JDK 26 adds HttpRequest.BodyPublishers.ofFileChannel, letting developers read specific file segments directly from a shared FileChannel without copying data into heap memory, dramatically reducing memory usage and simplifying parallel chunk uploads to object storage such as OSS or S3.
This article explains the fundamentals of Java NIO, showing how to use Channels and ByteBuffer to efficiently read, write, and manipulate large files, including memory‑mapped files and RandomAccessFile alternatives, with clear code examples and step‑by‑step guidance.
Learn five Java file copy techniques—from basic streams to NIO Files.copy, FileChannel, and RandomAccessFile—detailing their implementations, performance differences, and ideal use cases for small, large, and massive files, helping you choose the most efficient method for your project.
This article examines the internal read/write mechanisms of Java's FileChannel and MappedByteBuffer on Linux kernel 5.4, compares their performance through detailed source analysis and benchmarks, and explains why MappedByteBuffer often outperforms FileChannel for small I/O but can be overtaken for larger transfers due to page‑fault and dirty‑page handling.
This article explains the concept of zero‑copy, how it eliminates redundant data copying in I/O operations, and demonstrates its implementation in Java through buffers, mmap+write, Sendfile, MappedByteBuffer, DirectByteBuffer, channel‑to‑channel transfers, and Netty’s composite buffers.
This article provides a comprehensive guide to Java NIO, covering its core components—Channel, Buffer, and Selector—explaining the differences from traditional IO, demonstrating file, socket, and server implementations with detailed code samples, and illustrating advanced features such as memory‑mapped files, scatter/gather, and pipe communication.
Java NIO's Channel API offers bidirectional, asynchronous read/write operations using Buffers, with implementations such as FileChannel, DatagramChannel, SocketChannel, and ServerSocketChannel, and the article provides a practical FileChannel example illustrating buffer handling and the essential buf.flip() step.
This article explains Java NIO introduced in Java 1.4, covering its core components—Channels, Buffers, and Selectors—detailing channel types, buffer operations, non‑blocking behavior, selector usage, and code examples such as FileChannel and Pipe, and compares NIO with classic IO.
