Simplify startJVM and support PathLike types for classpath and jvmpath arguments

jpype/_classpath.py

@@ -16,6 +16,8 @@
 #
 # *****************************************************************************
 import os as _os
+import typing
+
 import _jpype
 
 __all__ = ['addClassPath', 'getClassPath']
@@ -24,7 +26,7 @@
 _SEP = _os.path.pathsep
 
 
-def addClassPath(path1):
+def addClassPath(path1: typing.Union[str, _os.PathLike]) -> None:
     """ Add a path to the Java class path
 
     Classpath items can be a java, a directory, or a
@@ -66,7 +68,7 @@ def addClassPath(path1):
     _CLASSPATHS.append(path1)
 
 
-def getClassPath(env=True):
+def getClassPath(env: bool = True) -> str:
     """ Get the full Java class path.
 
     Includes user added paths and the environment CLASSPATH.
@@ -79,7 +81,7 @@ def getClassPath(env=True):
     global _CLASSPATHS
     global _SEP
 
-    # Merge the evironment path
+    # Merge the environment path
     classPath = list(_CLASSPATHS)
     envPath = _os.environ.get("CLASSPATH")
     if env and envPath:

jpype/_core.py

@@ -15,8 +15,13 @@
 #   See NOTICE file for details.
 #
 # *****************************************************************************
-import sys
+from __future__ import annotations
+
 import atexit
+import os
+import sys
+import typing
+
 import _jpype
 from . import types as _jtypes
 from . import _classpath
@@ -53,6 +58,10 @@ class JVMNotRunning(RuntimeError):
     pass
 
 
+if typing.TYPE_CHECKING:
+    _PathOrStr = typing.Union[str, os.PathLike]
+
+
 # See http://scottlobdell.me/2015/04/decorators-arguments-python/
 def deprecated(*args):
     """ Marks a function a deprecated when used as decorator.
@@ -96,23 +105,48 @@ def isJVMStarted():
     return _jpype.isStarted()
 
 
-def _hasClassPath(args):
+def _hasClassPath(args: typing.Tuple[_PathOrStr, ...]) -> bool:
     for i in args:
-        if i.startswith('-Djava.class.path'):
+        if isinstance(i, str) and i.startswith('-Djava.class.path'):
             return True
     return False
 
 
-def _handleClassPath(clsList):
+def _handleClassPath(
+    classpath: typing.Union[
+        _PathOrStr,
+        typing.Tuple[_PathOrStr, ...]
+    ],
+) -> str:
+    """
+    Return a classpath which represents the given tuple of classpath specifications
+    """
     out = []
-    for s in clsList:
-        if not isinstance(s, str):
-            raise TypeError("Classpath elements must be strings")
-        if s.endswith('*'):
+
+    if isinstance(classpath, (str, os.PathLike)):
+        classpath = (classpath,)
+    try:
+        # Convert anything iterable into a tuple.
+        classpath = tuple(classpath)
+    except TypeError:
+        raise TypeError("Unknown class path element")
+
+    for element in classpath:
+        try:
+            pth = os.fspath(element)
+        except TypeError as err:
+            raise TypeError("Classpath elements must be strings or Path-like") from err
+
+        if isinstance(pth, bytes):
+            # In the future we may allow this to support Paths which are undecodable.
+            # https://docs.python.org/3/howto/unicode.html#unicode-filenames.
+            raise TypeError("Classpath elements must be strings or Path-like")
+
+        if pth.endswith('*'):
             import glob
-            out.extend(glob.glob(s + '.jar'))
+            out.extend(glob.glob(pth + '.jar'))
         else:
-            out.append(s)
+            out.append(pth)
     return _classpath._SEP.join(out)
 
 
@@ -123,7 +157,14 @@ def interactive():
     return bool(getattr(sys, 'ps1', sys.flags.interactive))
 
 
-def startJVM(*args, **kwargs):
+def startJVM(
+    *jvmargs: str,
+    jvmpath: typing.Optional[_PathOrStr] = None,
+    classpath: typing.Optional[_PathOrStr] = None,
+    ignoreUnrecognized: bool = False,
+    convertStrings: bool = False,
+    interrupt: bool = not interactive(),
+) -> None:
     """
     Starts a Java Virtual Machine.  Without options it will start
     the JVM with the default classpath and jvmpath.
@@ -132,14 +173,14 @@ def startJVM(*args, **kwargs):
     The default jvmpath is determined by ``jpype.getDefaultJVMPath()``.
 
     Parameters:
-     *args (Optional, str[]): Arguments to give to the JVM.
-        The first argument may be the path the JVM.
+     *jvmargs (Optional, str[]): Arguments to give to the JVM.
+        The first argument may be the path to the JVM.
 
     Keyword Arguments:
-      jvmpath (str):  Path to the jvm library file,
+      jvmpath (str, PathLike):  Path to the jvm library file,
         Typically one of (``libjvm.so``, ``jvm.dll``, ...)
         Using None will apply the default jvmpath.
-      classpath (str,[str]): Set the classpath for the JVM.
+      classpath (str, PathLike, [str, PathLike]): Set the classpath for the JVM.
         This will override any classpath supplied in the arguments
         list. A value of None will give no classpath to JVM.
       ignoreUnrecognized (bool): Option to ignore
@@ -158,8 +199,7 @@ def startJVM(*args, **kwargs):
 
     Raises:
       OSError: if the JVM cannot be started or is already running.
-      TypeError: if an invalid keyword argument is supplied
-        or a keyword argument conflicts with the arguments.
+      TypeError: if a keyword argument conflicts with the positional arguments.
 
      """
     if _jpype.isStarted():
@@ -168,51 +208,36 @@ def startJVM(*args, **kwargs):
     if _JVM_started:
         raise OSError('JVM cannot be restarted')
 
-    args = list(args)
-
     # JVM path
-    jvmpath = None
-    if args:
+    if jvmargs:
         # jvm is the first argument the first argument is a path or None
-        if not args[0] or not args[0].startswith('-'):
-            jvmpath = args.pop(0)
-    if 'jvmpath' in kwargs:
-        if jvmpath:
-            raise TypeError('jvmpath specified twice')
-        jvmpath = kwargs.pop('jvmpath')
+        if jvmargs[0] is not None and isinstance(jvmargs[0], str) and not jvmargs[0].startswith('-'):
+            if jvmpath:
+                raise TypeError('jvmpath specified twice')
+            jvmpath = jvmargs[0]
+            jvmargs = jvmargs[1:]
+
     if not jvmpath:
         jvmpath = getDefaultJVMPath()
+    else:
+        # Allow the path to be a PathLike.
+        jvmpath = os.fspath(jvmpath)
+
+    extra_jvm_args = tuple()
 
     # Classpath handling
-    if _hasClassPath(args):
+    if _hasClassPath(jvmargs):
         # Old style, specified in the arguments
-        if 'classpath' in kwargs:
+        if classpath is not None:
             # Cannot apply both styles, conflict
             raise TypeError('classpath specified twice')
-        classpath = None
-    elif 'classpath' in kwargs:
-        # New style, as a keywork
-        classpath = kwargs.pop('classpath')
-    else:
-        # Not speficied at all, use the default classpath
+    elif classpath is None:
+        # Not specified at all, use the default classpath.
         classpath = _classpath.getClassPath()
 
     # Handle strings and list of strings.
     if classpath:
-        if isinstance(classpath, str):
-            args.append('-Djava.class.path=%s' % _handleClassPath([classpath]))
-        elif hasattr(classpath, '__iter__'):
-            args.append('-Djava.class.path=%s' % _handleClassPath(classpath))
-        else:
-            raise TypeError("Unknown class path element")
-
-    ignoreUnrecognized = kwargs.pop('ignoreUnrecognized', False)
-    convertStrings = kwargs.pop('convertStrings', False)
-    interrupt = kwargs.pop('interrupt', not interactive())
-
-    if kwargs:
-        raise TypeError("startJVM() got an unexpected keyword argument '%s'"
-                        % (','.join([str(i) for i in kwargs])))
+        extra_jvm_args += (f'-Djava.class.path={_handleClassPath(classpath)}', )
 
     try:
         import locale
@@ -221,7 +246,7 @@ def startJVM(*args, **kwargs):
         # Keep the current locale settings, else Java will replace them.
         prior = [locale.getlocale(i) for i in categories]
         # Start the JVM
-        _jpype.startup(jvmpath, tuple(args),
+        _jpype.startup(jvmpath, jvmargs + extra_jvm_args,
                        ignoreUnrecognized, convertStrings, interrupt)
         # Collect required resources for operation
         initializeResources()
@@ -238,8 +263,7 @@ def startJVM(*args, **kwargs):
             match = re.search(r"([0-9]+)\.[0-9]+", source)
             if match:
                 version = int(match.group(1)) - 44
-                raise RuntimeError("%s is older than required Java version %d" % (
-                    jvmpath, version)) from ex
+                raise RuntimeError(f"{jvmpath} is older than required Java version{version}") from ex
         raise
 
 

test/jpypetest/test_startup.py

@@ -18,23 +18,20 @@
 import jpype
 import common
 import subrun
+import functools
 import os
+from pathlib import Path
 import sys
 import unittest
 
 
-def runStartJVM(*args, **kwargs):
-    jpype.startJVM(*args, **kwargs)
-
-
+@functools.wraps(jpype.startJVM)
 def runStartJVMTest(*args, **kwargs):
     jpype.startJVM(*args, **kwargs)
     try:
-        jclass = jpype.JClass('jpype.array.TestArray')
-        return
-    except:
-        pass
-    raise RuntimeError("Test class not found")
+        assert jpype.JClass('jpype.array.TestArray') is not None
+    except Exception as err:
+        raise RuntimeError("Test class not found") from err
 
 
 root = os.path.dirname(os.path.abspath(os.path.dirname(__file__)))
@@ -57,17 +54,18 @@ def testRestart(self):
             jpype.shutdownJVM()
             jpype.startJVM(convertStrings=False)
 
-    def testJVMPathKeyword(self):
-        runStartJVM(jvmpath=self.jvmpath)
-
     def testInvalidArgsFalse(self):
         with self.assertRaises(RuntimeError):
-            runStartJVM("-for_sure_InVaLiD",
-                        ignoreUnrecognized=False, convertStrings=False)
+            jpype.startJVM(
+                "-for_sure_InVaLiD",
+                ignoreUnrecognized=False, convertStrings=False,
+            )
 
     def testInvalidArgsTrue(self):
-        runStartJVM("-for_sure_InVaLiD",
-                    ignoreUnrecognized=True, convertStrings=False)
+        jpype.startJVM(
+            "-for_sure_InVaLiD",
+            ignoreUnrecognized=True, convertStrings=False,
+        )
 
     def testClasspathArgKeyword(self):
         runStartJVMTest(classpath=cp, convertStrings=False)
@@ -81,6 +79,16 @@ def testClasspathArgListEmpty(self):
     def testClasspathArgDef(self):
         runStartJVMTest('-Djava.class.path=%s' % cp, convertStrings=False)
 
+    def testClasspathArgPath(self):
+        runStartJVMTest(classpath=Path(cp), convertStrings=False)
+
+    def testClasspathArgPathList(self):
+        runStartJVMTest(classpath=[Path(cp)], convertStrings=False)
+
+    def testClasspathArgGlob(self):
+        jpype.startJVM(classpath=os.path.join(cp, '..', 'jar', 'mrjar*'))
+        assert jpype.JClass('org.jpype.mrjar.A') is not None
+
     def testClasspathTwice(self):
         with self.assertRaises(TypeError):
             runStartJVMTest('-Djava.class.path=%s' %
@@ -90,14 +98,26 @@ def testClasspathBadType(self):
         with self.assertRaises(TypeError):
             runStartJVMTest(classpath=1, convertStrings=False)
 
-    def testPathArg(self):
+    def testJVMPathArg_Str(self):
         runStartJVMTest(self.jvmpath, classpath=cp, convertStrings=False)
 
-    def testPathKeyword(self):
-        path = jpype.getDefaultJVMPath()
+    def testJVMPathArg_Path(self):
+        with self.assertRaises(TypeError):
+            runStartJVMTest([
+                # Pass a path as the first argument. This isn't supported (this is
+                # reflected in the type definition), but the fact that it "works"
+                # gives rise to this test.
+                Path(self.jvmpath), cp],  # type: ignore
+                convertStrings=False,
+            )
+
+    def testJVMPathKeyword_str(self):
         runStartJVMTest(classpath=cp, jvmpath=self.jvmpath,
                         convertStrings=False)
 
+    def testJVMPathKeyword_Path(self):
+        runStartJVMTest(jvmpath=Path(self.jvmpath), classpath=cp, convertStrings=False)
+
     def testPathTwice(self):
         with self.assertRaises(TypeError):
             jpype.startJVM(self.jvmpath, jvmpath=self.jvmpath)