The Java Stream API was introduced in Java 8, allowing developers to express computations in a functional style by defining a pipeline of data-processing operations. Despite the growing importance of this API, there is a lack of benchmarks specifically targeting stream-based applications. Instead of designing and implementing new ad-hoc workloads for the Java Stream API, we propose to automatically translate existing data-processing workloads. To this end, we present S2S, an automatic benchmark generator for the Java Stream API. S2S is a SQL query compiler that converts existing workloads designed for relational databases to stream-based code. We use S2S to generate BSS, the first benchmark suite for the Java Stream API.