javaw: add possibility to enable recurse use also globally via env variable

playground/java_recursive_use/wscript

@@ -10,13 +10,16 @@
 # a project with many java artifacts and complex dependencies a manual
 # management may be expensive.
 #
-# By setting recurse_use to True the recursive behaviour is enabled.
+# By setting recurse_use to True (or build wise by setting RECURSE_JAVA env
+# variable to True) the recursive behaviour is enabled.
 #
 # Directory d tests the case when recursion stops earlier since
 # a dependency is already explicitly defined
 
 def configure(conf):
 	conf.load('java')
+	# For build wide enabling:
+	# conf.env.RECURSE_JAVA = True
 
 def build(bld):
 	bld.recurse('a b c d')

waflib/Tools/javaw.py

@@ -99,9 +99,14 @@ and then NNN can be freely used in rules as:
 
 In the java tool the dependencies via use are not transitive by default, as
 this necessity depends on the code. To enable recursive dependency scanning
-use:
+use on a specific rule:
+
 		recurse_use = True
 
+Or build wise by setting the RECURSE_JAVA environment variable to True:
+
+		bld.env.RECURSE_JAVA = True
+
 Unit tests can be integrated in the waf unit test environment using the
 javatest extra.
 
@@ -240,8 +245,8 @@ def use_javac_files(self):
 				for tsk in y.tasks:
 					self.javac_task.set_run_after(tsk)
 
-		# If recurse_use then recursively add use attribute for each used one
+		# If recurse use scan is enabled recursively add use attribute for each used one
-		if getattr(self, 'recurse_use', False):
+		if getattr(self, 'recurse_use', False) or self.bld.env.RECURSE_JAVA:
 			self.java_use_rec(x)
 
 	self.env.append_value('CLASSPATH', self.use_lst)