PrevNextExample

    // ------------------------------- //
    // -------- Start of File -------- //
    // ------------------------------- //
    // ----------------------------------------------------------- //
    // C++ Source Code File Name: testprog.cpp
    // Compiler Used: MSVC, BCC32, GCC, HPUX aCC, SOLARIS CC
    // Produced By: DataReel Software Development Team
    // File Creation Date: 02/04/1997
    // Date Last Modified: 06/17/2016
    // Copyright (c) 2001-2016 DataReel Software Development
    // ----------------------------------------------------------- //
    // ------------- Program Description and Details ------------- //
    // ----------------------------------------------------------- //
    /*
    This library is free software; you can redistribute it and/or
    modify it under the terms of the GNU Lesser General Public
    License as published by the Free Software Foundation; either
    version 2.1 of the License, or (at your option) any later version.

    This library is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
    Lesser General Public License for more details.

    You should have received a copy of the GNU Lesser General Public
    License along with this library; if not, write to the Free Software
    Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA  02111-1307
    USA

    gxDatabase linear navigation test.
    */
    // ----------------------------------------------------------- //
    #include "gxdlcode.h"

    #if defined (__USE_ANSI_CPP__) // Use the ANSI Standard C++ library
    #include <iostream>
    #include <iomanip>
    using namespace std; // Use unqualified names for Standard C++ library
    #else // Use the old iostream library by default
    #include <iostream.h>
    #include <iomanip.h>
    #endif // __USE_ANSI_CPP__

    #include <string.h>
    #include "gxdbase.h"
    #include "gxfloat.h"
    #include "gxdstats.h"
    #include "ustring.h"

    const int name_length = 16;

    class DatabaseObject
    {
    public:
      DatabaseObject() { name[0] = 0; oid = (gxINT32)0, cid = (gxFLOAT64)0; }
      DatabaseObject(const char *s, long i, double d);

    public:
      friend void *operator new(size_t n, char *s, int i, double d,
    			    gxDatabase *f) {
        void *ptr = new DatabaseObject(s, i, d);
        f->Write(ptr, n, f->Alloc(n));
        return ptr;
      }

    public: // Platform independent data members
      char name[name_length]; // Fixed string type
      gxINT32 oid;            // Integer type
      gxFLOAT64 cid;          // Floating point type
    };

    DatabaseObject::DatabaseObject(const char *s, long i, double d)
    {
      for(int j = 0; j < name_length; j++) name[j] = 0; // Clear the name string
      strcpy(name, s);
      oid = i;
      cid = d;
    }

    void PausePrg()
    {
      cout << "\n";
      cout << "Press enter to continue..." << "\n";
      cin.get();
    }

    int main()
    // Simple demo of how to use the file manager class.
    {
      gxDatabase *f = new gxDatabase;
      const char *fname = "prevnext.gxd";
      UString intbuf;

      cout << "\n";
      cout << "Simple navigation demo." << "\n";
      cout << "Testing gx find functions..." << "\n";
      const int num_to_add = 5;

      if(!gxDatabase::Exists(fname)) {
        cout << "Creating new file..." << "\n";
        f->Create(fname);
        if(CheckError(f) != 0) {
          delete f;
          return 1;
        }
        cout << "Adding " << num_to_add << " objects..." << "\n";
        for(long i = 0; i < num_to_add; i++)
          new("Mouse", i, 2000.101, f) DatabaseObject;
        if(CheckError(f) != 0) {
          delete f;
          return 1;
        }
      }
      else {
        cout << "Opening existing file..." << "\n";
        f->Open(fname);
        if(CheckError(f) != 0) {
          delete f;
          return 1;
        }
      }

      PausePrg();
      DatabaseStats(f);
      PausePrg();

      cout << "Walking through the file finding all blocks..." << "\n";
      FAU_t block_address = 0;
      while(1) {
        block_address = f->FindFirstBlock(block_address);
        if(block_address == FAU_t(0)) break;
        intbuf << clear << block_address;
        cout << "Found block at file address: " << intbuf.c_str() << "\n";
        block_address++; // Offset the block address
      }

      PausePrg();

      cout << "Finding all blocks in reverse order..." << "\n";
      block_address = f->GetEOF();
      while(1) {
        block_address = f->FindPrevBlock(block_address);
        if(block_address == FAU_t(0)) break;
        intbuf << clear << block_address;
        cout << "Found block at file address: " << intbuf.c_str() << "\n";
        block_address++; // Offset the block address
      }

      PausePrg();

      cout << "Walking through the file finding every object..." << "\n";
      FAU_t object_address = 0;
      while(1) {
        object_address = f->FindFirstObject(object_address);
        if(object_address == FAU_t(0)) break;
        intbuf << clear << object_address;
        cout << "Found object at file address: " << intbuf.c_str() << "\n";
        object_address++; // Offset the block address
      }

      PausePrg();

      cout << "Finding every object in reverse order..." << "\n";
      object_address = f->GetEOF();
      while(1) {
        object_address = f->FindPrevObject(object_address);
        if(object_address == FAU_t(0)) break;
        intbuf << clear << object_address;
        cout << "Found object at file address: " << intbuf.c_str() << "\n";
        object_address++; // Offset the block address
      }

      cout << "\n";
      cout << "Exiting..." << "\n";
      f->Close();
      if(CheckError(f) != 0) {
        delete f;
        return 1;
      }

      delete f;
      return 0;
    }
    // ----------------------------------------------------------- //
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