PR 6524 with amendments

api/incubator/src/main/java/io/opentelemetry/api/incubator/propagation/CaseInsensitiveMap.java

@@ -8,24 +8,38 @@
 import java.util.HashMap;
 import java.util.Locale;
 import java.util.Map;
+import javax.annotation.Nonnull;
 import javax.annotation.Nullable;
 
 class CaseInsensitiveMap extends HashMap<String, String> {
 
  private static final long serialVersionUID = -4202518750189126871L;
 
+ CaseInsensitiveMap() {}
+
  CaseInsensitiveMap(Map<String, String> carrier) {
- super(carrier);
+ if (carrier != null) {
+ this.putAll(carrier);
+ }
  }
 
  @Override
  public String put(String key, String value) {
- return super.put(key.toLowerCase(Locale.ROOT), value);
+ return super.put(getKeyLowerCase(key), value);
+ }
+
+ @Override
+ public void putAll(Map<? extends String, ? extends String> m) {
+ m.forEach(this::put);
+ }
+
+ private static String getKeyLowerCase(@Nonnull String key) {
+ return key.toLowerCase(Locale.ROOT);
  }
 
  @Override
  @Nullable
  public String get(Object key) {
- return super.get(((String) key).toLowerCase(Locale.ROOT));
+ return super.get(getKeyLowerCase((String) key));
  }
 }

api/incubator/src/test/java/io/opentelemetry/api/incubator/propagation/CaseInsensitiveMapTest.java

@@ -0,0 +1,69 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.api.incubator.propagation;
+
+import static io.opentelemetry.sdk.testing.assertj.OpenTelemetryAssertions.assertThat;
+
+import java.util.HashMap;
+import java.util.Map;
+import org.junit.jupiter.api.Test;
+
+class CaseInsensitiveMapTest {
+
+ @Test
+ void createByConstructor() {
+ Map<String, String> map = new HashMap<>();
+ map.put("Key1", "test");
+ map.put("Key2", "test2");
+
+ CaseInsensitiveMap caseInsensitiveMap = new CaseInsensitiveMap(map);
+
+ Map<String, String> standardMap = new HashMap<>();
+ standardMap.put("key1", "test");
+ standardMap.put("key2", "test2");
+
+ assertThat(caseInsensitiveMap).isEqualTo(standardMap);
+ }
+
+ @Test
+ void putAll() {
+ CaseInsensitiveMap caseInsensitiveMap = new CaseInsensitiveMap();
+ Map<String, String> standardMap = new HashMap<>();
+ standardMap.put("key1", "test");
+ standardMap.put("key2", "test2");
+ caseInsensitiveMap.putAll(standardMap);
+ assertThat(caseInsensitiveMap).isEqualTo(standardMap);
+ }
+
+ @Test
+ void putIfAbsent() {
+ CaseInsensitiveMap caseInsensitiveMap = new CaseInsensitiveMap();
+ caseInsensitiveMap.putIfAbsent("key1", "test");
+ assertThat(caseInsensitiveMap.get("KEY1")).isEqualTo("test");
+ caseInsensitiveMap.putIfAbsent("key1", "nope");
+ assertThat(caseInsensitiveMap.get("KEY1")).isEqualTo("test");
+ }
+
+ @Test
+ void createByConstructorWithNullMap() {
+ CaseInsensitiveMap caseInsensitiveMap = new CaseInsensitiveMap(null);
+ assertThat(caseInsensitiveMap).isEmpty();
+ }
+
+ @Test
+ void caseInsensitivity() {
+ CaseInsensitiveMap caseInsensitiveMap = new CaseInsensitiveMap(null);
+
+ assertThat(caseInsensitiveMap).isEmpty();
+
+ caseInsensitiveMap.put("KEY1", "test1");
+ caseInsensitiveMap.put("KEY2", "test2");
+ assertThat(caseInsensitiveMap.get("key1")).isEqualTo("test1");
+ assertThat(caseInsensitiveMap.get("key2")).isEqualTo("test2");
+ assertThat(caseInsensitiveMap.get("kEy2")).isEqualTo("test2");
+ assertThat(caseInsensitiveMap.get("KEY2")).isEqualTo("test2");
+ }
+}