Deprecate java.generate_native_header() in favor of java.generate_native_headers()

After implementing a much more extensive Java native module than what
currently exists in the tests, I found shortcomings.

1. You need to be able to pass multiple Java files.
2. Meson needs more information to better track the generated native
   headers.
3. Meson wasn't tracking the header files generated from inner classes.

This new function should fix all the issues the old function had with
room to grow should more functionality need to be added. What I
implemented here in this new function is essentially what I have done in
the Heterogeneous-Memory Storage Engine's Java bindings.

1 files changed, 44 insertions, 3 deletions

diff --git a/mesonbuild/modules/java.py b/mesonbuild/modules/java.py
index 20cf3fd..dc660a7 100644
--- a/mesonbuild/modules/java.py
+++ b/mesonbuild/modules/java.py
@@ -15,9 +15,10 @@
 import os
 import pathlib
 import typing as T
+from mesonbuild import mesonlib
 from mesonbuild.build import CustomTarget
 from mesonbuild.compilers import detect_compiler_for
-from mesonbuild.interpreterbase.decorators import FeatureNew, KwargInfo, typed_pos_args, typed_kwargs
+from mesonbuild.interpreterbase.decorators import ContainerTypeInfo, FeatureDeprecated, FeatureNew, KwargInfo, typed_pos_args, typed_kwargs
 from mesonbuild.interpreter.interpreterobjects import FileHolder
 from mesonbuild.mesonlib import version_compare, MachineChoice
 from . import ExtensionModule, ModuleReturnValue, ModuleState
@@ -29,18 +30,18 @@ class JavaModule(ExtensionModule):
         super().__init__(interpreter)
         self.methods.update({
             'generate_native_header': self.generate_native_header,
+            'generate_native_headers': self.generate_native_headers,
         })
 
         if 'java' not in interpreter.environment.coredata.compilers[MachineChoice.BUILD]:
             detect_compiler_for(interpreter.environment, 'java', MachineChoice.BUILD)
         self.javac = interpreter.environment.coredata.compilers[MachineChoice.BUILD]['java']
 
+    @FeatureDeprecated('java.generate_native_header', '0.62.0', 'Use java.generate_native_headers instead')
     @typed_pos_args('generate_native_header', (str, FileHolder))
     @typed_kwargs('java.generate_native_header', KwargInfo('package', str, default=None))
     def generate_native_header(self, state: ModuleState, args: T.Tuple[T.Union[str, FileHolder]],
                                kwargs: T.Dict[str, T.Optional[str]]) -> ModuleReturnValue:
-        assert state.backend
-
         package = kwargs.get('package')
 
         file = self.interpreter.source_strings_to_files(
@@ -74,5 +75,45 @@ class JavaModule(ExtensionModule):
 
         return ModuleReturnValue(target, [target])
 
+    @FeatureNew('java.generate_native_headers', '0.62.0')
+    @typed_pos_args('generate_native_headers', (str, mesonlib.File), min_varargs=1)
+    @typed_kwargs('java.generate_native_headers',
+        KwargInfo('classes', (ContainerTypeInfo(list, str)), default=[], listify=True,
+            required=True),
+        KwargInfo('package', str, default=None))
+    def generate_native_headers(self, state: ModuleState, args: T.List[mesonlib.FileOrString],
+                               kwargs: T.Dict[str, T.Optional[str]]) -> ModuleReturnValue:
+        classes = T.cast(T.List[str], kwargs.get('classes'))
+        package = kwargs.get('package')
+
+        headers: T.List[str] = []
+        for clazz in classes:
+            underscore_clazz = clazz.replace(".", "_")
+            if package:
+                headers.append(f'{package.replace(".", "_")}_{underscore_clazz}.h')
+            else:
+                headers.append(f'{underscore_clazz}.h')
+
+        command = mesonlib.listify([
+            self.javac.exelist,
+            '-d',
+            '@PRIVATE_DIR@',
+            '-h',
+            state.subdir,
+            '@INPUT@',
+        ])
+
+        prefix = classes[0] if not package else package
+
+        target = CustomTarget(f'{prefix}-native-headers', state.subdir, state.subproject, command,
+                              sources=list(args), outputs=headers, backend=state.backend)
+
+        # It is only known that 1.8.0 won't pre-create the directory. 11 and 16
+        # do not exhibit this behavior.
+        if version_compare(self.javac.version, '1.8.0'):
+            pathlib.Path(state.backend.get_target_private_dir_abs(target)).mkdir(parents=True, exist_ok=True)
+
+        return ModuleReturnValue(target, [target])
+
 def initialize(*args: T.Any, **kwargs: T.Any) -> JavaModule:
     return JavaModule(*args, **kwargs)