python
@@ -955,6 +955,9 @@ Removed
   ``SSTATE_INTERNED_IMMORTAL`` macro.
   (Contributed by Victor Stinner in :gh:`85858`.)
 
+* Remove ``Jython`` compatibility hacks from several stdlib modules and tests.
+  (Contributed by Nikita Sobolev in :gh:`99482`.)
+
 * Remove ``_use_broken_old_ctypes_structure_semantics_`` flag
   from :mod:`ctypes` module.
   (Contributed by Nikita Sobolev in :gh:`99285`.)
diff --git a/Lib/copy.py b/Lib/copy.py
@@ -56,11 +56,6 @@ class Error(Exception):
     pass
 error = Error   # backward compatibility
 
-try:
-    from org.python.core import PyStringMap
-except ImportError:
-    PyStringMap = None
-
 __all__ = ["Error", "copy", "deepcopy"]
 
 def copy(x):
@@ -120,9 +115,6 @@ def _copy_immutable(x):
 d[set] = set.copy
 d[bytearray] = bytearray.copy
 
-if PyStringMap is not None:
-    d[PyStringMap] = PyStringMap.copy
-
 del d, t
 
 def deepcopy(x, memo=None, _nil=[]):
@@ -231,8 +223,6 @@ def _deepcopy_dict(x, memo, deepcopy=deepcopy):
         y[deepcopy(key, memo)] = deepcopy(value, memo)
     return y
 d[dict] = _deepcopy_dict
-if PyStringMap is not None:
-    d[PyStringMap] = _deepcopy_dict
 
 def _deepcopy_method(x, memo): # Copy instance methods
     return type(x)(x.__func__, deepcopy(x.__self__, memo))
@@ -301,4 +291,4 @@ def _reconstruct(x, memo, func, args,
                 y[key] = value
     return y
 
-del types, weakref, PyStringMap
+del types, weakref
diff --git a/Lib/pickle.py b/Lib/pickle.py
@@ -98,12 +98,6 @@ class _Stop(Exception):
     def __init__(self, value):
         self.value = value
 
-# Jython has PyStringMap; it's a dict subclass with string keys
-try:
-    from org.python.core import PyStringMap
-except ImportError:
-    PyStringMap = None
-
 # Pickle opcodes.  See pickletools.py for extensive docs.  The listing
 # here is in kind-of alphabetical order of 1-character pickle code.
 # pickletools groups them by purpose.
@@ -972,8 +966,6 @@ def save_dict(self, obj):
         self._batch_setitems(obj.items())
 
     dispatch[dict] = save_dict
-    if PyStringMap is not None:
-        dispatch[PyStringMap] = save_dict
 
     def _batch_setitems(self, items):
         # Helper to batch up SETITEMS sequences; proto >= 1 only

diff --git a/Lib/platform.py b/Lib/platform.py
@@ -1290,7 +1290,7 @@ def platform(aliased=0, terse=0):
         else:
             platform = _platform(system, release, version, csd)
 
-    elif system in ('Linux',):
+    elif system == 'Linux':
         # check for libc vs. glibc
         libcname, libcversion = libc_ver()
         platform = _platform(system, release, machine, processor,

@@ -404,12 +404,7 @@ def setquit():
 def setcopyright():
     """Set 'copyright' and 'credits' in builtins"""
     builtins.copyright = _sitebuiltins._Printer("copyright", sys.copyright)
-    if sys.platform[:4] == 'java':
-        builtins.credits = _sitebuiltins._Printer(
-            "credits",
-            "Jython is maintained by the Jython developers (www.jython.org).")
-    else:
-        builtins.credits = _sitebuiltins._Printer("credits", """\
+    builtins.credits = _sitebuiltins._Printer("credits", """\
     Thanks to CWI, CNRI, BeOpen.com, Zope Corporation and a cast of thousands
     for supporting Python development.  See www.python.org for more information.""")
     files, dirs = [], []

diff --git a/Lib/test/support/__init__.py b/Lib/test/support/__init__.py
@@ -505,6 +505,7 @@ def requires_debug_ranges(reason='requires co_positions / debug_ranges'):
 requires_legacy_unicode_capi = unittest.skipUnless(unicode_legacy_string,
                         'requires legacy Unicode C API')
 
+# Is not actually used in tests, but is kept for compatibility.
 is_jython = sys.platform.startswith('java')
 
 is_android = hasattr(sys, 'getandroidapilevel')
@@ -736,8 +737,6 @@ def gc_collect():
     """
     import gc
     gc.collect()
-    if is_jython:
-        time.sleep(0.1)
     gc.collect()
     gc.collect()
 

diff --git a/Lib/test/support/os_helper.py b/Lib/test/support/os_helper.py
@@ -11,11 +11,7 @@
 
 
 # Filename used for testing
-if os.name == 'java':
-    # Jython disallows @ in module names
-    TESTFN_ASCII = '$test'
-else:
-    TESTFN_ASCII = '@test'
+TESTFN_ASCII = '@test'
 
 # Disambiguate TESTFN for parallel testing, while letting it remain a valid
 # module name.

diff --git a/Lib/test/test___all__.py b/Lib/test/test___all__.py
@@ -100,10 +100,9 @@ def test_all(self):
             '__future__',
         ])
 
-        if not sys.platform.startswith('java'):
-            # In case _socket fails to build, make this test fail more gracefully
-            # than an AttributeError somewhere deep in CGIHTTPServer.
-            import _socket
+        # In case _socket fails to build, make this test fail more gracefully
+        # than an AttributeError somewhere deep in CGIHTTPServer.
+        import _socket
 
         ignored = []
         failed_imports = []

diff --git a/Lib/test/test_codeop.py b/Lib/test/test_codeop.py
@@ -2,47 +2,18 @@
    Test cases for codeop.py
    Nick Mathewson
 """
-import sys
 import unittest
 import warnings
-from test import support
 from test.support import warnings_helper
 
 from codeop import compile_command, PyCF_DONT_IMPLY_DEDENT
-import io
-
-if support.is_jython:
-
-    def unify_callables(d):
-        for n,v in d.items():
-            if hasattr(v, '__call__'):
-                d[n] = True
-        return d
 
 class CodeopTests(unittest.TestCase):
 
     def assertValid(self, str, symbol='single'):
         '''succeed iff str is a valid piece of code'''
-        if support.is_jython:
-            code = compile_command(str, "<input>", symbol)
-            self.assertTrue(code)
-            if symbol == "single":
-                d,r = {},{}
-                saved_stdout = sys.stdout
-                sys.stdout = io.StringIO()
-                try:
-                    exec(code, d)
-                    exec(compile(str,"<input>","single"), r)
-                finally:
-                    sys.stdout = saved_stdout
-            elif symbol == 'eval':
-                ctx = {'a': 2}
-                d = { 'value': eval(code,ctx) }
-                r = { 'value': eval(str,ctx) }
-            self.assertEqual(unify_callables(r),unify_callables(d))
-        else:
-            expected = compile(str, "<input>", symbol, PyCF_DONT_IMPLY_DEDENT)
-            self.assertEqual(compile_command(str, "<input>", symbol), expected)
+        expected = compile(str, "<input>", symbol, PyCF_DONT_IMPLY_DEDENT)
+        self.assertEqual(compile_command(str, "<input>", symbol), expected)
 
     def assertIncomplete(self, str, symbol='single'):
         '''succeed iff str is the start of a valid piece of code'''
@@ -62,16 +33,12 @@ def test_valid(self):
         av = self.assertValid
 
         # special case
-        if not support.is_jython:
-            self.assertEqual(compile_command(""),
-                             compile("pass", "<input>", 'single',
-                                     PyCF_DONT_IMPLY_DEDENT))
-            self.assertEqual(compile_command("\n"),
-                             compile("pass", "<input>", 'single',
-                                     PyCF_DONT_IMPLY_DEDENT))
-        else:
-            av("")
-            av("\n")
+        self.assertEqual(compile_command(""),
+                            compile("pass", "<input>", 'single',
+                                    PyCF_DONT_IMPLY_DEDENT))
+        self.assertEqual(compile_command("\n"),
+                            compile("pass", "<input>", 'single',
+                                    PyCF_DONT_IMPLY_DEDENT))
 
         av("a = 1")
         av("\na = 1")

@@ -360,10 +360,9 @@ def test_capi3():
             self.assertRaises(SystemError, _testcapi.raise_exception,
                               InvalidException, 1)
 
-        if not sys.platform.startswith('java'):
-            test_capi1()
-            test_capi2()
-            test_capi3()
+        test_capi1()
+        test_capi2()
+        test_capi3()
 
     def test_WindowsError(self):
         try:

@@ -20,7 +20,7 @@
 
 from test.support import os_helper
 from test.support import (
-    STDLIB_DIR, is_jython, swap_attr, swap_item, cpython_only, is_emscripten,
+    STDLIB_DIR, swap_attr, swap_item, cpython_only, is_emscripten,
     is_wasi)
 from test.support.import_helper import (
     forget, make_legacy_pyc, unlink, unload, DirsOnSysPath, CleanImport)
@@ -163,10 +163,7 @@ def test_import(self):
         def test_with_extension(ext):
             # The extension is normally ".py", perhaps ".pyw".
             source = TESTFN + ext
-            if is_jython:
-                pyc = TESTFN + "$py.class"
-            else:
-                pyc = TESTFN + ".pyc"
+            pyc = TESTFN + ".pyc"
 
             with open(source, "w", encoding='utf-8') as f:
                 print("# This tests Python's ability to import a",

diff --git a/Lib/test/test_platform.py b/Lib/test/test_platform.py
@@ -329,7 +329,7 @@ def raises_oserror(*a):
 
     def test_java_ver(self):
         res = platform.java_ver()
-        if sys.platform == 'java':
+        if sys.platform == 'java':  # Is never actually checked in CI
             self.assertTrue(all(res))
 
     def test_win32_ver(self):

@@ -54,14 +54,10 @@ def _update_variables(self, now):
         self.now = now
 
     def setUp(self):
-        try:
-            import java
-            java.util.Locale.setDefault(java.util.Locale.US)
-        except ImportError:
-            from locale import setlocale, LC_TIME
-            saved_locale = setlocale(LC_TIME)
-            setlocale(LC_TIME, 'C')
-            self.addCleanup(setlocale, LC_TIME, saved_locale)
+        from locale import setlocale, LC_TIME
+        saved_locale = setlocale(LC_TIME)
+        setlocale(LC_TIME, 'C')
+        self.addCleanup(setlocale, LC_TIME, saved_locale)
 
     def test_strftime(self):
         now = time.time()