diff -r 5995afcacbc3 -r f48597f265ff src/Pure/Admin/component_xz.scala
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/Pure/Admin/component_xz.scala	Mon Dec 16 19:09:14 2024 +0100
@@ -0,0 +1,97 @@
+/*  Title:      Pure/Admin/component_xz.scala
+    Author:     Makarius
+
+Build Isabelle xz-java component from official download.
+*/
+
+package isabelle
+
+
+object Component_XZ {
+  /* build xz */
+
+  val main_url = "https://tukaani.org/xz/java.html"
+  val default_source_url = "https://github.com/tukaani-project/xz-java/releases/download"
+  val default_download_url = "https://repo1.maven.org/maven2/org/tukaani/xz"
+  val default_version = "1.10"
+
+  def build_xz(
+    target_dir: Path = Path.current,
+    source_url: String = default_source_url,
+    download_url: String = default_download_url,
+    version: String = default_version,
+    progress: Progress = new Progress,
+  ): Unit = {
+    /* component */
+
+    val component_name = "xz-java-" + version
+    val component_dir =
+      Components.Directory(target_dir + Path.basic(component_name)).create(progress = progress)
+
+    File.write(component_dir.README,
+      "This is " + component_name + " from " + main_url +
+        "\n\n        Makarius\n        " + Date.Format.date(Date.now()) + "\n")
+
+    Isabelle_System.with_tmp_file("tmp", ext = "zip") { tmp =>
+      Isabelle_System.download_file(
+        source_url + "/v" + version + "/xz-java-" + version + ".zip", tmp, progress = progress)
+      Isabelle_System.extract(tmp, component_dir.path)
+    }
+
+
+    /* lib */
+
+    val jar_name = "xz-" + version + ".jar"
+
+    Isabelle_System.make_directory(component_dir.lib)
+    Isabelle_System.download_file(
+      download_url + "/" + version + "/" + jar_name,
+      component_dir.lib + Path.basic(jar_name), progress = progress)
+
+
+    /* settings */
+
+    component_dir.write_settings("""
+ISABELLE_XZ_HOME="$COMPONENT"
+
+classpath "$ISABELLE_XZ_HOME/lib/""" + jar_name + """"
+""")
+  }
+
+
+  /* Isabelle tool wrapper */
+
+  val isabelle_tool =
+    Isabelle_Tool("component_xz", "build Isabelle xz-java component from official download",
+      Scala_Project.here,
+      { args =>
+        var target_dir = Path.current
+        var source_url = default_source_url
+        var download_url = default_download_url
+        var version = default_version
+
+        val getopts = Getopts("""
+Usage: isabelle component_xz [OPTIONS]
+
+  Options are:
+    -D DIR       target directory (default ".")
+    -S URL       source URL (default: """ + quote(default_source_url) + """)
+    -U URL       download URL (default: """ + quote(default_download_url) + """)
+    -V VERSION   version (default: """ + quote(default_version) + """)
+
+  Build zxz-java component from the specified download base URL and VERSION,
+  see also """ + main_url + "\n",
+          "D:" -> (arg => target_dir = Path.explode(arg)),
+          "S:" -> (arg => source_url = arg),
+          "U:" -> (arg => download_url = arg),
+          "V:" -> (arg => version = arg))
+
+        val more_args = getopts(args)
+        if (more_args.nonEmpty) getopts.usage()
+
+        val progress = new Console_Progress()
+
+        build_xz(target_dir = target_dir, source_url = source_url,
+          download_url = download_url, version = version, progress = progress)
+      })
+}