Move Entity and EntityBuilder to be pure interfaces

Author: jsuereth

sdk/common/src/main/java/io/opentelemetry/sdk/resources/internal/Entity.java

@@ -5,7 +5,6 @@
 
 package io.opentelemetry.sdk.resources.internal;
 
-import com.google.auto.value.AutoValue;
 import io.opentelemetry.api.common.Attributes;
 import javax.annotation.Nullable;
 import javax.annotation.concurrent.Immutable;
@@ -27,8 +26,7 @@
  * at any time.
  */
 @Immutable
-@AutoValue
-public abstract class Entity {
+public interface Entity {
   /**
    * Returns the entity type string of this entity. Must not be null.
    *
@@ -60,38 +58,17 @@ public abstract class Entity {
   @Nullable
   public abstract String getSchemaUrl();
 
-  /**
-   * Returns a {@link Entity}.
-   *
-   * @param entityType the entity type string of this entity.
-   * @param id a map of attributes that identify the entity.
-   * @param description a map of attributes that describe the entity.
-   * @return a {@code Entity}.
-   * @throws NullPointerException if {@code id} or {@code description} is null.
-   * @throws IllegalArgumentException if entityType string, attribute key or attribute value is not
-   *     a valid printable ASCII string or exceed {@link AttributeCheckUtil#MAX_LENGTH} characters.
-   */
-  static final Entity create(
-      String entityType, Attributes id, Attributes description, @Nullable String schemaUrl) {
-    AttributeCheckUtil.isValid(entityType);
-    AttributeCheckUtil.checkAttributes(id);
-    AttributeCheckUtil.checkAttributes(description);
-    return new AutoValue_Entity(entityType, id, description, schemaUrl);
-  }
-
   /**
    * Returns a new {@link EntityBuilder} instance populated with the data of this {@link Entity}.
    */
-  public final EntityBuilder toBuilder() {
-    return new EntityBuilder(this);
-  }
+  EntityBuilder toBuilder();
 
   /**
    * Returns a new {@link EntityBuilder} instance for creating arbitrary {@link Entity}.
    *
    * @param entityType the entity type string of this entity.
    */
-  public static final EntityBuilder builder(String entityType) {
-    return new EntityBuilder(entityType);
+  public static EntityBuilder builder(String entityType) {
+    return SdkEntity.builder(entityType);
   }
 }

sdk/common/src/main/java/io/opentelemetry/sdk/resources/internal/EntityBuilder.java

@@ -8,7 +8,6 @@
 import io.opentelemetry.api.common.Attributes;
 import io.opentelemetry.api.common.AttributesBuilder;
 import java.util.function.Consumer;
-import javax.annotation.Nullable;
 
 /**
  * A builder of {@link Entity} that allows to add identifying or descriptive {@link Attributes}, as
@@ -17,60 +16,31 @@
  * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
  * at any time.
  */
-public final class EntityBuilder {
-  private final String entityType;
-  private final AttributesBuilder descriptionBuilder;
-  private final AttributesBuilder idBuilder;
-  @Nullable private String schemaUrl;
-
-  EntityBuilder(String entityType) {
-    this.entityType = entityType;
-    this.descriptionBuilder = Attributes.builder();
-    this.idBuilder = Attributes.builder();
-  }
-
-  EntityBuilder(Entity seed) {
-    this.entityType = seed.getType();
-    this.schemaUrl = seed.getSchemaUrl();
-    this.idBuilder = seed.getId().toBuilder();
-    this.descriptionBuilder = seed.getDescription().toBuilder();
-  }
-
+public interface EntityBuilder {
   /**
    * Assign an OpenTelemetry schema URL to the resulting Entity.
    *
    * @param schemaUrl The URL of the OpenTelemetry schema being used to create this Entity.
    * @return this
    */
-  public EntityBuilder setSchemaUrl(String schemaUrl) {
-    this.schemaUrl = schemaUrl;
-    return this;
-  }
+  EntityBuilder setSchemaUrl(String schemaUrl);
 
   /**
    * Modify the descriptive attributes of this Entity.
    *
    * @param f A thunk which manipulates descriptive attributes.
    * @return this
    */
-  public EntityBuilder withDescription(Consumer<AttributesBuilder> f) {
-    f.accept(this.descriptionBuilder);
-    return this;
-  }
+  EntityBuilder withDescription(Consumer<AttributesBuilder> f);
 
   /**
    * Modify the identifying attributes of this Entity.
    *
    * @param f A thunk which manipulates identifying attributes.
    * @return this
    */
-  public EntityBuilder withId(Consumer<AttributesBuilder> f) {
-    f.accept(this.idBuilder);
-    return this;
-  }
+  EntityBuilder withId(Consumer<AttributesBuilder> f);
 
   /** Create the {@link Entity} from this. */
-  public Entity build() {
-    return Entity.create(entityType, idBuilder.build(), descriptionBuilder.build(), schemaUrl);
-  }
+  Entity build();
 }

sdk/common/src/main/java/io/opentelemetry/sdk/resources/internal/SdkEntity.java

@@ -0,0 +1,54 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.sdk.resources.internal;
+
+import com.google.auto.value.AutoValue;
+import io.opentelemetry.api.common.Attributes;
+import javax.annotation.Nullable;
+import javax.annotation.concurrent.Immutable;
+
+/**
+ * SDK implementation of Entity.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+@Immutable
+@AutoValue
+public abstract class SdkEntity implements Entity {
+  /**
+   * Returns a {@link Entity}.
+   *
+   * @param entityType the entity type string of this entity.
+   * @param id a map of attributes that identify the entity.
+   * @param description a map of attributes that describe the entity.
+   * @return a {@code Entity}.
+   * @throws NullPointerException if {@code id} or {@code description} is null.
+   * @throws IllegalArgumentException if entityType string, attribute key or attribute value is not
+   *     a valid printable ASCII string or exceed {@link AttributeCheckUtil#MAX_LENGTH} characters.
+   */
+  static final Entity create(
+      String entityType, Attributes id, Attributes description, @Nullable String schemaUrl) {
+    AttributeCheckUtil.isValid(entityType);
+    AttributeCheckUtil.checkAttributes(id);
+    AttributeCheckUtil.checkAttributes(description);
+    return new AutoValue_SdkEntity(entityType, id, description, schemaUrl);
+  }
+
+  @Override
+  public final EntityBuilder toBuilder() {
+    return new SdkEntityBuilder(this);
+  }
+
+  /**
+   * Returns a new {@link EntityBuilder} instance for creating arbitrary {@link Entity}.
+   *
+   * @param entityType the entity type string of this entity.
+   */
+  public static final EntityBuilder builder(String entityType) {
+    return new SdkEntityBuilder(entityType);
+  }
+}

sdk/common/src/main/java/io/opentelemetry/sdk/resources/internal/SdkEntityBuilder.java

@@ -0,0 +1,61 @@
+/*
+ * Copyright The OpenTelemetry Authors
+ * SPDX-License-Identifier: Apache-2.0
+ */
+
+package io.opentelemetry.sdk.resources.internal;
+
+import io.opentelemetry.api.common.Attributes;
+import io.opentelemetry.api.common.AttributesBuilder;
+import java.util.function.Consumer;
+import javax.annotation.Nullable;
+
+/**
+ * A builder of {@link Entity} that allows to add identifying or descriptive {@link Attributes}, as
+ * well as type and schema_url.
+ *
+ * <p>This class is internal and is hence not for public use. Its APIs are unstable and can change
+ * at any time.
+ */
+public final class SdkEntityBuilder implements EntityBuilder {
+  private final String entityType;
+  private final AttributesBuilder descriptionBuilder;
+  private final AttributesBuilder idBuilder;
+  @Nullable private String schemaUrl;
+
+  SdkEntityBuilder(String entityType) {
+    this.entityType = entityType;
+    this.descriptionBuilder = Attributes.builder();
+    this.idBuilder = Attributes.builder();
+  }
+
+  SdkEntityBuilder(Entity seed) {
+    this.entityType = seed.getType();
+    this.schemaUrl = seed.getSchemaUrl();
+    this.idBuilder = seed.getId().toBuilder();
+    this.descriptionBuilder = seed.getDescription().toBuilder();
+  }
+
+  @Override
+  public EntityBuilder setSchemaUrl(String schemaUrl) {
+    this.schemaUrl = schemaUrl;
+    return this;
+  }
+
+  @Override
+  public EntityBuilder withDescription(Consumer<AttributesBuilder> f) {
+    f.accept(this.descriptionBuilder);
+    return this;
+  }
+
+  @Override
+  public EntityBuilder withId(Consumer<AttributesBuilder> f) {
+    f.accept(this.idBuilder);
+    return this;
+  }
+
+  @Override
+  public Entity build() {
+    return SdkEntity.create(entityType, idBuilder.build(), descriptionBuilder.build(), schemaUrl);
+  }
+}