
         return jsonObject;
     }
 
diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/JSONObjectWithLegibleException.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/JSONObjectWithLegibleException.java
deleted file mode 100644
index d22dd9d6f4b..00000000000
--- a/container-core/src/main/java/com/yahoo/container/jdisc/state/JSONObjectWithLegibleException.java
+++ /dev/null
@@ -1,87 +0,0 @@
-// Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
-package com.yahoo.container.jdisc.state;
-
-import org.json.JSONException;
-import org.json.JSONObject;
-
-import java.util.Collection;
-import java.util.Map;
-
-/**
- * A JSONObject that wraps the checked JSONException in a RuntimeException with a legible error message.
- *
- * @author gjoranv
- */
-class JSONObjectWithLegibleException extends JSONObject {
-
-    @Override
-    public JSONObject put(String s, boolean b) {
-        try {
-            return super.put(s, b);
-        } catch (JSONException e) {
-            throw new RuntimeException(getErrorMessage(s, b, e), e);
-        }
-    }
-
-    @Override
-    public JSONObject put(String s, double v) {
-        try {
-            Double guardedVal = (((Double) v).isNaN() || ((Double) v).isInfinite()) ?
-                    0.0 : v;
-            return super.put(s, guardedVal);
-        } catch (JSONException e) {
-            throw new RuntimeException(getErrorMessage(s, v, e), e);
-        }
-    }
-
-    @Override
-    public JSONObject put(String s, int i) {
-        try {
-            return super.put(s, i);
-        } catch (JSONException e) {
-            throw new RuntimeException(getErrorMessage(s, i, e), e);
-        }
-    }
-
-    @Override
-    public JSONObject put(String s, long l) {
-        try {
-            return super.put(s, l);
-        } catch (JSONException e) {
-            throw new RuntimeException(getErrorMessage(s, l, e), e);
-        }
-    }
-
-    @Override
-    public JSONObject put(String s, Collection collection) {
-        try {
-            return super.put(s, collection);
-        } catch (JSONException e) {
-            throw new RuntimeException(getErrorMessage(s, collection, e), e);
-        }
-    }
-
-    @Override
-    public JSONObject put(String s, Map map) {
-        try {
-            return super.put(s, map);
-        } catch (JSONException e) {
-            throw new RuntimeException(getErrorMessage(s, map, e), e);
-        }
-    }
-
-    @Override
-    public JSONObject put(String s, Object o) {
-        try {
-            return super.put(s, o);
-        } catch (JSONException e) {
-            throw new RuntimeException(getErrorMessage(s, o, e), e);
-        }
-    }
-
-    private String getErrorMessage(String key, Object value, JSONException e) {
-        return "Trying to add invalid JSON object with key '" + key +
-                "' and value '" + value + "' - " + e.getMessage();
-    }
-
-}
diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/JsonUtil.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/JsonUtil.java
new file mode 100644
index 00000000000..4c697fb5ada
--- /dev/null
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/JsonUtil.java
@@ -0,0 +1,15 @@
+// Copyright Verizon Media. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
+package com.yahoo.container.jdisc.state;
+
+/**
+ * @author bjorncs
+ */
+class JsonUtil {
+
+    private JsonUtil() {}
+
+    static double sanitizeDouble(double value) {
+        return (((Double) value).isNaN() || ((Double) value).isInfinite()) ? 0.0 : value;
+    }
+
+}
diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricGatherer.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricGatherer.java
index 6a06a6362f5..add69403455 100644
--- a/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricGatherer.java
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricGatherer.java
@@ -1,7 +1,7 @@
 // Copyright 2019 Oath Inc. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.container.jdisc.state;
 
-import org.json.JSONObject;
+import com.fasterxml.jackson.databind.JsonNode;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -13,9 +13,9 @@ import java.util.List;
  */
 public class MetricGatherer {
 
-    static List<JSONObject> getAdditionalMetrics() {
+    static List<JsonNode> getAdditionalMetrics() {
         FileWrapper fileWrapper = new FileWrapper();
-        List<JSONObject> packetList = new ArrayList<>();
+        List<JsonNode> packetList = new ArrayList<>();
         packetList.add(CoredumpGatherer.gatherCoredumpMetrics(fileWrapper));
         if (System.getProperty("os.name").contains("nux"))
             packetList.add(HostLifeGatherer.getHostLifePacket(fileWrapper));
diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricsPacketsHandler.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricsPacketsHandler.java
index 3d3f0e4b677..824323af3d6 100644
--- a/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricsPacketsHandler.java
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricsPacketsHandler.java
@@ -1,6 +1,11 @@
 // Copyright 2018 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.container.jdisc.state;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.inject.Inject;
 import com.yahoo.collections.Tuple2;
 import com.yahoo.component.provider.ComponentRegistry;
@@ -13,9 +18,6 @@ import com.yahoo.jdisc.handler.ResponseDispatch;
 import com.yahoo.jdisc.handler.ResponseHandler;
 import com.yahoo.jdisc.http.HttpHeaders;
 import com.yahoo.metrics.MetricsPresentationConfig;
-import org.json.JSONArray;
-import org.json.JSONException;
-import org.json.JSONObject;
 
 import java.nio.ByteBuffer;
 import java.nio.charset.StandardCharsets;
@@ -26,6 +28,7 @@ import java.util.List;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
 
+import static com.yahoo.container.jdisc.state.JsonUtil.sanitizeDouble;
 import static com.yahoo.container.jdisc.state.StateHandler.getSnapshotPreprocessor;
 
 /**
@@ -44,6 +47,8 @@ import static com.yahoo.container.jdisc.state.StateHandler.getSnapshotPreprocess
  */
 public class MetricsPacketsHandler extends AbstractRequestHandler {
 
+    private static final ObjectMapper jsonMapper = new ObjectMapper();
+
     static final String APPLICATION_KEY = "application";
     static final String TIMESTAMP_KEY   = "timestamp";
     static final String STATUS_CODE_KEY = "status_code";
@@ -97,19 +102,19 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
             }
             String output = jsonToString(getStatusPacket()) + getAllMetricsPackets() + "\n";
             return output.getBytes(StandardCharsets.UTF_8);
-        } catch (JSONException e) {
+        } catch (JsonProcessingException e) {
             throw new RuntimeException("Bad JSON construction.", e);
         }
     }
 
-    private byte[] getMetricsArray() throws JSONException {
-        JSONObject root = new JSONObject();
-        JSONArray jsonArray = new JSONArray();
-        jsonArray.put(getStatusPacket());
+    private byte[] getMetricsArray() throws JsonProcessingException {
+        ObjectNode root = jsonMapper.createObjectNode();
+        ArrayNode jsonArray = jsonMapper.createArrayNode();
+        jsonArray.add(getStatusPacket());
         getPacketsForSnapshot(getSnapshot(), applicationName, timer.currentTimeMillis())
-                .forEach(jsonArray::put);
-        MetricGatherer.getAdditionalMetrics().forEach(jsonArray::put);
-        root.put("metrics", jsonArray);
+                .forEach(jsonArray::add);
+        MetricGatherer.getAdditionalMetrics().forEach(jsonArray::add);
+        root.set("metrics", jsonArray);
         return jsonToString(root)
                 .getBytes(StandardCharsets.UTF_8);
     }
@@ -117,8 +122,8 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
     /**
      * Exactly one status packet is added to the response.
      */
-    private JSONObject getStatusPacket() throws JSONException {
-        JSONObject packet = new JSONObjectWithLegibleException();
+    private JsonNode getStatusPacket() {
+        ObjectNode packet = jsonMapper.createObjectNode();
         packet.put(APPLICATION_KEY, applicationName);
 
         StateMonitor.Status status = monitor.status();
@@ -127,14 +132,15 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
         return packet;
     }
 
-    private String jsonToString(JSONObject jsonObject) throws JSONException {
-        return jsonObject.toString(4);
+    private static String jsonToString(JsonNode jsonObject) throws JsonProcessingException {
+        return jsonMapper.writerWithDefaultPrettyPrinter()
+                .writeValueAsString(jsonObject);
     }
 
-    private String getAllMetricsPackets() throws JSONException {
+    private String getAllMetricsPackets() throws JsonProcessingException {
         StringBuilder ret = new StringBuilder();
-        List<JSONObject> metricsPackets = getPacketsForSnapshot(getSnapshot(), applicationName, timer.currentTimeMillis());
-        for (JSONObject packet : metricsPackets) {
+        List<JsonNode> metricsPackets = getPacketsForSnapshot(getSnapshot(), applicationName, timer.currentTimeMillis());
+        for (JsonNode packet : metricsPackets) {
             ret.append(PACKET_SEPARATOR); // For legibility and parsing in unit tests
             ret.append(jsonToString(packet));
         }
@@ -150,16 +156,16 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
         }
     }
 
-    private List<JSONObject> getPacketsForSnapshot(MetricSnapshot metricSnapshot, String application, long timestamp) throws JSONException {
+    private List<JsonNode> getPacketsForSnapshot(MetricSnapshot metricSnapshot, String application, long timestamp) {
         if (metricSnapshot == null) return Collections.emptyList();
 
-        List<JSONObject> packets = new ArrayList<>();
+        List<JsonNode> packets = new ArrayList<>();
 
         for (Map.Entry<MetricDimensions, MetricSet> snapshotEntry : metricSnapshot) {
             MetricDimensions metricDimensions = snapshotEntry.getKey();
             MetricSet metricSet = snapshotEntry.getValue();
 
-            JSONObjectWithLegibleException packet = new JSONObjectWithLegibleException();
+            ObjectNode packet = jsonMapper.createObjectNode();
             addMetaData(timestamp, application, packet);
             addDimensions(metricDimensions, packet);
             addMetrics(metricSet, packet);
@@ -168,27 +174,27 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
         return packets;
     }
 
-    private void addMetaData(long timestamp, String application, JSONObjectWithLegibleException packet) {
+    private void addMetaData(long timestamp, String application, ObjectNode packet) {
         packet.put(APPLICATION_KEY, application);
         packet.put(TIMESTAMP_KEY, TimeUnit.MILLISECONDS.toSeconds(timestamp));
     }
 
-    private void addDimensions(MetricDimensions metricDimensions, JSONObjectWithLegibleException packet) throws JSONException {
+    private void addDimensions(MetricDimensions metricDimensions, ObjectNode packet) {
         if (metricDimensions == null) return;
 
         Iterator<Map.Entry<String, String>> dimensionsIterator = metricDimensions.iterator();
         if (dimensionsIterator.hasNext()) {
-            JSONObject jsonDim = new JSONObjectWithLegibleException();
-            packet.put(DIMENSIONS_KEY, jsonDim);
+            ObjectNode jsonDim = jsonMapper.createObjectNode();
+            packet.set(DIMENSIONS_KEY, jsonDim);
             for (Map.Entry<String, String> dimensionEntry : metricDimensions) {
                 jsonDim.put(dimensionEntry.getKey(), dimensionEntry.getValue());
             }
         }
     }
 
-    private void addMetrics(MetricSet metricSet, JSONObjectWithLegibleException packet) throws JSONException {
-        JSONObjectWithLegibleException metrics = new JSONObjectWithLegibleException();
-        packet.put(METRICS_KEY, metrics);
+    private void addMetrics(MetricSet metricSet, ObjectNode packet) {
+        ObjectNode metrics = jsonMapper.createObjectNode();
+        packet.set(METRICS_KEY, metrics);
         for (Map.Entry<String, MetricValue> metric : metricSet) {
             String name = metric.getKey();
             MetricValue value = metric.getValue();
@@ -196,9 +202,9 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
                 metrics.put(name + ".count", ((CountMetric) value).getCount());
             } else if (value instanceof GaugeMetric) {
                 GaugeMetric gauge = (GaugeMetric) value;
-                metrics.put(name + ".average", gauge.getAverage())
-                        .put(name + ".last", gauge.getLast())
-                        .put(name + ".max", gauge.getMax());
+                metrics.put(name + ".average", sanitizeDouble(gauge.getAverage()))
+                        .put(name + ".last", sanitizeDouble(gauge.getLast()))
+                        .put(name + ".max", sanitizeDouble(gauge.getMax()));
                 if (gauge.getPercentiles().isPresent()) {
                     for (Tuple2<String, Double> prefixAndValue : gauge.getPercentiles().get()) {
                         metrics.put(name + "." + prefixAndValue.first + "percentile", prefixAndValue.second.doubleValue());
diff --git a/container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java
index b14dc50edcb..5ac2871d9dd 100644
--- a/container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/StateHandler.java
@@ -1,6 +1,11 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 package com.yahoo.container.jdisc.state;
 
+import com.fasterxml.jackson.core.JsonProcessingException;
+import com.fasterxml.jackson.databind.JsonNode;
+import com.fasterxml.jackson.databind.ObjectMapper;
+import com.fasterxml.jackson.databind.node.ArrayNode;
+import com.fasterxml.jackson.databind.node.ObjectNode;
 import com.google.inject.Inject;
 import com.yahoo.collections.Tuple2;
 import com.yahoo.component.Vtag;
@@ -16,21 +21,18 @@ import com.yahoo.jdisc.handler.ResponseHandler;
 import com.yahoo.jdisc.http.HttpHeaders;
 import com.yahoo.metrics.MetricsPresentationConfig;
 
-import org.json.JSONArray;
-import org.json.JSONException;
-import org.json.JSONObject;
-
+import java.io.ByteArrayOutputStream;
+import java.io.PrintStream;
 import java.net.URI;
 import java.nio.ByteBuffer;
-import java.nio.charset.StandardCharsets;
 import java.util.ArrayList;
 import java.util.Collections;
 import java.util.Iterator;
 import java.util.List;
 import java.util.Map;
 import java.util.concurrent.TimeUnit;
-import java.io.PrintStream;
-import java.io.ByteArrayOutputStream;
+
+import static com.yahoo.container.jdisc.state.JsonUtil.sanitizeDouble;
 
 /**
  * A handler which returns state (health) information from this container instance: Status, metrics and vespa version.
@@ -39,6 +41,8 @@ import java.io.ByteArrayOutputStream;
  */
 public class StateHandler extends AbstractRequestHandler {
 
+    private static final ObjectMapper jsonMapper = new ObjectMapper();
+
     public static final String STATE_API_ROOT = "/state/v1";
     private static final String METRICS_PATH = "metrics";
     private static final String HISTOGRAMS_PATH = "metrics/histograms";
@@ -124,17 +128,16 @@ public class StateHandler extends AbstractRequestHandler {
             }
             base.append(STATE_API_ROOT);
             String uriBase = base.toString();
-            JSONArray linkList = new JSONArray();
+            ArrayNode linkList = jsonMapper.createArrayNode();
             for (String api : new String[] {METRICS_PATH, CONFIG_GENERATION_PATH, HEALTH_PATH, VERSION_PATH}) {
-                JSONObject resource = new JSONObject();
+                ObjectNode resource = jsonMapper.createObjectNode();
                 resource.put("url", uriBase + "/" + api);
-                linkList.put(resource);
+                linkList.add(resource);
             }
-            return new JSONObjectWithLegibleException()
-                    .put("resources", linkList)
-                    .toString(4).getBytes(StandardCharsets.UTF_8);
-        } catch (JSONException e) {
-            throw new RuntimeException("Bad JSON construction.", e);
+            JsonNode resources = jsonMapper.createObjectNode().set("resources", linkList);
+            return toPrettyString(resources);
+        } catch (JsonProcessingException e) {
+            throw new RuntimeException("Bad JSON construction", e);
         }
     }
 
@@ -154,31 +157,31 @@ public class StateHandler extends AbstractRequestHandler {
 
     private static byte[] buildConfigOutput(ApplicationMetadataConfig config) {
         try {
-            return new JSONObjectWithLegibleException()
-                    .put(CONFIG_GENERATION_PATH, new JSONObjectWithLegibleException()
-                            .put("generation", config.generation())
-                            .put("container", new JSONObjectWithLegibleException()
-                                    .put("generation", config.generation())))
-                    .toString(4).getBytes(StandardCharsets.UTF_8);
-        } catch (JSONException e) {
+            return toPrettyString(
+                    jsonMapper.createObjectNode()
+                            .set(CONFIG_GENERATION_PATH, jsonMapper.createObjectNode()
+                                    .put("generation", config.generation())
+                                    .set("container", jsonMapper.createObjectNode()
+                                            .put("generation", config.generation()))));
+        } catch (JsonProcessingException e) {
             throw new RuntimeException("Bad JSON construction.", e);
         }
     }
 
     private static byte[] buildVersionOutput() {
         try {
-            return new JSONObjectWithLegibleException()
-                    .put("version", Vtag.currentVersion)
-                    .toString(4).getBytes(StandardCharsets.UTF_8);
-        } catch (JSONException e) {
+            return toPrettyString(
+                    jsonMapper.createObjectNode()
+                            .put("version", Vtag.currentVersion.toString()));
+        } catch (JsonProcessingException e) {
             throw new RuntimeException("Bad JSON construction.", e);
         }
     }
 
     private byte[] buildMetricOutput(String consumer) {
         try {
-            return buildJsonForConsumer(consumer).toString(4).getBytes(StandardCharsets.UTF_8);
-        } catch (JSONException e) {
+            return toPrettyString(buildJsonForConsumer(consumer));
+        } catch (JsonProcessingException e) {
             throw new RuntimeException("Bad JSON construction.", e);
         }
     }
@@ -191,11 +194,11 @@ public class StateHandler extends AbstractRequestHandler {
         return baos.toByteArray();
     }
 
-    private JSONObjectWithLegibleException buildJsonForConsumer(String consumer) throws JSONException {
-        JSONObjectWithLegibleException ret = new JSONObjectWithLegibleException();
+    private ObjectNode buildJsonForConsumer(String consumer) {
+        ObjectNode ret = jsonMapper.createObjectNode();
         ret.put("time", timer.currentTimeMillis());
-        ret.put("status", new JSONObjectWithLegibleException().put("code", getStatus().name()));
-        ret.put(METRICS_PATH, buildJsonForSnapshot(consumer, getSnapshot()));
+        ret.set("status", jsonMapper.createObjectNode().put("code", getStatus().name()));
+        ret.set(METRICS_PATH, buildJsonForSnapshot(consumer, getSnapshot()));
         return ret;
     }
 
@@ -212,57 +215,62 @@ public class StateHandler extends AbstractRequestHandler {
         return monitor.status();
     }
 
-    private JSONObjectWithLegibleException buildJsonForSnapshot(String consumer, MetricSnapshot metricSnapshot) throws JSONException {
+    private ObjectNode buildJsonForSnapshot(String consumer, MetricSnapshot metricSnapshot) {
         if (metricSnapshot == null) {
-            return new JSONObjectWithLegibleException();
+            return jsonMapper.createObjectNode();
         }
-        JSONObjectWithLegibleException jsonMetric = new JSONObjectWithLegibleException();
-        jsonMetric.put("snapshot", new JSONObjectWithLegibleException()
-                .put("from", metricSnapshot.getFromTime(TimeUnit.MILLISECONDS) / 1000.0)
-                .put("to", metricSnapshot.getToTime(TimeUnit.MILLISECONDS) / 1000.0));
+        ObjectNode jsonMetric = jsonMapper.createObjectNode();
+        jsonMetric.set("snapshot", jsonMapper.createObjectNode()
+                .put("from", sanitizeDouble(metricSnapshot.getFromTime(TimeUnit.MILLISECONDS) / 1000.0))
+                .put("to", sanitizeDouble(metricSnapshot.getToTime(TimeUnit.MILLISECONDS) / 1000.0)));
 
         boolean includeDimensions = !consumer.equals(HEALTH_PATH);
         long periodInMillis = metricSnapshot.getToTime(TimeUnit.MILLISECONDS) -
                               metricSnapshot.getFromTime(TimeUnit.MILLISECONDS);
         for (Tuple tuple : collapseMetrics(metricSnapshot, consumer)) {
-            JSONObjectWithLegibleException jsonTuple = new JSONObjectWithLegibleException();
+            ObjectNode jsonTuple = jsonMapper.createObjectNode();
             jsonTuple.put("name", tuple.key);
             if (tuple.val instanceof CountMetric) {
                 CountMetric count = (CountMetric)tuple.val;
-                jsonTuple.put("values", new JSONObjectWithLegibleException()
+                jsonTuple.set("values", jsonMapper.createObjectNode()
                         .put("count", count.getCount())
-                        .put("rate", (count.getCount() * 1000.0) / periodInMillis));
+                        .put("rate", sanitizeDouble(count.getCount() * 1000.0) / periodInMillis));
             } else if (tuple.val instanceof GaugeMetric) {
                 GaugeMetric gauge = (GaugeMetric) tuple.val;
-                JSONObjectWithLegibleException valueFields = new JSONObjectWithLegibleException();
-                valueFields.put("average", gauge.getAverage())
-                        .put("sum", gauge.getSum())
+                ObjectNode valueFields = jsonMapper.createObjectNode();
+                valueFields.put("average", sanitizeDouble(gauge.getAverage()))
+                        .put("sum", sanitizeDouble(gauge.getSum()))
                         .put("count", gauge.getCount())
-                        .put("last", gauge.getLast())
-                        .put("max", gauge.getMax())
-                        .put("min", gauge.getMin())
-                        .put("rate", (gauge.getCount() * 1000.0) / periodInMillis);
+                        .put("last", sanitizeDouble(gauge.getLast()))
+                        .put("max", sanitizeDouble(gauge.getMax()))
+                        .put("min", sanitizeDouble(gauge.getMin()))
+                        .put("rate", sanitizeDouble((gauge.getCount() * 1000.0) / periodInMillis));
                 if (gauge.getPercentiles().isPresent()) {
                     for (Tuple2<String, Double> prefixAndValue : gauge.getPercentiles().get()) {
-                        valueFields.put(prefixAndValue.first + "percentile", prefixAndValue.second.doubleValue());
+                        valueFields.put(prefixAndValue.first + "percentile", sanitizeDouble(prefixAndValue.second));
                     }
                 }
-                jsonTuple.put("values", valueFields);
+                jsonTuple.set("values", valueFields);
             } else {
                 throw new UnsupportedOperationException(tuple.val.getClass().getName());
             }
             if (tuple.dim != null) {
                 Iterator<Map.Entry<String, String>> it = tuple.dim.iterator();
                 if (it.hasNext() && includeDimensions) {
-                    JSONObjectWithLegibleException jsonDim = new JSONObjectWithLegibleException();
+                    ObjectNode jsonDim = jsonMapper.createObjectNode();
                     while (it.hasNext()) {
                         Map.Entry<String, String> entry = it.next();
                         jsonDim.put(entry.getKey(), entry.getValue());
                     }
-                    jsonTuple.put("dimensions", jsonDim);
+                    jsonTuple.set("dimensions", jsonDim);
                 }
             }
-            jsonMetric.append("values", jsonTuple);
+            ArrayNode values = (ArrayNode) jsonMetric.get("values");
+            if (values == null) {
+                values = jsonMapper.createArrayNode();
+                jsonMetric.set("values", values);
+            }
+            values.add(jsonTuple);
         }
         return jsonMetric;
     }
@@ -316,6 +324,12 @@ public class StateHandler extends AbstractRequestHandler {
         return metrics;
     }
 
+    private static byte[] toPrettyString(JsonNode resources) throws JsonProcessingException {
+        return jsonMapper.writerWithDefaultPrettyPrinter()
+                .writeValueAsString(resources)
+                .getBytes();
+    }
+
     static class Tuple {
 
         final MetricDimensions dim;