java: implement java linking

mesonbuild/backend/ninjabackend.py

@@ -970,7 +970,7 @@ int dummy;
         class_list = []
         compiler = target.compilers['java']
         c = 'c'
-        m = ''
+        m = 'm'
         e = ''
         f = 'f'
         main_class = target.get_main_class()
@@ -980,11 +980,21 @@ int dummy;
             plain_class_path = self.generate_single_java_compile(src, target, compiler, outfile)
             class_list.append(plain_class_path)
         class_dep_list = [os.path.join(self.get_target_private_dir(target), i) for i in class_list]
+        manifest_path = os.path.join(self.get_target_private_dir(target), 'Manifest.txt')
+        os.makedirs(os.path.dirname(os.path.join(self.environment.get_build_dir(), manifest_path)), exist_ok=True)
+        with open(manifest_path, 'w') as manifest:
+            if any(target.link_targets):
+                manifest.write('Class-Path: ')
+                cp_paths = [os.path.join(self.get_target_dir(l), l.get_filename()) for l in target.link_targets]
+                manifest.write(' '.join(cp_paths))
+            manifest.write('\n')
         jar_rule = 'java_LINKER'
         commands = [c + m + e + f]
+        commands.append(manifest_path)
         if e != '':
             commands.append(main_class)
         commands.append(self.get_target_filename(target))
+        commands.append(manifest_path)
         # Java compilation can produce an arbitrary number of output
         # class files for a single source file. Thus tell jar to just
         # grab everything in the final package.
@@ -1063,12 +1073,14 @@ int dummy;
         self.generate_generator_list_rules(target, outfile)
 
     def generate_single_java_compile(self, src, target, compiler, outfile):
+        deps = [os.path.join(self.get_target_dir(l), l.get_filename()) for l in target.link_targets]
         args = []
         args += compiler.get_buildtype_args(self.get_option_for_target('buildtype', target))
         args += self.build.get_global_args(compiler)
         args += self.build.get_project_args(compiler, target.subproject)
         args += target.get_java_args()
         args += compiler.get_output_args(self.get_target_private_dir(target))
+        args += target.get_classpath_args()
         curdir = target.get_subdir()
         sourcepath = os.path.join(self.build_to_src, curdir) + os.pathsep
         sourcepath += os.path.normpath(curdir) + os.pathsep
@@ -1080,6 +1092,7 @@ int dummy;
         plain_class_path = src.fname[:-4] + 'class'
         rel_obj = os.path.join(self.get_target_private_dir(target), plain_class_path)
         element = NinjaBuildElement(self.all_outputs, rel_obj, compiler.get_language() + '_COMPILER', rel_src)
+        element.add_dep(deps)
         element.add_item('ARGS', args)
         element.write(outfile)
         return plain_class_path

mesonbuild/build.py

@@ -1911,6 +1911,9 @@ class Jar(BuildTarget):
         for s in self.sources:
             if not s.endswith('.java'):
                 raise InvalidArguments('Jar source %s is not a java file.' % s)
+        for t in self.link_targets:
+            if not isinstance(t, Jar):
+                raise InvalidArguments('Link target %s is not a jar target.' % t)
         self.filename = self.name + '.jar'
         self.outputs = [self.filename]
         self.java_args = kwargs.get('java_args', [])
@@ -1928,6 +1931,13 @@ class Jar(BuildTarget):
         # All jar targets are installable.
         pass
 
+    def is_linkable_target(self):
+        return True
+
+    def get_classpath_args(self):
+        cp_paths = [os.path.join(l.get_subdir(), l.get_filename()) for l in self.link_targets]
+        return ['-cp', os.pathsep.join(cp_paths)]
+
 class CustomTargetIndex:
 
     """A special opaque object returned by indexing a CustomTarget. This object
@@ -1950,7 +1960,6 @@ class CustomTargetIndex:
     def get_subdir(self):
         return self.target.get_subdir()
 
-
 class ConfigureFile:
 
     def __init__(self, subdir, sourcename, targetname, configuration_data):