UnsupportedOperationException in Java is a runtime exception that occurs when attempting to perform unsupported operations on certain objects, particularly unmodifiable or fixed-size collections. This exception is commonly encountered when using methods like Arrays.asList(), List.of(), or Collections.unmodifiableList(), which return collections that do not support modifications such as adding or removing elements. Despite being an unchecked exception, making it not mandatory to declare in method throws clauses, it can still be disruptive. The text provides examples of scenarios where this exception might arise, such as attempting to modify immutable collections or using unsupported operations on collection wrappers. It suggests solutions like converting fixed-size lists to mutable collections or using appropriate iterator methods to safely perform modifications. Additionally, it advises best practices such as choosing the right collection type, checking documentation, and employing defensive copying to avoid this exception. For error management, tools like Rollbar are recommended to automate the tracking and fixing of Java errors effectively.