jnr-fuse is a FUSE implementation in java using Java Native Runtime (JNR).

The main goal of the project is to provide an easy way to create a high-performance filesystem in userspace.

FUSE (Filesystem in Userspace) is an OS mechanism for unix-like OS that lets non-privileged users create their own file systems without editing kernel code.

Java Native Runtime (JNR) is high-performance Java API for binding native libraries and native memory.

Prior to 0.5.5, jnr-fuse was only available in JCenter. Due to sunsetting of JCenter, starting from 0.5.5 is available in maven central.

dependencies {
    compile 'com.github.serceman:jnr-fuse:0.5.7'
}

<dependencies>
    <dependency>
        <groupId>com.github.serceman</groupId>
        <artifactId>jnr-fuse</artifactId>
        <version>0.5.7</version>
    </dependency>
</dependencies>

For implementing your own filesystem you just need to extend FuseStubFS class and implement methods you need.

See some examples.

See blog article about the implementation

• Alluxio: Alluxio is a memory-centric distributed storage system
• Cryptomator: A user-friendly encryption tool for cloud storage services
• mux2fs: Muxes subtitles into Matroska files as a FUSE filesystem
• healthcare-api-dicom-fuse: FUSE plugin for the Google Cloud Healthcare DICOM API

See instructions.