### Instruction: From the passage provided, extract the programming languages supported by Flink. Separate them with a comma.
### Input: Flink provides a high-throughput, low-latency streaming engine as well as support for event-time processing and state management. Flink applications are fault-tolerant in the event of machine failure and support exactly-once semantics. Programs can be written in Java, Scala, Python, and SQL and are automatically compiled and optimized into dataflow programs that are executed in a cluster or cloud environment.
### Response: Java, Scala, Python, SQL