Project Loom Lab

Experiments with Project Loom's features based on these JEPs:

• JEP 425: Virtual Threads
• JEP 428: Structured Concurrency

Experiments

• Disk Stats
• Echo Client & Server
• GitHub Crawler

For these experiments, you need Java 19. Build the project with mvn package to get target/loom-lab.jar. To run it:

java --enable-preview -p target/loom-lab.jar -m loom.lab $EXPERIMENT $ARGUMENTS

Where:

• $EXPERIMENT selects one of the experiments by name
• $ARGUMENTS configures the experiment

For details on these, see specific experiments below.

Disk Stats

Walks over all folders and files in a given directory to gather their respective sizes. Can be configured to either run as a single thread or with one virtual thread for each file/folder.

• name: DiskStats
• arguments: see DiskStats.java.
• package: dev.nipafx.lab.loom.disk

Echo Client & Server

A client and server that exchange messages via sockets on localhost:8080. Client protocol:

• sends a single line, terminated by a newline
• waits for a single line (i.e. a string terminated by a newline) to be received

Server protocol:

• reads a single line (i.e. a string terminated by a newline) from that socket
• waits a predetermined amount of time
• replies with the same string, including the newline

To try this out, run the client and the server in different shells.

• server
  • name: EchoServer
  • arguments: see Echo.java.
• client
  • name: EchoClient
  • arguments: see Send.java.,
• package: dev.nipafx.lab.loom.echo

Note: For a much more thorough experiment with an echo server, check out Elliot Barlas' project-loom-experiment.

GitHub Crawler

Starting from a given seed URL, crawls GitHub pages and prints their connections and statistics. Only runs with virtual threads but also uses/demonstrates some Data-Oriented Programming concepts.

• name: GitHubCrawl
• arguments: see GitHubCrawl.java.
• package: dev.nipafx.lab.loom.crawl