Revert "Remove org.json usage [run-systemtest]"

14 files changed, 289 insertions, 218 deletions

diff --git a/container-core/pom.xml b/container-core/pom.xml
index 051b572b28f..7c98b524c73 100644
--- a/container-core/pom.xml
+++ b/container-core/pom.xml
@@ -42,7 +42,6 @@
       <scope>test</scope>
     </dependency>
     <dependency>
-      <!-- TODO Vespa 8: stop providing org.json:json -->
       <groupId>org.json</groupId>
       <artifactId>json</artifactId>
     </dependency>
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 8c902f88e38..92840cee48f 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
@@ -1,14 +1,13 @@
 // 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;
@@ -27,8 +26,6 @@ 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);
     }
@@ -52,14 +49,15 @@ public abstract class HttpHandlerBase extends ThreadedHttpRequestHandler {
     protected JsonResponse resourceListResponse(URI requestUri, List<String> resources) {
         try {
             return new JsonResponse(OK, resourceList(requestUri, resources));
-        } catch (JsonProcessingException e) {
+        } catch (JSONException 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.");
         }
     }
 
-    private static String resourceList(URI requestUri, List<String> resources) throws JsonProcessingException {
+    // TODO: Use jackson with a "Resources" class instead of JSONObject
+    private static String resourceList(URI requestUri, List<String> resources) throws JSONException {
         int port = requestUri.getPort();
         String host = requestUri.getHost();
         StringBuilder base = new StringBuilder("http://");
@@ -68,14 +66,13 @@ public abstract class HttpHandlerBase extends ThreadedHttpRequestHandler {
             base.append(":").append(port);
         }
         String uriBase = base.toString();
-        ArrayNode linkList = jsonMapper.createArrayNode();
+        JSONArray linkList = new JSONArray();
         for (String api : resources) {
-            ObjectNode resource = jsonMapper.createObjectNode();
+            JSONObject resource = new JSONObject();
             resource.put("url", uriBase + api);
-            linkList.add(resource);
+            linkList.put(resource);
         }
-        return jsonMapper.writerWithDefaultPrettyPrinter()
-                .writeValueAsString(jsonMapper.createObjectNode().set("resources", linkList));
+        return new JSONObject().put("resources", linkList).toString(4);
     }
 
 }
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 f1ef7894511..d105eaa9d98 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
@@ -1,16 +1,17 @@
 // 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;
 
 /**
@@ -18,17 +19,19 @@ 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 JsonNode gatherCoredumpMetrics(FileWrapper fileWrapper) {
+    public static JSONObject gatherCoredumpMetrics(FileWrapper fileWrapper) {
         int coredumps = getNumberOfCoredumps(fileWrapper);
-        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");
+        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) {}
         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 28f99096d84..730f7bc13cd 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
@@ -1,9 +1,8 @@
 // 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 org.json.JSONException;
+import org.json.JSONObject;
 
 import java.io.IOException;
 import java.nio.file.Path;
@@ -14,11 +13,9 @@ 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 JsonNode getHostLifePacket(FileWrapper fileWrapper) {
+    public static JSONObject getHostLifePacket(FileWrapper fileWrapper) {
         long upTime;
         int statusCode = 0;
         String statusMessage = "OK";
@@ -32,15 +29,19 @@ public class HostLifeGatherer {
         }
 
 
-        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);
+        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) {}
+
         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
new file mode 100644
index 00000000000..d22dd9d6f4b
--- /dev/null
+++ b/container-core/src/main/java/com/yahoo/container/jdisc/state/JSONObjectWithLegibleException.java
@@ -0,0 +1,87 @@
+// 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/MetricGatherer.java b/container-core/src/main/java/com/yahoo/container/jdisc/state/MetricGatherer.java
index add69403455..6a06a6362f5 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 com.fasterxml.jackson.databind.JsonNode;
+import org.json.JSONObject;
 
 import java.util.ArrayList;
 import java.util.List;
@@ -13,9 +13,9 @@ import java.util.List;
  */
 public class MetricGatherer {
 
-    static List<JsonNode> getAdditionalMetrics() {
+    static List<JSONObject> getAdditionalMetrics() {
         FileWrapper fileWrapper = new FileWrapper();
-        List<JsonNode> packetList = new ArrayList<>();
+        List<JSONObject> 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 e8d829eafb1..3d3f0e4b677 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
@@ -1,11 +1,6 @@
 // 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;
@@ -18,6 +13,9 @@ 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;
@@ -46,8 +44,6 @@ 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";
@@ -101,19 +97,19 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
             }
             String output = jsonToString(getStatusPacket()) + getAllMetricsPackets() + "\n";
             return output.getBytes(StandardCharsets.UTF_8);
-        } catch (JsonProcessingException e) {
+        } catch (JSONException e) {
             throw new RuntimeException("Bad JSON construction.", e);
         }
     }
 
-    private byte[] getMetricsArray() throws JsonProcessingException {
-        ObjectNode root = jsonMapper.createObjectNode();
-        ArrayNode jsonArray = jsonMapper.createArrayNode();
-        jsonArray.add(getStatusPacket());
+    private byte[] getMetricsArray() throws JSONException {
+        JSONObject root = new JSONObject();
+        JSONArray jsonArray = new JSONArray();
+        jsonArray.put(getStatusPacket());
         getPacketsForSnapshot(getSnapshot(), applicationName, timer.currentTimeMillis())
-                .forEach(jsonArray::add);
-        MetricGatherer.getAdditionalMetrics().forEach(jsonArray::add);
-        root.set("metrics", jsonArray);
+                .forEach(jsonArray::put);
+        MetricGatherer.getAdditionalMetrics().forEach(jsonArray::put);
+        root.put("metrics", jsonArray);
         return jsonToString(root)
                 .getBytes(StandardCharsets.UTF_8);
     }
@@ -121,8 +117,8 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
     /**
      * Exactly one status packet is added to the response.
      */
-    private JsonNode getStatusPacket() {
-        ObjectNode packet = jsonMapper.createObjectNode();
+    private JSONObject getStatusPacket() throws JSONException {
+        JSONObject packet = new JSONObjectWithLegibleException();
         packet.put(APPLICATION_KEY, applicationName);
 
         StateMonitor.Status status = monitor.status();
@@ -131,15 +127,14 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
         return packet;
     }
 
-    private static String jsonToString(JsonNode jsonObject) throws JsonProcessingException {
-        return jsonMapper.writerWithDefaultPrettyPrinter()
-                .writeValueAsString(jsonObject);
+    private String jsonToString(JSONObject jsonObject) throws JSONException {
+        return jsonObject.toString(4);
     }
 
-    private String getAllMetricsPackets() throws JsonProcessingException {
+    private String getAllMetricsPackets() throws JSONException {
         StringBuilder ret = new StringBuilder();
-        List<JsonNode> metricsPackets = getPacketsForSnapshot(getSnapshot(), applicationName, timer.currentTimeMillis());
-        for (JsonNode packet : metricsPackets) {
+        List<JSONObject> metricsPackets = getPacketsForSnapshot(getSnapshot(), applicationName, timer.currentTimeMillis());
+        for (JSONObject packet : metricsPackets) {
             ret.append(PACKET_SEPARATOR); // For legibility and parsing in unit tests
             ret.append(jsonToString(packet));
         }
@@ -155,16 +150,16 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
         }
     }
 
-    private List<JsonNode> getPacketsForSnapshot(MetricSnapshot metricSnapshot, String application, long timestamp) {
+    private List<JSONObject> getPacketsForSnapshot(MetricSnapshot metricSnapshot, String application, long timestamp) throws JSONException {
         if (metricSnapshot == null) return Collections.emptyList();
 
-        List<JsonNode> packets = new ArrayList<>();
+        List<JSONObject> packets = new ArrayList<>();
 
         for (Map.Entry<MetricDimensions, MetricSet> snapshotEntry : metricSnapshot) {
             MetricDimensions metricDimensions = snapshotEntry.getKey();
             MetricSet metricSet = snapshotEntry.getValue();
 
-            ObjectNode packet = jsonMapper.createObjectNode();
+            JSONObjectWithLegibleException packet = new JSONObjectWithLegibleException();
             addMetaData(timestamp, application, packet);
             addDimensions(metricDimensions, packet);
             addMetrics(metricSet, packet);
@@ -173,27 +168,27 @@ public class MetricsPacketsHandler extends AbstractRequestHandler {
         return packets;
     }
 
-    private void addMetaData(long timestamp, String application, ObjectNode packet) {
+    private void addMetaData(long timestamp, String application, JSONObjectWithLegibleException packet) {
         packet.put(APPLICATION_KEY, application);
         packet.put(TIMESTAMP_KEY, TimeUnit.MILLISECONDS.toSeconds(timestamp));
     }
 
-    private void addDimensions(MetricDimensions metricDimensions, ObjectNode packet) {
+    private void addDimensions(MetricDimensions metricDimensions, JSONObjectWithLegibleException packet) throws JSONException {
         if (metricDimensions == null) return;
 
         Iterator<Map.Entry<String, String>> dimensionsIterator = metricDimensions.iterator();
         if (dimensionsIterator.hasNext()) {
-            ObjectNode jsonDim = jsonMapper.createObjectNode();
-            packet.set(DIMENSIONS_KEY, jsonDim);
+            JSONObject jsonDim = new JSONObjectWithLegibleException();
+            packet.put(DIMENSIONS_KEY, jsonDim);
             for (Map.Entry<String, String> dimensionEntry : metricDimensions) {
                 jsonDim.put(dimensionEntry.getKey(), dimensionEntry.getValue());
             }
         }
     }
 
-    private void addMetrics(MetricSet metricSet, ObjectNode packet) {
-        ObjectNode metrics = jsonMapper.createObjectNode();
-        packet.set(METRICS_KEY, metrics);
+    private void addMetrics(MetricSet metricSet, JSONObjectWithLegibleException packet) throws JSONException {
+        JSONObjectWithLegibleException metrics = new JSONObjectWithLegibleException();
+        packet.put(METRICS_KEY, metrics);
         for (Map.Entry<String, MetricValue> metric : metricSet) {
             String name = metric.getKey();
             MetricValue value = metric.getValue();
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 1eb34e15258..b14dc50edcb 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
@@ -1,11 +1,6 @@
 // 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;
@@ -21,16 +16,21 @@ import com.yahoo.jdisc.handler.ResponseHandler;
 import com.yahoo.jdisc.http.HttpHeaders;
 import com.yahoo.metrics.MetricsPresentationConfig;
 
-import java.io.ByteArrayOutputStream;
-import java.io.PrintStream;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
+
 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;
 
 /**
  * A handler which returns state (health) information from this container instance: Status, metrics and vespa version.
@@ -39,8 +39,6 @@ import java.util.concurrent.TimeUnit;
  */
 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";
@@ -126,16 +124,17 @@ public class StateHandler extends AbstractRequestHandler {
             }
             base.append(STATE_API_ROOT);
             String uriBase = base.toString();
-            ArrayNode linkList = jsonMapper.createArrayNode();
+            JSONArray linkList = new JSONArray();
             for (String api : new String[] {METRICS_PATH, CONFIG_GENERATION_PATH, HEALTH_PATH, VERSION_PATH}) {
-                ObjectNode resource = jsonMapper.createObjectNode();
+                JSONObject resource = new JSONObject();
                 resource.put("url", uriBase + "/" + api);
-                linkList.add(resource);
+                linkList.put(resource);
             }
-            JsonNode resources = jsonMapper.createObjectNode().set("resources", linkList);
-            return toPrettyString(resources);
-        } catch (JsonProcessingException e) {
-            throw new RuntimeException("Bad JSON construction", e);
+            return new JSONObjectWithLegibleException()
+                    .put("resources", linkList)
+                    .toString(4).getBytes(StandardCharsets.UTF_8);
+        } catch (JSONException e) {
+            throw new RuntimeException("Bad JSON construction.", e);
         }
     }
 
@@ -155,31 +154,31 @@ public class StateHandler extends AbstractRequestHandler {
 
     private static byte[] buildConfigOutput(ApplicationMetadataConfig config) {
         try {
-            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) {
+            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) {
             throw new RuntimeException("Bad JSON construction.", e);
         }
     }
 
     private static byte[] buildVersionOutput() {
         try {
-            return toPrettyString(
-                    jsonMapper.createObjectNode()
-                            .put("version", Vtag.currentVersion.toString()));
-        } catch (JsonProcessingException e) {
+            return new JSONObjectWithLegibleException()
+                    .put("version", Vtag.currentVersion)
+                    .toString(4).getBytes(StandardCharsets.UTF_8);
+        } catch (JSONException e) {
             throw new RuntimeException("Bad JSON construction.", e);
         }
     }
 
     private byte[] buildMetricOutput(String consumer) {
         try {
-            return toPrettyString(buildJsonForConsumer(consumer));
-        } catch (JsonProcessingException e) {
+            return buildJsonForConsumer(consumer).toString(4).getBytes(StandardCharsets.UTF_8);
+        } catch (JSONException e) {
             throw new RuntimeException("Bad JSON construction.", e);
         }
     }
@@ -192,11 +191,11 @@ public class StateHandler extends AbstractRequestHandler {
         return baos.toByteArray();
     }
 
-    private ObjectNode buildJsonForConsumer(String consumer) {
-        ObjectNode ret = jsonMapper.createObjectNode();
+    private JSONObjectWithLegibleException buildJsonForConsumer(String consumer) throws JSONException {
+        JSONObjectWithLegibleException ret = new JSONObjectWithLegibleException();
         ret.put("time", timer.currentTimeMillis());
-        ret.set("status", jsonMapper.createObjectNode().put("code", getStatus().name()));
-        ret.set(METRICS_PATH, buildJsonForSnapshot(consumer, getSnapshot()));
+        ret.put("status", new JSONObjectWithLegibleException().put("code", getStatus().name()));
+        ret.put(METRICS_PATH, buildJsonForSnapshot(consumer, getSnapshot()));
         return ret;
     }
 
@@ -213,12 +212,12 @@ public class StateHandler extends AbstractRequestHandler {
         return monitor.status();
     }
 
-    private ObjectNode buildJsonForSnapshot(String consumer, MetricSnapshot metricSnapshot) {
+    private JSONObjectWithLegibleException buildJsonForSnapshot(String consumer, MetricSnapshot metricSnapshot) throws JSONException {
         if (metricSnapshot == null) {
-            return jsonMapper.createObjectNode();
+            return new JSONObjectWithLegibleException();
         }
-        ObjectNode jsonMetric = jsonMapper.createObjectNode();
-        jsonMetric.set("snapshot", 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));
 
@@ -226,16 +225,16 @@ public class StateHandler extends AbstractRequestHandler {
         long periodInMillis = metricSnapshot.getToTime(TimeUnit.MILLISECONDS) -
                               metricSnapshot.getFromTime(TimeUnit.MILLISECONDS);
         for (Tuple tuple : collapseMetrics(metricSnapshot, consumer)) {
-            ObjectNode jsonTuple = jsonMapper.createObjectNode();
+            JSONObjectWithLegibleException jsonTuple = new JSONObjectWithLegibleException();
             jsonTuple.put("name", tuple.key);
             if (tuple.val instanceof CountMetric) {
                 CountMetric count = (CountMetric)tuple.val;
-                jsonTuple.set("values", jsonMapper.createObjectNode()
+                jsonTuple.put("values", new JSONObjectWithLegibleException()
                         .put("count", count.getCount())
                         .put("rate", (count.getCount() * 1000.0) / periodInMillis));
             } else if (tuple.val instanceof GaugeMetric) {
                 GaugeMetric gauge = (GaugeMetric) tuple.val;
-                ObjectNode valueFields = jsonMapper.createObjectNode();
+                JSONObjectWithLegibleException valueFields = new JSONObjectWithLegibleException();
                 valueFields.put("average", gauge.getAverage())
                         .put("sum", gauge.getSum())
                         .put("count", gauge.getCount())
@@ -248,27 +247,22 @@ public class StateHandler extends AbstractRequestHandler {
                         valueFields.put(prefixAndValue.first + "percentile", prefixAndValue.second.doubleValue());
                     }
                 }
-                jsonTuple.set("values", valueFields);
+                jsonTuple.put("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) {
-                    ObjectNode jsonDim = jsonMapper.createObjectNode();
+                    JSONObjectWithLegibleException jsonDim = new JSONObjectWithLegibleException();
                     while (it.hasNext()) {
                         Map.Entry<String, String> entry = it.next();
                         jsonDim.put(entry.getKey(), entry.getValue());
                     }
-                    jsonTuple.set("dimensions", jsonDim);
+                    jsonTuple.put("dimensions", jsonDim);
                 }
             }
-            ArrayNode values = (ArrayNode) jsonMetric.get("values");
-            if (values == null) {
-                values = jsonMapper.createArrayNode();
-                jsonMetric.set("values", values);
-            }
-            values.add(jsonTuple);
+            jsonMetric.append("values", jsonTuple);
         }
         return jsonMetric;
     }
@@ -322,12 +316,6 @@ 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;
diff --git a/container-core/src/main/java/org/json/package-info.java b/container-core/src/main/java/org/json/package-info.java
index 7ca9fe91e31..44630ad235a 100644
--- a/container-core/src/main/java/org/json/package-info.java
+++ b/container-core/src/main/java/org/json/package-info.java
@@ -1,5 +1,5 @@
 // Copyright 2017 Yahoo Holdings. Licensed under the terms of the Apache 2.0 license. See LICENSE in the project root.
 @ExportPackage
 package org.json;
-// TODO Vespa 8: stop providing org.json
+
 import com.yahoo.osgi.annotation.ExportPackage;
diff --git a/container-core/src/test/java/com/yahoo/container/handler/metrics/MetricsV2HandlerTest.java b/container-core/src/test/java/com/yahoo/container/handler/metrics/MetricsV2HandlerTest.java
index ca4bec30322..9020ed91026 100644
--- a/container-core/src/test/java/com/yahoo/container/handler/metrics/MetricsV2HandlerTest.java
+++ b/container-core/src/test/java/com/yahoo/container/handler/metrics/MetricsV2HandlerTest.java
@@ -1,18 +1,17 @@
 // Copyright 2019 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.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;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
 import org.junit.Before;
 import org.junit.Ignore;
 import org.junit.Rule;
 import org.junit.Test;
 
 import java.io.BufferedReader;
-import java.io.IOException;
 import java.io.InputStream;
 import java.io.InputStreamReader;
 import java.util.concurrent.Executors;
@@ -35,8 +34,6 @@ import static org.junit.Assert.fail;
  */
 public class MetricsV2HandlerTest {
 
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
-
     private static final String URI_BASE = "http://localhost";
 
     private static final String V2_URI = URI_BASE + V2_PATH;
@@ -82,29 +79,29 @@ public class MetricsV2HandlerTest {
     @Test
     public void v2_response_contains_values_uri() throws Exception {
         String response = testDriver.sendRequest(V2_URI).readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JSONObject root = new JSONObject(response);
         assertTrue(root.has("resources"));
 
-        ArrayNode resources = (ArrayNode) root.get("resources");
-        assertEquals(1, resources.size());
+        JSONArray resources = root.getJSONArray("resources");
+        assertEquals(1, resources.length());
 
-        JsonNode valuesUri = resources.get(0);
-        assertEquals(VALUES_URI, valuesUri.get("url").textValue());
+        JSONObject valuesUri = resources.getJSONObject(0);
+        assertEquals(VALUES_URI, valuesUri.getString("url"));
     }
 
     @Ignore
     @Test
-    public void visually_inspect_values_response() {
-        JsonNode responseJson = getResponseAsJson(null);
-        System.out.println(responseJson);
+    public void visually_inspect_values_response() throws Exception {
+        JSONObject responseJson = getResponseAsJson(null);
+        System.out.println(responseJson.toString(4));
     }
 
     @Test
     public void invalid_path_yields_error_response() throws Exception {
         String response = testDriver.sendRequest(V2_URI + "/invalid").readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JSONObject root = new JSONObject(response);
         assertTrue(root.has("error"));
-        assertTrue(root.get("error" ).textValue().startsWith("No content"));
+        assertTrue(root.getString("error" ).startsWith("No content"));
     }
 
     @Test
@@ -114,23 +111,23 @@ public class MetricsV2HandlerTest {
     }
 
     @Test
-    public void consumer_is_propagated_to_metrics_proxy_api() {
-        JsonNode responseJson = getResponseAsJson(CUSTOM_CONSUMER);
+    public void consumer_is_propagated_to_metrics_proxy_api() throws JSONException {
+        JSONObject responseJson = getResponseAsJson(CUSTOM_CONSUMER);
 
-        JsonNode firstNodeMetricsValues =
-                responseJson.get("nodes").get(0)
-                        .get("node")
-                        .get("metrics").get(0)
-                        .get("values");
+        JSONObject firstNodeMetricsValues =
+                responseJson.getJSONArray("nodes").getJSONObject(0)
+                        .getJSONObject("node")
+                        .getJSONArray("metrics").getJSONObject(0)
+                        .getJSONObject("values");
 
         assertTrue(firstNodeMetricsValues.has(REPLACED_CPU_METRIC));
     }
 
-    private JsonNode getResponseAsJson(String consumer) {
+    private JSONObject getResponseAsJson(String consumer) {
         String response = testDriver.sendRequest(VALUES_URI + consumerQuery(consumer)).readAll();
         try {
-            return jsonMapper.readTree(response);
-        } catch (IOException e) {
+            return new JSONObject(response);
+        } catch (JSONException e) {
             fail("Failed to create json object: " + e.getMessage());
             throw new RuntimeException(e);
         }
diff --git a/container-core/src/test/java/com/yahoo/container/handler/metrics/PrometheusV1HandlerTest.java b/container-core/src/test/java/com/yahoo/container/handler/metrics/PrometheusV1HandlerTest.java
index 9ffce6d1c28..a0e8c131c2b 100644
--- a/container-core/src/test/java/com/yahoo/container/handler/metrics/PrometheusV1HandlerTest.java
+++ b/container-core/src/test/java/com/yahoo/container/handler/metrics/PrometheusV1HandlerTest.java
@@ -1,11 +1,15 @@
 // Copyright 2019 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.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;
+import java.io.BufferedReader;
+import java.io.InputStream;
+import java.io.InputStreamReader;
+import java.util.stream.Collectors;
+import org.json.JSONArray;
+import org.json.JSONException;
+import org.json.JSONObject;
 import org.junit.Before;
 import org.junit.Ignore;
 import org.junit.Rule;
@@ -22,14 +26,13 @@ import static com.yahoo.container.handler.metrics.MetricsV2Handler.consumerQuery
 import static com.yahoo.container.handler.metrics.MetricsV2HandlerTest.getFileContents;
 import static org.junit.Assert.assertEquals;
 import static org.junit.Assert.assertTrue;
+import static org.junit.Assert.fail;
 
 /**
  * @author gjoranv
  */
 public class PrometheusV1HandlerTest {
 
-    private static final ObjectMapper jsonMapper = new ObjectMapper();
-
     private static final String URI_BASE = "http://localhost";
 
     private static final String V1_URI = URI_BASE + PrometheusV1Handler.V1_PATH;
@@ -76,14 +79,14 @@ public class PrometheusV1HandlerTest {
     @Test
     public void v1_response_contains_values_uri() throws Exception {
         String response = testDriver.sendRequest(V1_URI).readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JSONObject root = new JSONObject(response);
         assertTrue(root.has("resources"));
 
-        ArrayNode resources = (ArrayNode) root.get("resources");
-        assertEquals(1, resources.size());
+        JSONArray resources = root.getJSONArray("resources");
+        assertEquals(1, resources.length());
 
-        JsonNode valuesUri = resources.get(0);
-        assertEquals(VALUES_URI, valuesUri.get("url").asText());
+        JSONObject valuesUri = resources.getJSONObject(0);
+        assertEquals(VALUES_URI, valuesUri.getString("url"));
     }
 
     @Ignore
@@ -96,9 +99,9 @@ public class PrometheusV1HandlerTest {
     @Test
     public void invalid_path_yields_error_response() throws Exception {
         String response = testDriver.sendRequest(V1_URI + "/invalid").readAll();
-        JsonNode root = jsonMapper.readTree(response);
+        JSONObject root = new JSONObject(response);
         assertTrue(root.has("error"));
-        assertTrue(root.get("error" ).textValue().startsWith("No content"));
+        assertTrue(root.getString("error" ).startsWith("No content"));
     }
 
     @Test
diff --git a/container-core/src/test/java/com/yahoo/container/jdisc/state/CoredumpGathererTest.java b/container-core/src/test/java/com/yahoo/container/jdisc/state/CoredumpGathererTest.java
index 8a3d0e837c5..c1f7d790fa5 100644
--- a/container-core/src/test/java/com/yahoo/container/jdisc/state/CoredumpGathererTest.java
+++ b/container-core/src/test/java/com/yahoo/container/jdisc/state/CoredumpGathererTest.java
@@ -1,7 +1,8 @@
 // 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 org.json.JSONException;
+import org.json.JSONObject;
 import org.junit.Test;
 
 import java.nio.file.Path;
@@ -16,12 +17,12 @@ import static org.junit.Assert.assertEquals;
 public class CoredumpGathererTest {
 
     @Test
-    public void finds_one_coredump()  {
-    JsonNode packet = CoredumpGatherer.gatherCoredumpMetrics(new MockFileWrapper());
+    public void finds_one_coredump() throws JSONException {
+    JSONObject packet = CoredumpGatherer.gatherCoredumpMetrics(new MockFileWrapper());
 
-    assertEquals("system-coredumps-processing", packet.get("application").textValue());
-    assertEquals(1, packet.get("status_code").intValue());
-    assertEquals("Found 1 coredump(s)", packet.get("status_msg").textValue());
+    assertEquals("system-coredumps-processing", packet.getString("application"));
+    assertEquals(1, packet.getInt("status_code"));
+    assertEquals("Found 1 coredump(s)", packet.getString("status_msg"));
 
     }
 
diff --git a/container-core/src/test/java/com/yahoo/container/jdisc/state/HostLifeGathererTest.java b/container-core/src/test/java/com/yahoo/container/jdisc/state/HostLifeGathererTest.java
index 12852c9d54c..d025b9662d2 100644
--- a/container-core/src/test/java/com/yahoo/container/jdisc/state/HostLifeGathererTest.java
+++ b/container-core/src/test/java/com/yahoo/container/jdisc/state/HostLifeGathererTest.java
@@ -1,7 +1,8 @@
 // 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 org.json.JSONException;
+import org.json.JSONObject;
 import org.junit.Test;
 
 import java.nio.file.Path;
@@ -15,15 +16,15 @@ import static org.junit.Assert.assertEquals;
 public class HostLifeGathererTest {
 
     @Test
-    public void host_is_alive() {
-        JsonNode packet = HostLifeGatherer.getHostLifePacket(new MockFileWrapper());
-        JsonNode metrics = packet.get("metrics");
-        assertEquals("host_life", packet.get("application").textValue());
-        assertEquals(0, packet.get("status_code").intValue());
-        assertEquals("OK", packet.get("status_msg").textValue());
-
-        assertEquals(123L, metrics.get("uptime").longValue());
-        assertEquals(1, metrics.get("alive").intValue());
+    public void host_is_alive() throws JSONException {
+        JSONObject packet = HostLifeGatherer.getHostLifePacket(new MockFileWrapper());
+        JSONObject metrics = packet.getJSONObject("metrics");
+        assertEquals("host_life", packet.getString("application"));
+        assertEquals(0, packet.getInt("status_code"));
+        assertEquals("OK", packet.getString("status_msg"));
+
+        assertEquals(123l, metrics.getLong("uptime"));
+        assertEquals(1, metrics.getInt("alive"));
 
     }
 
diff --git a/container-core/src/test/java/com/yahoo/container/jdisc/state/StateHandlerTest.java b/container-core/src/test/java/com/yahoo/container/jdisc/state/StateHandlerTest.java
index 385eb627427..1258ecdc46f 100644
--- a/container-core/src/test/java/com/yahoo/container/jdisc/state/StateHandlerTest.java
+++ b/container-core/src/test/java/com/yahoo/container/jdisc/state/StateHandlerTest.java
@@ -98,38 +98,37 @@ public class StateHandlerTest extends StateHandlerTestBase {
         snapshotProvider.setSnapshot(snapshot);
         advanceToNextSnapshot();
         assertEquals("{\n" +
-                        "  \"time\" : 300000,\n" +
-                        "  \"status\" : {\n" +
-                        "    \"code\" : \"up\"\n" +
-                        "  },\n" +
-                        "  \"metrics\" : {\n" +
-                        "    \"snapshot\" : {\n" +
-                        "      \"from\" : 0.0,\n" +
-                        "      \"to\" : 300.0\n" +
-                        "    },\n" +
-                        "    \"values\" : [ {\n" +
-                        "      \"name\" : \"foo\",\n" +
-                        "      \"values\" : {\n" +
-                        "        \"count\" : 1,\n" +
-                        "        \"rate\" : 0.0033333333333333335\n" +
-                        "      }\n" +
-                        "    }, {\n" +
-                        "      \"name\" : \"bar\",\n" +
-                        "      \"values\" : {\n" +
-                        "        \"average\" : 3.5,\n" +
-                        "        \"sum\" : 14.0,\n" +
-                        "        \"count\" : 4,\n" +
-                        "        \"last\" : 5.0,\n" +
-                        "        \"max\" : 5.0,\n" +
-                        "        \"min\" : 2.0,\n" +
-                        "        \"rate\" : 0.013333333333333334\n" +
-                        "      },\n" +
-                        "      \"dimensions\" : {\n" +
-                        "        \"component\" : \"test\"\n" +
-                        "      }\n" +
-                        "    } ]\n" +
-                        "  }\n" +
-                        "}",
+                     "    \"metrics\": {\n" +
+                     "        \"snapshot\": {\n" +
+                     "            \"from\": 0,\n" +
+                     "            \"to\": 300\n" +
+                     "        },\n" +
+                     "        \"values\": [\n" +
+                     "            {\n" +
+                     "                \"name\": \"foo\",\n" +
+                     "                \"values\": {\n" +
+                     "                    \"count\": 1,\n" +
+                     "                    \"rate\": 0.0033333333333333335\n" +
+                     "                }\n" +
+                     "            },\n" +
+                     "            {\n" +
+                     "                \"dimensions\": {\"component\": \"test\"},\n" +
+                     "                \"name\": \"bar\",\n" +
+                     "                \"values\": {\n" +
+                     "                    \"average\": 3.5,\n" +
+                     "                    \"count\": 4,\n" +
+                     "                    \"last\": 5,\n" +
+                     "                    \"max\": 5,\n" +
+                     "                    \"min\": 2,\n" +
+                     "                    \"rate\": 0.013333333333333334,\n" +
+                     "                    \"sum\": 14\n" +
+                     "                }\n" +
+                     "            }\n" +
+                     "        ]\n" +
+                     "    },\n" +
+                     "    \"status\": {\"code\": \"up\"},\n" +
+                     "    \"time\": 300000\n" +
+                     "}",
                      requestAsString(V1_URI + "all"));
     }