dxobject.c

用Java写的面相对象的数据库管理系统

/*
 $Id: DxObject.c,v 1.1 1999/10/04 13:26:24 daniela Exp $ 
 implemtation der native methode DxObject.invokeMethod()
*/

#include "DbxLib_DbxObject.h"
#include <javaString.h>
#include <interpreter.h>
#include <string.h>

char* signature (struct HDbxLib_DbxObject* this_h, char* method_name);
int is_end_string (char* str1, char* str2);

struct Hjava_lang_Object*
DbxLib_DbxObject_invoke(struct HDbxLib_DbxObject* this_h,
                        struct Hjava_lang_String* method_name_h,
                        long argNum,
                        struct Hjava_lang_Object* arg1_h,
                        struct Hjava_lang_Object* arg2_h,
                        struct Hjava_lang_Object* arg3_h)
   {
   ExecEnv* ee = EE();
   ClassDbxLib_DbxObject* this = unhand (this_h);
   char* method_name = makeCString (method_name_h);
   char* sig = signature (this_h, method_name);
   HObject* ans = NULL;
   
   /*konnte signatur fuer methode ermittelt werden? */
   if (sig == NULL) {
      SignalError (ee, "DbxLib/MethodNotFoundExc", NULL);
      return NULL;
      }
   
   switch (argNum) {
      case 0:	ans = (HObject*)execute_java_dynamic_method (ee, (HObject*)this_h, method_name, sig);
                break;    
      case 1:	ans = (HObject*)execute_java_dynamic_method (ee, (HObject*)this_h, method_name, sig, arg1_h);
                break;    
      case 2:	ans = (HObject*)execute_java_dynamic_method (ee, (HObject*)this_h, method_name, sig, arg1_h, arg2_h);
                break;    
      case 3:	ans = (HObject*)execute_java_dynamic_method (ee, (HObject*)this_h, method_name, sig, arg1_h, arg2_h, arg3_h);
                break;
      }            
   if (exceptionOccurred(ee)) {
      SignalError (ee, "DbxLib/MethodInvokeExc", NULL);
      return NULL;
      }
   return ans;
   }


/*
 Achtung: sig11, wenn methode nicht existiert!
*/
char* signature (struct HDbxLib_DbxObject* this_h, char* method_name)
   {
   struct methodtable* mtable = this_h->methods;
  // int method_num = mtable->classdescriptor->methods_count;
   char name[256];
   int i = 0;
   
   mangleMethodName (mtable->methods[++i], name, 256, NULL);

   while (!strstr(name, method_name))
      mangleMethodName (mtable->methods[++i], name, 256, NULL);

   return mtable->methods[i]->fb.signature;
   }
   
/*
 true, wenn str1 mit str2 abschliesst
*/
int is_end_string (char* str1, char* str2)
   {
   int pos1 = strlen (str1) - 1;
   int pos2 = strlen (str2) - 1;
   
   if (pos2 > pos1)
      return 0;
      
   while (pos2 >= 0) {
      if (str1[pos1--] != str2[pos2--])
         return 0;
      }
   return 0;      
   }