Download and configure TASSEL JAR files

Downloads TASSEL and caches it locally. This only needs to be run once per TASSEL version; subsequent package loads use the cached JARs automatically.

Releases come from Maven Central by default. The standalone archives on the TASSEL GitHub releases page can be used instead, which is the only way to obtain a nightly build.

Usage

setupTASSEL(version = NULL, force = FALSE, source = c("maven", "github"))

Arguments

version

Which TASSEL release to install. For source = "maven", a version string, defaulting to the version pinned by this release of rTASSEL. For source = "github", either "nightly" (the newest nightly build, the default), "latest" (the newest tagged release), a release tag such as "dev-20260801", or a nightly version such as "5.2.98-dev.20260801".

force

If TRUE, discard any cached copy and re-download. Defaults to FALSE.

source

Where to download from: "maven" for Maven Central (the default) or "github" for a standalone archive from the TASSEL releases page.

Value

The path to the JAR cache directory (invisibly).

Details

Maven Central publishes TASSEL in one of two layouts, and the appropriate one is detected automatically:

Fat JAR

Releases up to 5.2.96 ship a single jar-with-dependencies archive containing every dependency.

Thin JAR

Later releases ship only TASSEL's own classes, so its dependencies are resolved from the POM and downloaded alongside it. This pulls artifacts from Maven Central, SciJava, and JBoss, since no single repository serves the whole graph.

GitHub standalone archives bundle sTASSEL.jar together with every dependency, so no resolution is needed. Nightly builds are cut from the develop branch and are only published there; they are unstable by construction and are best pinned to an exact version once a session depends on one.

Files are cached under the standard R user cache directory (see R_user_dir) at ~/.cache/R/rTASSEL/java/<version>/ (Linux), ~/Library/Caches/org.R-project.R/R/rTASSEL/java/<version>/ (macOS), or the equivalent on Windows. Nightly builds live beside released versions under their full version, as in java/5.2.98-dev.20260801/, so both can be installed at once and switched between with options(rTASSEL.tassel.version = ...).

Every download is verified against its published checksum: SHA-1 for Maven artifacts and SHA-256 for GitHub assets.

On success the version is recorded as active, so the next library(rTASSEL) loads it.

Examples

if (FALSE) { # \dontrun{
## Download the default TASSEL version
setupTASSEL()

## Install a specific version
setupTASSEL(version = "5.2.96")

## Force re-download
setupTASSEL(force = TRUE)

## Install the newest nightly build from GitHub
setupTASSEL(source = "github")

## Pin a specific nightly build
setupTASSEL(version = "5.2.98-dev.20260801", source = "github")
} # }