gen_java.py

import sys, re, os.path
from string import Template

try:
    from cStringIO import StringIO
except:
    from StringIO import StringIO

ctype2j = {
    # c       : (j, jn, jni, jni code)
    ""        : ("", "long", "jlong", ""), # c-tor
    "void"    : ("void", "void", "void", ""),
    "bool"    : ("boolean", "boolean","jboolean", "Z"),
    "int"     : ("int", "int", "jint", "I"),
    "long"    : ("int", "int", "jint", "I"),
    "float"   : ("float", "float", "jfloat", "F"),
    "double"  : ("double", "double", "jdouble", "D"),
    "size_t"  : ("long", "long", "jlong", "J"),
    "env"     : ("", "", "JNIEnv*", ""), # dummy 'env'
    "cls"     : ("", "", "jclass", ""), # dummy 'cls'
#
    "Mat"     : ("Mat",  (("size_t", ".nativeObj"),), "*%(n)s", "J"),
    "Point"   : ("Point", (("double", ".x"), ("double", ".y")), "cv::Point((int)%(n)s_x, (int)%(n)s_y)", "DD"),
    "Point2f" : ("Point", (("double", ".x"), ("double", ".y")), "cv::Point2f((float)%(n)s_x, (float)%(n)s_y)", "DD"),
    "Point2d" : ("Point", (("double", ".x"), ("double", ".y")), "cv::Point2d(%(n)s_x, %(n)s_y)", "DD"),
    "Point3i" : ("Point", (("double", ".x"), ("double", ".y"), ("double", ".z")),\
                            "cv::Point3i((int)%(n)s_x, (int)%(n)s_y, (int)%(n)s_z)", "DDD"),
    "Point3f" : ("Point", (("double", ".x"), ("double", ".y"), ("double", ".z")),\
                            "cv::Point3f((float)%(n)s_x, (float)%(n)s_y, (float)%(n)s_z)", "DDD"),
    "Point3d" : ("Point", (("double", ".x"), ("double", ".y"), ("double", ".z")),\
                            "cv::Point3d(%(n)s_x, %(n)s_y, %(n)s_z)", "DDD"),
    "Rect"    : ("Rect",  (("int", ".x"), ("int", ".y"), ("int", ".width"), ("int", ".height")), \
                            "cv::Rect(%(n)s_x, %(n)s_y, %(n)s_width, %(n)s_height)", "IIII"),
    "Size"    : ("Size",  (("int", ".width"), ("int", ".height")), "cv::Size(%(n)s_width, %(n)s_height)", "II"),
    "Scalar"  : ("Scalar",  (("double", ".v0"), ("double", ".v1"), ("double", ".v2"), ("double", ".v3")),\
                             "cv::Scalar(%(n)s_v0, %(n)s_v1, %(n)s_v2, %(n)s_v3)", "DDDD"),

}

class ConstInfo(object):
    def __init__(self, cname, name, val):
##        self.name = re.sub(r"^cv\.", "", name).replace(".", "_")
        self.cname = cname
        self.name =  re.sub(r"^Cv", "", name)
        #self.name = re.sub(r"([a-z])([A-Z])", r"\1_\2", name)
        #self.name = self.name.upper()
        self.value = val


class ClassInfo(object):
    def __init__(self, decl): # [ 'class/struct cname', [bases], [modlist] ]
        name = decl[0]
        name = name[name.find(" ")+1:].strip()
        self.cname = self.name = self.jname = re.sub(r"^cv\.", "", name)
        self.cname =self.cname.replace(".", "::")
        self.jname =  re.sub(r"^Cv", "", self.jname)
        self.methods = {}
        self.consts = [] # using a list to save the occurence order
        for m in decl[2]:
            if m.startswith("="):
                self.jname = m[1:]


class ArgInfo(object):
    def __init__(self, arg_tuple): # [ ctype, name, def val, [mod], argno ]
        self.ctype = arg_tuple[0]
        self.name = arg_tuple[1]
        self.defval = arg_tuple[2]
        self.out = "/O" in arg_tuple[3] or "/IO" in arg_tuple[3]

##    def isbig(self):
##        return self.ctype == "Mat" or self.ctype == "vector_Mat"


class FuncInfo(object):
    def __init__(self, decl): # [ funcname, return_ctype, [modifiers], [args] ]
        name = re.sub(r"^cv\.", "", decl[0])
        self.cname = name.replace(".", "::")
        classname = ""
        dpos = name.rfind(".")
        if dpos >= 0:
            classname = name[:dpos]
            name = name[dpos+1:]
        self.classname = classname
        self.jname = self.name = name
        if "[" in name:
            self.jname = "getelem"
        for m in decl[2]:
            if m.startswith("="):
                self.jname = m[1:]
        self.jn_name = "n_" + self.jname
        self.jni_name= re.sub(r"_", "_1", self.jn_name)
        if self.classname:
            self.jni_name = "00024" + self.classname + "_" + self.jni_name
        self.static = ["","static"][ "/S" in decl[2] ]
        self.ctype = decl[1] or ""
        self.args = []
        self.jni_suffix = "__"
        if self.classname and self.ctype and not self.static: # non-static class methods except c-tors
            self.jni_suffix += "J" # artifical 'self'
        for a in decl[3]:
            ai = ArgInfo(a)
            self.args.append(ai)
            self.jni_suffix += ctype2j.get(ai.ctype, ["","","",""])[3]



class FuncFamilyInfo(object):
    def __init__(self, decl): # [ funcname, return_ctype, [modifiers], [args] ]
        self.funcs = []
        self.funcs.append( FuncInfo(decl) )
        self.jname = self.funcs[0].jname
        self.isconstructor = self.funcs[0].name == self.funcs[0].classname



    def add_func(self, fi):
        self.funcs.append( fi )


class JavaWrapperGenerator(object):
    def __init__(self):
        self.clear()

    def clear(self):
        self.classes = { "Mat" : ClassInfo([ 'class Mat', [], [] ]) }
        self.funcs = {}
        self.consts = [] # using a list to save the occurence order
        self.module = ""
        self.java_code = StringIO()
        self.cpp_code = StringIO()
        self.ported_func_counter = 0
        self.func_counter = 0

    def add_class(self, decl):
        classinfo = ClassInfo(decl)
        if classinfo.name in self.classes:
            print "Generator error: class %s (%s) is duplicated" % \
                    (classinfo.name, classinfo.cname)
            sys.exit(-1)
        self.classes[classinfo.name] = classinfo
        if classinfo.name in ctype2j:
            print "Duplicated class: " + classinfo.name
            sys.exit(-1)
        ctype2j[classinfo.name] = (classinfo.jname, (("size_t", ".nativeObj"),), "*%(n)s", "J")


    def add_const(self, decl): # [ "const cname", val, [], [] ]
        consts = self.consts
        name = decl[0].replace("const ", "").strip()
        name = re.sub(r"^cv\.", "", name)
        cname = name.replace(".", "::")
        # check if it's a class member
        dpos = name.rfind(".")
        if dpos >= 0:
            classname = name[:dpos]
            name = name[dpos+1:]
            if classname in self.classes:
                consts = self.classes[classname].consts
            else:
                # this class isn't wrapped
                # skipping this const
                return
        constinfo = ConstInfo(cname, name, decl[1])
        # checking duplication
        for c in consts:
            if c.name == constinfo.name:
                print "Generator error: constant %s (%s) is duplicated" \
                        % (constinfo.name, constinfo.cname)
                sys.exit(-1)
        consts.append(constinfo)

    def add_func(self, decl):
        ffi = FuncFamilyInfo(decl)
        func_map = self.funcs
        classname = ffi.funcs[0].classname
        if classname:
            if classname in self.classes:
                func_map = self.classes[classname].methods
            else:
                print "Generator error: the class %s for method %s is missing" % \
                        (classname, ffi.jname)
                sys.exit(-1)
        if ffi.jname in func_map:
            func_map[ffi.jname].add_func(ffi.funcs[0])
        else:
            func_map[ffi.jname] = ffi

    def save(self, path, name, buf):
        f = open(path + "/" + name, "wt")
        f.write(buf.getvalue())
        f.close()

    def gen(self, srcfiles, module, output_path):
        self.clear()
        self.module = module
        parser = hdr_parser.CppHeaderParser()

        # step 1: scan the headers and build more descriptive maps of classes, consts, functions
        for hdr in srcfiles:
            decls = parser.parse(hdr)
            for decl in decls:
                name = decl[0]
                if name.startswith("struct") or name.startswith("class"):
                    self.add_class(decl)
                    pass
                elif name.startswith("const"):
                    self.add_const(decl)
                else: # function
                    self.add_func(decl)
                    pass

        # java module header
        self.java_code.write(\
"""package org.opencv;

public class %(module)s {

	//Load the native jni library
	static {
		System.loadLibrary("opencv_java");
	}

    public static final int
            CV_8U  = 0,
            CV_8S  = 1,
            CV_16U = 2,
            CV_16S = 3,
            CV_32S = 4,
            CV_32F = 5,
            CV_64F = 6,
            CV_USRTYPE1 = 7,
            IPL_BORDER_CONSTANT = 0,
            IPL_BORDER_REPLICATE = 1,
            IPL_BORDER_REFLECT = 2,
            IPL_BORDER_WRAP = 3,
            IPL_BORDER_REFLECT_101 = 4,
            IPL_BORDER_TRANSPARENT = 5;
""" % {"module" : module} )

        # cpp module header
        self.cpp_code.write(\
"""// This file is auto-generated, please don't edit!

#include <jni.h>

""" % {"module" : module})
        self.cpp_code.write( "\n".join(['#include "opencv2/%s/%s"' % (module, os.path.basename(f)) \
                            for f in srcfiles]) )
        self.cpp_code.write("\n\n")

        # step 2: generate the code for global constants
        self.gen_consts()

        # step 3: generate the code for all the global functions
        self.gen_funcs()

        # step 4: generate code for the classes
        #self.gen_classes() # !!! tempory disabled !!!

        # java module tail
        self.java_code.write("}\n")

        self.save(output_path, module+".java", self.java_code)
        self.save(output_path, module+".cpp",  self.cpp_code)

        print "Done %i of %i funcs." % (self.ported_func_counter, self.func_counter)


    def gen_consts(self):
        # generate the code for global constants
        if self.consts:
            self.java_code.write("""
    public static final int
            """ + """,
            """.join(["%s = %s" % (c.name, c.value) for c in self.consts]) + \
            ";\n\n")


    def gen_func(self, fi, isoverload):
        self.func_counter += 1

        # java part & cpp part:
        # // c_decl
        # e.g:
        # //  void add(Mat src1, Mat src2, Mat dst, Mat mask = Mat(), int dtype = -1)
        c_decl = "%s %s %s(%s)" % \
            ( fi.static, fi.ctype, fi.cname, \
              ", ".join(a.ctype + " " + a.name + [""," = "+a.defval][bool(a.defval)] for a in fi.args) )
        indent = ""
        if fi.classname:
            indent = " " * 4
        self.java_code.write( "\n    %s// %s\n" % (indent, c_decl) )
        self.cpp_code.write( "\n//\n//%s\n//\n" % c_decl )
        # check if we 'know' all the types
        if fi.ctype and fi.ctype!="Mat" and fi.ctype[0].isupper(): # ret val is class, NYI (TODO!)
            self.java_code.write( "    %s// Return type '%s' is not yet supported, skipping the function\n\n"\
                                  % (indent, fi.ctype) )
            print "SKIP:", c_decl, "\n\tdue to RET type", fi.ctype
            return
        types = [fi.ctype]
        types.extend([a.ctype for a in fi.args])
        for t in types:
            if t not in ctype2j:
                self.java_code.write( "    %s// Unknown type '%s', skipping the function\n\n" % (indent, t) )
                print "SKIP:", c_decl, "\n\tdue to ARG type", t
                return
        for a in fi.args:
            if a.ctype[0].isupper() and a.ctype != "Mat" and a.out: # C++ reference to a class (gcc disallows temp obj reference)
                self.java_code.write( "    %s// Unknown type '%s&', skipping the function\n\n" % (indent, t) )
                print "SKIP:", c_decl, "\n\tdue to ARG type", a.ctype + "&"
                return
        if fi.cname == "minEnclosingCircle":
                self.java_code.write( "    %s// Temporary skipping the function %s\n\n" % (indent, fi.cname) )
                print "SKIP:", c_decl, "\n\tdue to Temporary filtering"
                return

        self.ported_func_counter += 1
        # java args
        args = fi.args[:]
        if args and args[-1].defval:
            isoverload = True
        suffix = fi.jni_suffix

        while True:

            # java native method args
            jn_args = []
            if fi.classname and fi.ctype and not fi.static: # non-static class method except c-tor
                jn_args.append(ArgInfo([ "size_t", "nativeObj", "", [], "" ])) # adding 'this'
            for a in args:
                if a.ctype[0].isupper(): # Point/Rect/...
                    #"Point" : ("Point", [["int", ".x"], ["int", ".y"]], ...)
                    fields = ctype2j[a.ctype][1]
                    for f in fields:
                        jn_args.append( ArgInfo([ f[0], a.name + f[1], "", [], "" ]) )
                else:
                    jn_args.append(a)

            # jni (cpp) function args
            jni_args = [ArgInfo([ "env", "env", "", [], "" ]), ArgInfo([ "cls", "cls", "", [], "" ])]
            if fi.classname and fi.ctype and not fi.static:
                jni_args.append(ArgInfo([ "size_t", "self", "", [], "" ]))
            for a in args:
                if a.ctype[0].isupper(): # Point/Rect/...
                    #"Point" : ("Point", [["int", ".x"], ["int", ".y"]], ...)
                    fields = ctype2j[a.ctype][1]
                    for f in fields:
                        jni_args.append( ArgInfo([ f[0], a.name + f[1].replace(".","_"), "", [], "" ]) )
                else:
                    jni_args.append(a)

            # java part:
            # private java NATIVE method decl
            # e.g.
            # private static native void n_add(long src1, long src2, long dst, long mask, int dtype);
            jn_type = ""
            if fi.ctype == "Mat":
                jn_type = "long"
            elif fi.ctype[0].isupper():
                jn_type = "NYI" # TODO: NYI
            else:
                jn_type = ctype2j[fi.ctype][1]

            self.java_code.write( Template(\
                "    ${indent}private static native $jn_type $jn_name($jn_args);\n").substitute(\
                indent = indent, \
                jn_type=jn_type, \
                jn_name=fi.jn_name, \
                jn_args=", ".join(["%s %s" % (ctype2j[a.ctype][1], a.name.replace(".","_")) for a in jn_args])
            ) );

            # java part:
            # public java wrapper method impl (calling native one above)
            # e.g.
            # public static void add( Mat src1, Mat src2, Mat dst, Mat mask, int dtype )
            # { n_add( src1.nativeObj, src2.nativeObj, dst.nativeObj, mask.nativeObj, dtype );  }
            impl_code = " return $jn_name($jn_args_call); "
            if fi.ctype == "void":
                impl_code = " $jn_name($jn_args_call); "
            elif fi.ctype == "": # c-tor
                impl_code = " nativeObj = $jn_name($jn_args_call); "
            elif fi.ctype in self.classes: # wrapped class
                impl_code = " return new %s( $jn_name($jn_args_call) ); " % \
                    self.classes[fi.ctype].jname

            static = "static"
            if fi.classname:
                static = fi.static

            self.java_code.write( Template(\
                "    ${indent}public $static $j_type $j_name($j_args)").substitute(\
                indent = indent, \
                static=static, \
                j_type=ctype2j[fi.ctype][0], \
                j_name=fi.jname, \
                j_args=", ".join(["%s %s" % (ctype2j[a.ctype][0], a.name) for a in args]) \
            ) )

            self.java_code.write( Template("\n    $indent{ " + impl_code + " }\n").substitute(\
                indent = indent, \
                jn_name=fi.jn_name, \
                jn_args_call=", ".join([a.name + ["",".nativeObj"][ctype2j[a.ctype][0]=="Mat"] for a in jn_args])\
            ) )

            # cpp part:
            # jni_func(..) { return cv_func(..); }
            ret = "return "
            if fi.ctype == "void":
                ret = ""
            elif fi.ctype == "Mat":
                ret = "return (jlong) new cv::Mat"
            elif fi.ctype[0].isupper():
                ret = NYI # NYI

            cvname = "cv::" + fi.name
            j2cvargs = []
            if fi.classname:
                if not fi.ctype: # c-tor
                    cvname = "(jlong) new cv::" + fi.classname
                elif fi.static:
                    cvname = "cv::%s::%s" % (fi.classname, fi.name)
                else:
                    cvname = "%s->%s" % ("me", fi.name)
                    j2cvargs.append(\
                        "cv::%s* me = (cv::%s*) self; //TODO: check for NULL" % \
                            (fi.classname, fi.classname) \
                    )
            cvargs = []
            for a in args:
                cva = a.name
                if a.ctype[0].isupper(): # Point/Rect/...
                    # "Point" : ("Point", (("int", ".x"), ("int", ".y")), "Point(%(n)s_x, %(n)s_y)", "II")
                    # Point(p_x, p_y)
                    cva = ctype2j[a.ctype][2] % {"n" : a.name}
                    if a.ctype == "Mat":
                        j2cvargs.append("cv::Mat* %s = (cv::Mat*) %s_nativeObj; //TODO: check for NULL"\
                                        % (a.name, a.name))
                    pass
                cvargs.append(cva)

            rtype = "NYI"
            if fi.ctype == "Mat":
                rtype = "jlong"
            elif fi.ctype[0].isupper():
                rtype = "NYI" # TODO: NYI
            else:
                rtype = ctype2j[fi.ctype][2]

            self.cpp_code.write ( Template( \
"""
#ifdef __cplusplus
extern "C" {
#endif

JNIEXPORT $rtype JNICALL Java_org_opencv_${module}_$fname
  ($args);

#ifdef __cplusplus
}
#endif

JNIEXPORT $rtype JNICALL Java_org_opencv_${module}_$fname
  ($args)
{
    $j2cv
    $ret( $cvname( $cvargs ) );
}

""" ).substitute( \
        rtype = rtype, \
        module = self.module, \
        fname = fi.jni_name + ["",suffix][isoverload], \
        args = ", ".join(["%s %s" % (ctype2j[a.ctype][2], a.name) for a in jni_args]), \
        j2cv = "\n    ".join([a for a in j2cvargs]), \
        ret = ret, \
        cvname = cvname, \
        cvargs = ", ".join([a for a in cvargs]), \
    ) )

            # processing args with default values
            if args and args[-1].defval:
                a = args.pop()
                suffix = suffix[0:-len(ctype2j[a.ctype][3])]
            else:
                break



    def gen_funcs(self):
        # generate the code for all the global functions
        indent = "\t"
        fflist = self.funcs.items()
        fflist.sort()
        for name, ffi in fflist:
            assert not ffi.funcs[0].classname, "Error: global func is a class member - "+name
            for fi in ffi.funcs:
                self.gen_func(fi, len(ffi.funcs)>1)


    def gen_classes(self):
        # generate code for the classes (their methods and consts)
        indent = "\t"
        indent_m = indent + "\t"
        classlist = self.classes.items()
        classlist.sort()
        for name, ci in classlist:
            self.java_code.write( "\n" + indent + "// class %s" % (ci.cname) + "\n" )
            self.java_code.write( indent + "public static class %s {\n\n" % (ci.jname) )

            # self
            self.java_code.write( indent_m + "protected final long nativeObj;\n" )
            self.java_code.write( indent_m + "protected %s(long addr) { nativeObj = addr; }\n\n" \
                % name );
            # constants
            if ci.consts:
                prefix = "\n" + indent_m + "\t\t"
                s = indent_m + "public static final int" + prefix +\
                    ("," + prefix).join(["%s = %s" % (c.name, c.value) for c in ci.consts]) + ";\n\n"
                self.java_code.write( s )
            # c-tors
            fflist = ci.methods.items()
            fflist.sort()
            for n, ffi in fflist:
                if ffi.isconstructor:
                    for fi in ffi.funcs:
                        self.gen_func(fi, len(ffi.funcs)>1)
            self.java_code.write( "\n" )
            for n, ffi in fflist:
                if not ffi.isconstructor:
                    for fi in ffi.funcs:
                        self.gen_func(fi, len(ffi.funcs)>1)

            self.java_code.write( "\n" + indent + "}\n\n" )


if __name__ == "__main__":
    if len(sys.argv) < 4:
        print "Usage:\n", \
            os.path.basename(sys.argv[0]), \
            "<full path to hdr_parser.py> <module name> <C++ header> [<C++ header>...]"
        print "Current args are: ", ", ".join(["'"+a+"'" for a in sys.argv])
        exit(0)

    dstdir = "."
    hdr_parser_path = os.path.abspath(sys.argv[1])
    if hdr_parser_path.endswith(".py"):
        hdr_parser_path = os.path.dirname(hdr_parser_path)
    sys.path.append(hdr_parser_path)
    import hdr_parser
    module = sys.argv[2]
    srcfiles = sys.argv[3:]
    print "Generating module '" + module + "' from headers:\n\t" + "\n\t".join(srcfiles)
    generator = JavaWrapperGenerator()
    generator.gen(srcfiles, module, dstdir)