TagMap that can "mostly" be toggled on / off

Changes TagMap to be an interface with two distinct implementations:
- One that extends HashMap
- One that implements the new map structure

Next change will make it possible to switch between the map implementations via configuration

To try and make both TagMap implementations reasonably efficient, added a more method variations:
- set methods now return void to avoid Entry creation for HashMap implementation
- getAndSet - replaces set for the add cases where the previous Entry is needed

- remove(String) - now returns a boolean to indicate that a change happened rather than returning the value or entry
- getAndRemove - returns an Entry

Many TagMapTest and TagMapLedgerTest have been parameterized to test both implementations of TagMaps

Updated calling code & other tests as needed

Author: dougqh

dd-java-agent/agent-bootstrap/src/main/java/datadog/trace/bootstrap/instrumentation/decorator/HttpServerDecorator.java

@@ -13,6 +13,7 @@
 import datadog.trace.api.Config;
 import datadog.trace.api.DDTags;
 import datadog.trace.api.DDTraceId;
+import datadog.trace.api.TagMap;
 import datadog.trace.api.TraceConfig;
 import datadog.trace.api.function.TriConsumer;
 import datadog.trace.api.function.TriFunction;
@@ -408,7 +409,7 @@ public String getSpanType() {
     }
 
     @Override
-    public Map<String, Object> getTags() {
+    public TagMap getTags() {
       return serverSpan.getTags();
     }
 

dd-java-agent/agent-debugger/src/test/java/com/datadog/debugger/exception/DefaultExceptionDebuggerTest.java

@@ -57,7 +57,7 @@ public class DefaultExceptionDebuggerTest {
   private ConfigurationUpdater configurationUpdater;
   private DefaultExceptionDebugger exceptionDebugger;
   private TestSnapshotListener listener;
-  private TagMap spanTags = new TagMap();
+  private TagMap spanTags = TagMap.create();
 
   @BeforeEach
   public void setUp() {

dd-java-agent/appsec/src/test/groovy/com/datadog/appsec/gateway/GatewayBridgeSpecification.groovy

@@ -989,7 +989,7 @@ class GatewayBridgeSpecification extends DDSpecification {
       getTraceSegment() >> traceSegment
     }
     final spanInfo = Mock(AgentSpan) {
-      getTags() >> ['http.route':'/']
+      getTags() >> TagMap.fromMap(['http.route':'/'])
     }
 
     when:

dd-trace-core/src/main/java/datadog/trace/core/CoreTracer.java

@@ -1888,7 +1888,7 @@ protected ConfigSnapshot(
    */
   static TagMap withTracerTags(
       Map<String, ?> userSpanTags, Config config, TraceConfig traceConfig) {
-    final TagMap result = new TagMap();
+    final TagMap result = TagMap.create();
     result.putAll(userSpanTags);
     if (null != config) { // static
       if (!config.getEnv().isEmpty()) {

dd-trace-core/src/main/java/datadog/trace/core/DDSpanContext.java

@@ -342,7 +342,10 @@ public DDSpanContext(
     assert pathwayContext != null;
     this.pathwayContext = pathwayContext;
 
-    this.unsafeTags = new TagMap();
+    // The +1 is the magic number from the tags below that we set at the end,
+    // and "* 4 / 3" is to make sure that we don't resize immediately
+    final int capacity = Math.max((tagsSize <= 0 ? 3 : (tagsSize + 1)) * 4 / 3, 8);
+    this.unsafeTags = TagMap.create(capacity);
 
     // must set this before setting the service and resource names below
     this.profilingContextIntegration = profilingContextIntegration;
@@ -772,7 +775,7 @@ void setAllTags(final TagMap map, boolean needsIntercept) {
               Object value = tagEntry.objectValue();
 
               if (!tagInterceptor.interceptTag(ctx, tag, value)) {
-                ctx.unsafeTags.putEntry(tagEntry);
+                ctx.unsafeTags.set(tagEntry);
               }
             });
       } else {
@@ -790,15 +793,15 @@ void setAllTags(final TagMap.Ledger ledger) {
     synchronized (unsafeTags) {
       for (final TagMap.EntryChange entryChange : ledger) {
         if (entryChange.isRemoval()) {
-          unsafeTags.removeEntry(entryChange.tag());
+          unsafeTags.remove(entryChange.tag());
         } else {
           TagMap.Entry entry = (TagMap.Entry) entryChange;
 
           String tag = entry.tag();
           Object value = entry.objectValue();
 
           if (!tagInterceptor.interceptTag(this, tag, value)) {
-            unsafeTags.putEntry(entry);
+            unsafeTags.set(entry);
           }
         }
       }

dd-trace-core/src/main/java/datadog/trace/core/tagprocessor/IntegrationAdder.java

@@ -2,22 +2,20 @@
 
 import static datadog.trace.api.DDTags.DD_INTEGRATION;
 
+import datadog.trace.api.TagMap;
 import datadog.trace.bootstrap.instrumentation.api.AgentSpanLink;
 import datadog.trace.core.DDSpanContext;
 import java.util.List;
-import java.util.Map;
-
-public class IntegrationAdder implements TagsPostProcessor {
 
+public class IntegrationAdder extends TagsPostProcessor {
   @Override
-  public Map<String, Object> processTags(
-      Map<String, Object> unsafeTags, DDSpanContext spanContext, List<AgentSpanLink> spanLinks) {
+  public void processTags(
+      TagMap unsafeTags, DDSpanContext spanContext, List<AgentSpanLink> spanLinks) {
     final CharSequence instrumentationName = spanContext.getIntegrationName();
     if (instrumentationName != null) {
-      unsafeTags.put(DD_INTEGRATION, instrumentationName);
+      unsafeTags.set(DD_INTEGRATION, instrumentationName);
     } else {
       unsafeTags.remove(DD_INTEGRATION);
     }
-    return unsafeTags;
   }
 }

dd-trace-core/src/main/java/datadog/trace/core/tagprocessor/PayloadTagsProcessor.java

@@ -79,7 +79,7 @@ public void processTags(
       RedactionRules redactionRules = tagPrefixRedactionRules.getValue();
       Object tagValue = unsafeTags.getObject(tagPrefix);
       if (tagValue instanceof PayloadTagsData) {
-        if (unsafeTags.remove(tagPrefix) != null) {
+        if (unsafeTags.remove(tagPrefix)) {
           spanMaxTags -= 1;
         }
 

dd-trace-core/src/test/groovy/datadog/trace/core/datastreams/DefaultPathwayContextTest.groovy

@@ -3,6 +3,7 @@ package datadog.trace.core.datastreams
 import datadog.communication.ddagent.DDAgentFeaturesDiscovery
 import datadog.trace.api.Config
 import datadog.trace.api.DDTraceId
+import datadog.trace.api.TagMap
 import datadog.trace.api.TraceConfig
 import datadog.trace.api.WellKnownTags
 import datadog.trace.api.datastreams.StatsPoint
@@ -454,7 +455,7 @@ class DefaultPathwayContextTest extends DDCoreSpecification {
     Map<String, String> carrier = [(PROPAGATION_KEY_BASE64): encoded, "someotherkey": "someothervalue"]
     def contextVisitor = new Base64MapContextVisitor()
 
-    def spanContext = new ExtractedContext(DDTraceId.ONE, 1, 0, null, 0, null, null, null, null, localTraceConfig, DATADOG)
+    def spanContext = new ExtractedContext(DDTraceId.ONE, 1, 0, null, 0, null, (TagMap)null, null, null, localTraceConfig, DATADOG)
     def baseContext = AgentSpan.fromSpanContext(spanContext).storeInto(root())
     def propagator = dataStreams.propagator()
 
@@ -549,7 +550,7 @@ class DefaultPathwayContextTest extends DDCoreSpecification {
     def encoded = context.encode()
     Map<String, String> carrier = [(PROPAGATION_KEY_BASE64): encoded, "someotherkey": "someothervalue"]
     def contextVisitor = new Base64MapContextVisitor()
-    def spanContext = new ExtractedContext(DDTraceId.ONE, 1, 0, null, 0, null, null, null, null, null, DATADOG)
+    def spanContext = new ExtractedContext(DDTraceId.ONE, 1, 0, null, 0, null, (TagMap)null, null, null, null, DATADOG)
     def baseContext = AgentSpan.fromSpanContext(spanContext).storeInto(root())
     def propagator = dataStreams.propagator()
 

internal-api/src/main/java/datadog/trace/api/Config.java

@@ -3657,9 +3657,7 @@ public boolean isJdkSocketEnabled() {
   public TagMap getLocalRootSpanTags() {
     final Map<String, String> runtimeTags = getRuntimeTags();
 
-    final TagMap result = new TagMap();
-    result.putAll(runtimeTags);
-
+    final TagMap result = TagMap.fromMap(runtimeTags);
     result.put(LANGUAGE_TAG_KEY, LANGUAGE_TAG_VALUE);
     result.put(SCHEMA_VERSION_TAG_KEY, SpanNaming.instance().version());
     result.put(DDTags.PROFILING_ENABLED, isProfilingEnabled() ? 1 : 0);