1. File Streamshistorical

    Writing, reading, and metadata for file streams.

  2. Fileshistorical

    Check whether a file exists, create directories, copy files, move or rename files, delete files, and recursively traverse files.

  3. Heartbeat Mechanismhistorical

    For servers, periodically clear idle channels; for clients, detect disconnected sessions and whether to reconnect.

  4. BIO Serverhistorical

    1. Example: server and client. 2. Reference.

  5. 3.15 NIOhistorical

    Basic concepts: Channel and Buffer, Channel, Buffer, NIO, and Selector.

  6. Packet Protocolhistorical

    What sticky packets and split packets are, why the phenomenon appears with TCP byte streams, and how application-layer framing solves it.

  7. Pathhistorical

    What Path is, absolute paths, and relative paths.

  8. NIO Serverhistorical

    1. Example: server and client. 2. Reference.

  9. enumhistorical

    What enum is, how to use it, and a source-level look at java.lang.Enum.

  10. switchhistorical

    Supported types and source analysis of switch over int, char, and String.