Comprehensive and Detailed Explanation:

The OIC File Server is an embedded SFTP server for file operations within the same instance. Let’s analyze each adapter:

Option A: File Adapter

Correct (Answer):The File Adapter is explicitly designed to interact with the OIC File Server. In an integration flow, you configure a File Adapter connection with the “Invoke” role, selecting the File Server as the target. For example, you could use a “Write File” operation to send a CSV file (e.g., sales_data.csv) to a folder like /uploads on the File Server. This adapter leverages SFTP under the hood, making it the native choice for internal file transfers within OIC, offering seamless integration without external dependencies.

Option B: Local Adapter

Incorrect:There’s no “Local Adapter” in OIC’s standard adapter suite. This might be a misnomer or confusion with other concepts (e.g., local invokes in orchestration), but no such adapter exists for File Server interaction.

Option C: FTP Adapter

Incorrect:The FTP Adapter connects to external FTP/SFTP servers, not the embedded OIC File Server. While it supports similar operations (e.g., write, read), its configuration requires external server details (host, port, credentials), making it unsuitable for the internal File Server, which is pre-configured within OIC.

Option D: REST Adapter

Incorrect:The REST Adapter handles HTTP-based APIs, not file transfers to the File Server. While you could theoretically use REST to manage File Server metadatavia management APIs (with ServiceAdministrator role), it’s not designed for direct file operations like sending a file, which is the question’s focus.

Why A is the Answer:The File Adapter is purpose-built for the OIC File Server, providing a direct, efficient, and supported method for internal file operations.

Edge Case:If the File Server is disabled (default state in new instances), you’d need to enable it first in Settings before the File Adapter can connect.

Use Case Example:An integration processes a payroll report and uses the File Adapter to write it to the File Server for audit purposes.

Potential Pitfall:Misconfiguring the File Adapter with external SFTP settings instead of selecting “File Server” would fail, as it’s an internal target.