Maven builds get an empty okhttp jar

Using

<dependency>
    <groupId>com.squareup</groupId>
    <artifactId>square</artifactId>
    <version>47.0.1.20260715</version>
    <scope>compile</scope>
</dependency>

The resulting jar gets an empty okhttp jar. We now need to add

<dependency>
    <groupId>com.squareup.okhttp3</groupId>
    <artifactId>okhttp-jvm</artifactId>
    <version>5.2.1</version>
</dependency>

for the build to work.

Some additional detail on the failure and root cause:

Symptom — any Maven-built app using SDK 47.x fails at runtime the first time a client is built:

  java.lang.ClassNotFoundException: okhttp3.Interceptor
      at com.squareup.square.core.ClientOptions.builder(ClientOptions.java:102)
      at com.squareup.square.SquareClientBuilder.buildClientOptions(SquareClientBuilder.java:104)
      at com.squareup.square.SquareClientBuilder.build(SquareClientBuilder.java:255)

Root cause — the SDK depends on com.squareup.okhttp3:okhttp 5.x, which is published as a Kotlin Multiplatform artifact. The root okhttp jar on Maven Central contains no classes (just META-INF/kotlin-project-structure-metadata.json); the real JVM classes live in okhttp-jvm.
Gradle resolves the redirect via Gradle Module Metadata, but Maven ignores .module files, so Maven consumers silently get the empty jar.
Per the OkHttp README (https://github.com/square/okhttp#requirements), "Maven projects must select between okhttp-jvm and okhttp-android" — see also square/okhttp#8913.

Suggested fix — declare com.squareup.okhttp3:okhttp-jvm in the SDK's published POM so the correct artifact flows transitively to Maven consumers. This is how OpenTelemetry resolved the identical breakage (open-telemetry/opentelemetry-java#7491), and it matches what okio itself does: okio's root POM declares okio-jvm as a plain compile dependency, which is why okio classes resolve fine under Maven while okhttp's don't.

issue にある Maven 依存関係宣言で失敗を再現し、公開された POM とその推移的依存関係を調査します。ClientOptions.builder のスタックトレースをエントリーポイントとして使用します。完了の条件は、Maven コンシューマーが okhttp-jvm を推移的に受け取り、okhttp3.Interceptor に対する ClassNotFoundException が発生しなくなることです。