Update to jgo v2

Author: ctrueden

README.md

@@ -4,7 +4,7 @@
 Supercharged Java access from Python.
 
 Built on [JPype](https://jpype.readthedocs.io/en/latest/)
-and [jgo](https://github.com/scijava/jgo).
+and [jgo](https://github.com/apposed/jgo).
 
 ## Use Java classes from Python
 
@@ -83,7 +83,7 @@ u'1.8.0_152-release'
 +++oo*OO######OO*oo+++++oo*OO######OO*oo+++++oo*OO######OO*oo+++
 ```
 
-See the [jgo documentation](https://github.com/scijava/jgo) for more about Maven endpoints.
+See the [jgo documentation](https://github.com/apposed/jgo) for more about Maven endpoints.
 
 ## Bootstrap a Java installation
 

pyproject.toml

@@ -33,8 +33,7 @@ classifiers = [
 requires-python = ">=3.9"
 dependencies = [
     "jpype1 >= 1.3.0",
-    "jgo",
-    "cjdk",
+    "jgo>=2.0.0",
 ]
 
 [dependency-groups]

src/scyjava/_cjdk_fetch.py

@@ -0,0 +1,98 @@
+"""
+Utility functions for fetching JDK/JRE.
+"""
+
+from __future__ import annotations
+
+import logging
+import os
+import subprocess
+from typing import TYPE_CHECKING, Union
+
+import jpype
+
+from jgo.exec import JavaLocator, JavaSource
+
+import scyjava.config
+
+if TYPE_CHECKING:
+    from pathlib import Path
+
+_logger = logging.getLogger(__name__)
+
+
+def ensure_jvm_available() -> None:
+    """
+    Ensure that the JVM is available.
+    """
+    fetch = scyjava.config.get_fetch_java()
+    if fetch == "never":
+        # Not allowed to fetch Java.
+        return
+    if fetch == "always" or not is_jvm_available():
+        fetch_java()
+
+
+def is_jvm_available() -> bool:
+    """Return True if the JVM is available, suppressing stderr on macos."""
+    from unittest.mock import patch
+
+    subprocess_check_output = subprocess.check_output
+
+    def _silent_check_output(*args, **kwargs):
+        # also suppress stderr on calls to subprocess.check_output
+        kwargs.setdefault("stderr", subprocess.DEVNULL)
+        return subprocess_check_output(*args, **kwargs)
+
+    try:
+        with patch.object(subprocess, "check_output", new=_silent_check_output):
+            jpype.getDefaultJVMPath()
+    # on Darwin, may raise a CalledProcessError when invoking `/usr/libexec/java_home`
+    except (jpype.JVMNotFoundException, subprocess.CalledProcessError):
+        return False
+    return True
+
+
+def fetch_java(vendor: str | None = None, version: str | None = None) -> None:
+    """
+    Fetch Java and configure PATH/JAVA_HOME.
+
+    Supports cjdk version syntax including "11", "17", "11+", "17+", etc.
+    See https://pypi.org/project/cjdk for more information.
+    """
+    if vendor is None:
+        vendor = scyjava.config.get_java_vendor()
+    if version is None:
+        version = scyjava.config.get_java_version()
+
+    _logger.info(f"Fetching {vendor}:{version}...")
+
+    locator = JavaLocator(
+        java_source=JavaSource.AUTO,
+        java_version=version,  # Pass string directly (e.g. "11", "17", "11+", "17+")
+        java_vendor=vendor,
+        verbose=True,
+    )
+
+    # Locate returns path to java executable (e.g., /path/to/java/bin/java)
+    java_exe = locator.locate()
+    java_home = java_exe.parent.parent  # Navigate from bin/java to JAVA_HOME
+
+    _logger.debug(f"java_home -> {java_home}")
+    _add_to_path(str(java_home / "bin"), front=True)
+    os.environ["JAVA_HOME"] = str(java_home)
+
+
+def _add_to_path(path: Union[Path, str], front: bool = False) -> None:
+    """Add a path to the PATH environment variable.
+
+    If front is True, the path is added to the front of the PATH.
+    By default, the path is added to the end of the PATH.
+    If the path is already in the PATH, it is not added again.
+    """
+
+    current_path = os.environ.get("PATH", "")
+    if (path := str(path)) in current_path:
+        return
+    new_path = [path, current_path] if front else [current_path, path]
+    os.environ["PATH"] = os.pathsep.join(new_path)

src/scyjava/_jdk_fetch.py

@@ -15,11 +15,11 @@
 
 import jpype
 import jpype.config
-from jgo import jgo
+import jgo
 
 import scyjava.config
 from scyjava.config import Mode, mode
-from scyjava._cjdk_fetch import ensure_jvm_available
+from scyjava._jdk_fetch import ensure_jvm_available
 
 _logger = logging.getLogger(__name__)
 
@@ -151,23 +151,31 @@ def start_jvm(options: Sequence[str] = None) -> None:
     # use the logger to notify user that endpoints are being added
     _logger.debug("Adding jars from endpoints {0}".format(endpoints))
 
-    # download JDK/JRE and Maven as appropriate
+    # download Java as appropriate
     ensure_jvm_available()
 
     # get endpoints and add to JPype class path
     if len(endpoints) > 0:
+        # sort endpoints list, except for the first one
         endpoints = endpoints[:1] + sorted(endpoints[1:])
         _logger.debug("Using endpoints %s", endpoints)
-        _, workspace = jgo.resolve_dependencies(
-            "+".join(endpoints),
-            m2_repo=scyjava.config.get_m2_repo(),
+
+        # join endpoints list to single concatenated endpoint
+        endpoint = "+".join(endpoints)
+
+        env = jgo.build(
+            endpoint=endpoint,
+            #update=False,
             cache_dir=scyjava.config.get_cache_dir(),
-            manage_dependencies=scyjava.config.get_manage_deps(),
             repositories=repositories,
-            verbose=scyjava.config.get_verbose(),
-            shortcuts=scyjava.config.get_shortcuts(),
+            # The following obsolete arguments are from jgo v1:
+            #m2_repo=scyjava.config.get_m2_repo(),
+            #manage_dependencies=scyjava.config.get_manage_deps(),
+            #verbose=scyjava.config.get_verbose(),
+            #shortcuts=scyjava.config.get_shortcuts(),
         )
-        jpype.addClassPath(os.path.join(workspace, "*"))
+        jpype.addClassPath(env.modules_dir / "*")
+        jpype.addClassPath(env.jars_dir / "*")
 
     # HACK: Try to set JAVA_HOME if it isn't already.
     if (