Java Open-Source frameworks for distributed systems provide robust solutions for building scalable, resilient, and high-performance applications. Frameworks like Apache Spark, Apache Hadoop, and Apache Flink offer in-memory data processing, distributed storage and processing of large datasets, and low-latency stream processing capabilities. Other frameworks like Apache ZooKeeper, Hazelcast, Akka, and RabbitMQ provide distributed services and facilitate communication between applications. Additionally, there are frameworks like Apache Kafka, Spring Cloud, and Jakarta EE that offer support for building real-time data pipelines, distributed systems patterns, and enterprise-grade distributed applications. Choosing the best framework depends on the specific needs and objectives of a project.