jsj_javaclass.c

caffeine-monkey java实现的js模拟引擎

JS_STATIC_DLL_CALLBACK(JSBool)
JavaClass_deleteProperty(JSContext *cx, JSObject *obj, jsid id, jsval *vp)
{
    JSVersion version = JS_GetVersion(cx);
    
    *vp = JSVAL_FALSE;

    if (!JSVERSION_IS_ECMA(version)) {
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL,
                                            JSJMSG_JCLASS_PROP_DELETE);
        return JS_FALSE;
    } else {
        /* Attempts to delete permanent properties are silently ignored
           by ECMAScript. */
        return JS_TRUE;
    }
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaClass_defaultValue(JSContext *cx, JSObject *obj, JSType type, jsval *vp)
{
    /* printf("In JavaClass_defaultValue()\n"); */
    return JavaClass_convert(cx, obj, JSTYPE_STRING, vp);
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaClass_newEnumerate(JSContext *cx, JSObject *obj, JSIterateOp enum_op,
                       jsval *statep, jsid *idp)
{
    JavaMemberDescriptor *member_descriptor;
    JavaClassDescriptor *class_descriptor;
    JNIEnv *jEnv;
    JSJavaThreadState *jsj_env;
    
    class_descriptor = JS_GetPrivate(cx, obj);

    /* Check for prototype JavaClass object */
    if (!class_descriptor) {
        *statep = JSVAL_NULL;
        if (idp)
            *idp = INT_TO_JSVAL(0);
        return JS_TRUE;
    }
    
    switch(enum_op) {
    case JSENUMERATE_INIT:
        /* Get the Java per-thread environment pointer for this JSContext */
        jsj_env = jsj_EnterJava(cx, &jEnv);
        if (!jEnv)
            return JS_FALSE;
        member_descriptor = jsj_GetClassStaticMembers(cx, jEnv, class_descriptor);
        *statep = PRIVATE_TO_JSVAL(member_descriptor);
        if (idp)
            *idp = INT_TO_JSVAL(class_descriptor->num_instance_members);
	jsj_ExitJava(jsj_env);
        return JS_TRUE;
        
    case JSENUMERATE_NEXT:
        member_descriptor = JSVAL_TO_PRIVATE(*statep);
        if (member_descriptor) {

            /* Don't enumerate explicit-signature methods, i.e. enumerate toValue,
               but not toValue(int), toValue(double), etc. */
            while (member_descriptor->methods && member_descriptor->methods->is_alias) {
                member_descriptor = member_descriptor->next;
                if (!member_descriptor) {
                    *statep = JSVAL_NULL;
                    return JS_TRUE;
                }
            }

            *idp = member_descriptor->id;
            *statep = PRIVATE_TO_JSVAL(member_descriptor->next);
            return JS_TRUE;
        }
        /* Fall through ... */

    case JSENUMERATE_DESTROY:
        *statep = JSVAL_NULL;
        return JS_TRUE;

    default:
        JS_ASSERT(0);
        return JS_FALSE;
    }
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaClass_checkAccess(JSContext *cx, JSObject *obj, jsid id,
                      JSAccessMode mode, jsval *vp, uintN *attrsp)
{
    switch (mode) {
    case JSACC_WATCH:
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL, 
                                            JSJMSG_JCLASS_PROP_WATCH);
        return JS_FALSE;

    case JSACC_IMPORT:
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL, 
                                            JSJMSG_JCLASS_PROP_EXPORT);
        return JS_FALSE;

    default:
        return JS_TRUE;
    }
}

/*
 * Implement the JavaScript instanceof operator for JavaClass objects by using
 * the equivalent Java instanceof operation.
 */
JS_STATIC_DLL_CALLBACK(JSBool)
JavaClass_hasInstance(JSContext *cx, JSObject *obj, jsval candidate_jsval,
                      JSBool *has_instancep)
{
    JavaClassDescriptor *class_descriptor;
    JavaObjectWrapper *java_wrapper;
    JSClass *js_class;
    JSBool has_instance;
    JSObject *candidate_obj;
    jclass java_class;
    jobject java_obj;
    JNIEnv *jEnv;
    JSJavaThreadState *jsj_env;
    
    has_instance = JS_FALSE;
    class_descriptor = JS_GetPrivate(cx, obj);
    if (!class_descriptor) {
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL, 
                                                    JSJMSG_BAD_OP_JCLASS);
        return JS_FALSE;
    }

    /*
     * Make sure that the thing to the left of the instanceof operator is a
     * Java object.
     */
    if (!JSVAL_IS_OBJECT(candidate_jsval))
        goto done;
    candidate_obj = JSVAL_TO_OBJECT(candidate_jsval);
#ifdef JS_THREADSAFE
    js_class = JS_GetClass(cx, candidate_obj);
#else
    js_class = JS_GetClass(candidate_obj);
#endif
    if ((js_class != &JavaObject_class) && (js_class != &JavaArray_class))
        goto done;

    java_class = class_descriptor->java_class;
    java_wrapper = JS_GetPrivate(cx, candidate_obj);
    if (!java_wrapper) {
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL, 
                                                JSJMSG_BAD_OP_PROTO);
        return JS_FALSE;
    }
    java_obj = java_wrapper->java_obj;
    /* Get JNI pointer */
    jsj_env = jsj_EnterJava(cx, &jEnv);
    has_instance = (*jEnv)->IsInstanceOf(jEnv, java_obj, java_class);
    jsj_ExitJava(jsj_env);

done:
    *has_instancep = has_instance;
    return JS_TRUE;
}

JSObjectOps JavaClass_ops = {
    /* Mandatory non-null function pointer members. */
    jsj_wrapper_newObjectMap,       /* newObjectMap */
    jsj_wrapper_destroyObjectMap,   /* destroyObjectMap */
    JavaClass_lookupProperty,
    JavaClass_defineProperty,
    JavaClass_getPropertyById,      /* getProperty */
    JavaClass_setPropertyById,      /* setProperty */
    JavaClass_getAttributes,
    JavaClass_setAttributes,
    JavaClass_deleteProperty,
    JavaClass_defaultValue,
    JavaClass_newEnumerate,
    JavaClass_checkAccess,

    /* Optionally non-null members start here. */
    NULL,                           /* thisObject */
    NULL,                           /* dropProperty */
    jsj_JavaConstructorWrapper,     /* call */
    jsj_JavaConstructorWrapper,     /* construct */
    NULL,                           /* xdrObject */
    JavaClass_hasInstance,          /* hasInstance */
    NULL,                           /* setProto */
    NULL,                           /* setParent */
    NULL,                           /* mark */
    NULL,                           /* clear */
    jsj_wrapper_getRequiredSlot,    /* getRequiredSlot */
    jsj_wrapper_setRequiredSlot     /* setRequiredSlot */
};

JS_STATIC_DLL_CALLBACK(JSObjectOps *)
JavaClass_getObjectOps(JSContext *cx, JSClass *clazz)
{
    return &JavaClass_ops;
}

JSClass JavaClass_class = {
    "JavaClass", JSCLASS_HAS_PRIVATE,
    NULL, NULL, NULL, NULL,
    NULL, NULL, JavaClass_convert, JavaClass_finalize,

    /* Optionally non-null members start here. */
    JavaClass_getObjectOps,
    NULL,
    NULL,
    NULL,
    NULL,
    NULL,
    NULL,
    0,
};

static JSObject *
jsj_new_JavaClass(JSContext *cx, JNIEnv *jEnv, JSObject* parent_obj,
                  JavaClassDescriptor *class_descriptor)
{
    JSObject *JavaClass_obj;

    JavaClass_obj = JS_NewObject(cx, &JavaClass_class, 0, parent_obj);
    if (!JavaClass_obj)
        return NULL;

    JS_SetPrivate(cx, JavaClass_obj, (void *)class_descriptor);

#ifdef DEBUG
    /*    printf("JavaClass \'%s\' created\n", class_descriptor->name); */
#endif

    return JavaClass_obj;
}

JSObject *
jsj_define_JavaClass(JSContext *cx, JNIEnv *jEnv, JSObject* parent_obj,
                     const char *simple_class_name,
                     jclass java_class)
{
    JavaClassDescriptor *class_descriptor;
    JSObject *JavaClass_obj;

    class_descriptor = jsj_GetJavaClassDescriptor(cx, jEnv, java_class);
    if (!class_descriptor)
        return NULL;

    JavaClass_obj = jsj_new_JavaClass(cx, jEnv, parent_obj, class_descriptor);
    if (!JavaClass_obj)
        return NULL;

    if (!JS_DefineProperty(cx, parent_obj, simple_class_name,
                           OBJECT_TO_JSVAL(JavaClass_obj), 0, 0,
                           JSPROP_PERMANENT|JSPROP_READONLY|JSPROP_ENUMERATE))
        return NULL;
    return JavaClass_obj;
}


/*
 * The getClass() native JS method is defined as a property of the global
 * object.  Given a JavaObject it returns the corresponding JavaClass.  This
 * is useful for accessing static methods and fields.
 *
 *    js> getClass(new java.lang.String("foo"))
 *    [JavaClass java.lang.String]
 */
JS_STATIC_DLL_CALLBACK(JSBool)
getClass(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
    JSObject *obj_arg, *JavaClass_obj;
    JavaObjectWrapper *java_wrapper;
    JavaClassDescriptor *class_descriptor;
    JNIEnv *jEnv;
    JSJavaThreadState *jsj_env;

    if (argc != 1 ||
    !JSVAL_IS_OBJECT(argv[0]) ||
    !(obj_arg = JSVAL_TO_OBJECT(argv[0])) ||
    (!JS_InstanceOf(cx, obj_arg, &JavaObject_class, 0) &&
         !JS_InstanceOf(cx, obj_arg, &JavaArray_class, 0))) {
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL, 
                                                JSJMSG_NEED_JOBJECT_ARG);
        return JS_FALSE;
    }

    java_wrapper = JS_GetPrivate(cx, obj_arg);
    if (!java_wrapper) {
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL, 
                                                JSJMSG_PROTO_GETCLASS);
        return JS_FALSE;
    }

    jsj_env = jsj_EnterJava(cx, &jEnv);
    if (!jEnv)
        return JS_FALSE;
    
    class_descriptor = java_wrapper->class_descriptor;

    JavaClass_obj = jsj_new_JavaClass(cx, jEnv, NULL, class_descriptor);
    if (!JavaClass_obj) {
	jsj_ExitJava(jsj_env);
        return JS_FALSE;
    }

    *rval = OBJECT_TO_JSVAL(JavaClass_obj);
    jsj_ExitJava(jsj_env);
    return JS_TRUE;
}

JS_STATIC_DLL_CALLBACK(JSBool)
JavaClass_construct(JSContext *cx, JSObject *obj, uintN argc, jsval *argv, jsval *rval)
{
    JSObject *obj_arg, *JavaClass_obj;
    JavaObjectWrapper *java_wrapper;
    JavaClassDescriptor *class_descriptor;
    JNIEnv *jEnv;
    JSJavaThreadState *jsj_env;

    if (argc != 1 ||
	!JSVAL_IS_OBJECT(argv[0]) ||
	!(obj_arg = JSVAL_TO_OBJECT(argv[0])) ||
	!JS_InstanceOf(cx, obj_arg, &JavaObject_class, 0) ||
	((java_wrapper = JS_GetPrivate(cx, obj_arg)) == NULL)) {
        JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL, 
                             JSJMSG_NEED_JCLASS_ARG);
        return JS_FALSE;
    }

    jsj_env = jsj_EnterJava(cx, &jEnv);
    if (!jEnv)
        return JS_FALSE;

    class_descriptor = java_wrapper->class_descriptor;
    if (!(*jEnv)->IsSameObject(jEnv, class_descriptor->java_class, jlClass)) {
	JS_ReportErrorNumber(cx, jsj_GetErrorMessage, NULL, 
                             JSJMSG_NEED_JCLASS_ARG);
	jsj_ExitJava(jsj_env);
        return JS_FALSE;
    }

    class_descriptor = jsj_GetJavaClassDescriptor(cx, jEnv, java_wrapper->java_obj);
    JavaClass_obj = jsj_new_JavaClass(cx, jEnv, NULL, class_descriptor);
    if (!JavaClass_obj) {
	jsj_ExitJava(jsj_env);
        return JS_FALSE;
    }

    *rval = OBJECT_TO_JSVAL(JavaClass_obj);
    jsj_ExitJava(jsj_env);
    return JS_TRUE;
}

extern JS_IMPORT_DATA(JSObjectOps) js_ObjectOps;

JSBool
jsj_init_JavaClass(JSContext *cx, JSObject *global_obj)
{
    /* Define JavaClass class */
    if (!JS_InitClass(cx, global_obj, 0, &JavaClass_class, JavaClass_construct, 0, 0, 0, 0, 0))
        return JS_FALSE;

    if (!JS_DefineFunction(cx, global_obj, "getClass", getClass, 0,
                           JSPROP_READONLY))
        return JS_FALSE;

    return jsj_InitJavaClassReflectionsTable();
}