Use lower-level zipimporter rather than zipfile module for importing from JAR files

Author: timfel

graalpython/com.oracle.graal.python.test/src/tests/test_interop.py

@@ -349,24 +349,58 @@ def test_java_imports():
                 assert sun.misc.Signal is not None
 
     def test_java_import_from_jar():
-        import sys
-        import tempfile
-        import zipfile
-
-        tempname = tempfile.mktemp() + ".jar"
-        with zipfile.ZipFile(tempname, mode="w") as z:
-            with z.open("scriptDir/test_java_jar_import.py", mode="w") as member:
-                member.write(b"MEMBER = 42\n")
-        try:
-            sys.path.append(tempname + "!scriptDir")
+        if sys.graal_python_jython_emulation_enabled:
+            import tempfile
+            import zipfile
+
+            # import a single file with jar!prefix/
+            tempname = tempfile.mktemp() + ".jar"
+            with zipfile.ZipFile(tempname, mode="w") as z:
+                with z.open("scriptDir/test_java_jar_import.py", mode="w") as member:
+                    member.write(b"MEMBER = 42\n")
+            try:
+                sys.path.append(tempname + "!scriptDir")
+                try:
+                    import test_java_jar_import
+                    assert test_java_jar_import.MEMBER == 42
+                    assert test_java_jar_import.__path__ == tempname + "/scriptDir/test_java_jar_import.py"
+                finally:
+                    sys.path.pop()
+            finally:
+                os.unlink(tempname)
+
+            # import a single file with jar!/prefix/
+            tempname = tempfile.mktemp() + ".jar"
+            with zipfile.ZipFile(tempname, mode="w") as z:
+                with z.open("scriptDir/test_java_jar_import_2.py", mode="w") as member:
+                    member.write(b"MEMBER = 43\n")
             try:
-                import test_java_jar_import
-                assert test_java_jar_import.MEMBER == 42
-                assert test_java_jar_import.__path__ == tempname + "!scriptDir/test_java_jar_import.py"
+                sys.path.append(tempname + "!/scriptDir")
+                try:
+                    import test_java_jar_import_2
+                    assert test_java_jar_import_2.MEMBER == 43
+                    assert test_java_jar_import_2.__path__ == tempname + "/scriptDir/test_java_jar_import_2.py"
+                finally:
+                    sys.path.pop()
             finally:
-                sys.path.pop()
-        finally:
-            os.unlink(tempname)
+                os.unlink(tempname)
+
+            # import a package with jar!/prefix/
+            tempname = tempfile.mktemp() + ".jar"
+            with zipfile.ZipFile(tempname, mode="w") as z:
+                with z.open("scriptDir/test_java_jar_pkg/__init__.py", mode="w") as member:
+                    member.write(b"MEMBER = 44\n")
+            try:
+                sys.path.append(tempname + "!/scriptDir")
+                try:
+                    import test_java_jar_pkg
+                    assert test_java_jar_pkg.MEMBER == 44
+                    assert test_java_jar_pkg.__path__ == tempname + "/scriptDir/test_java_jar_pkg/__init__.py"
+                finally:
+                    sys.path.pop()
+            finally:
+                os.unlink(tempname)
+
 
     def test_java_exceptions():
         if sys.graal_python_jython_emulation_enabled:

graalpython/lib-graalpython/java.py

@@ -166,46 +166,32 @@ def find_spec(self, fullname, path, target=None):
 
 if sys.graal_python_jython_emulation_enabled:
     class JarImportLoader:
-        def __init__(self, jarpath, zippath):
-            self.jarpath = jarpath
-            self.zippath = zippath
+        def __init__(self, code):
+            self.code = code
 
         def create_module(self, spec):
             newmod = _frozen_importlib._new_module(spec.name)
-            newmod.__path__ = "%s!%s" % (self.jarpath, self.zippath)
+            newmod.__path__ = self.code.co_filename
             return newmod
 
         def exec_module(self, module):
-            import zipfile
-            with zipfile.ZipFile(self.jarpath) as z:
-                code = z.read(self.zippath)
-            exec(code, module.__dict__)
+            exec(self.code, module.__dict__)
 
 
     class JarImportFinder:
         def __init__(self):
-            self.namelist_cache = {}
+            self.zipimport = __import__("zipimport")
 
         def find_spec(self, fullname, path, target=None):
             for path in sys.path:
                 if ".jar!" in path:
-                    jarfile, _, zippath = path.partition("!")
-                    file_to_find = "%s/%s.py" % (zippath, fullname.replace(".", "/"))
-                    init_to_find = "%s/%s/__init__.py" % (zippath, fullname.replace(".", "/"))
-                    old_mtime, namelist = self.namelist_cache.get(jarfile, (None, None))
-                    try:
-                        mtime = posix.stat(jarfile).st_mtime
-                    except OSError:
-                        mtime = -1
-                    if namelist is None or mtime > old_mtime:
-                        import zipfile
-                        with zipfile.ZipFile(jarfile) as z:
-                            namelist = z.namelist()
-                            self.namelist_cache[jarfile] = (mtime, namelist)
-                    if file_to_find in namelist:
-                        return _frozen_importlib.ModuleSpec(fullname, JarImportLoader(jarfile, file_to_find), is_package=False)
-                    elif init_to_find in namelist:
-                        return _frozen_importlib.ModuleSpec(fullname, JarImportLoader(jarfile, init_to_find), is_package=True)
+                    zipimport_path = path.replace(".jar!/", ".jar/").replace(".jar!", ".jar/")
+                    zipimporter = self.zipimport.zipimporter(zipimport_path)
+                    if zipimporter.find_module(fullname):
+                        if zipimporter.is_package(fullname):
+                            return _frozen_importlib.ModuleSpec(fullname, JarImportLoader(zipimporter.get_code(fullname)), is_package=True)
+                        else:
+                            return _frozen_importlib.ModuleSpec(fullname, JarImportLoader(zipimporter.get_code(fullname)), is_package=False)
 
 
     sys.meta_path.append(JarImportFinder())