include/Field.h

   1 /***************************************************************************
   2  *   Copyright (C) 2007 by www.databasecache.com                           *
   3  *   Contact: praba_tuty@databasecache.com                                 *
   4  *                                                                         *
   5  *   This program is free software; you can redistribute it and/or modify  *
   6  *   it under the terms of the GNU General Public License as published by  *
   7  *   the Free Software Foundation; either version 2 of the License, or     *
   8  *   (at your option) any later version.                                   *
   9  *                                                                         *
  10  *   This program is distributed in the hope that it will be useful,       *
  11  *   but WITHOUT ANY WARRANTY; without even the implied warranty of        *
  12  *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the         *
  13  *   GNU General Public License for more details.                          *
  14  *                                                                         *
  15   ***************************************************************************/
  16 #ifndef FIELD_H
  17 #define FIELD_H
  18 #include<os.h>
  19 #include<DataType.h>
  20 #include<ErrorType.h>
  21
  22 //used by FieldNameList
  23 class FieldNameNode
  24 {
  25     public:
  26     char  fldName[IDENTIFIER_LENGTH];
  27     FieldNameNode *next;
  28 };
  29
  30
  31 class FieldDef
  32 {
  33     public:
  34     FieldDef()
  35     {
  36         type_ = typeUnknown;
  37         length_ = 0;
  38         bindVal_ = NULL;
  39     }
  40     char fldName_[IDENTIFIER_LENGTH];
  41     DataType type_;
  42     size_t length_;
  43     //currently default value is supported for string and binary
  44     //less than length 32 bytes
  45     char defaultValueBuf_[DEFAULT_VALUE_BUF_LENGTH];
  46
  47     //used only in case of binding fields
  48     void *bindVal_;
  49
  50     bool isNull_;
  51     bool isPrimary_;
  52     bool isDefault_;
  53     bool isUnique_;
  54     //TODO::width and scale
  55 };
  56
  57 class FieldNode
  58 {
  59     public:
  60     FieldDef fldDef;
  61     FieldNode *next;
  62 };
  63
  64
  65 class FieldIterator
  66 {
  67     public:
  68     FieldNode *iter;
  69     FieldIterator(FieldNode *ptr) { iter = ptr; }
  70     bool hasElement()
  71     {
  72         if (iter == NULL) return false; else return true;
  73     }
  74     FieldDef nextElement()
  75     {
  76         if (iter == NULL) { FieldDef dummyDef; return dummyDef;}
  77         FieldNode *node = iter;
  78         iter = iter ->next;
  79         return node->fldDef;
  80     }
  81 };
  82
  83 class FieldInfo;
  84
  85 //Internal class used to implement the field list information
  86 //to create the table
  87 class FieldList
  88 {
  89     public:
  90     FieldNode *head;
  91     FieldList(){ head = NULL;}
  92
  93     //TODO::pass by reference instead of value
  94     DbRetVal append(FieldDef fDef);
  95
  96     DbRetVal remove(const char* fldName);
  97
  98     DbRetVal removeAll();
  99
 100     DbRetVal updateBindVal(const char *fldName, void *val);
 101
 102     int getFieldOffset(const char *fldName);
 103     int getFieldOffset(int fldpos);
 104
 105     DataType getFieldType(const char *fldName);
 106
 107     size_t getFieldLength(const char *fldName);
 108
 109     DbRetVal getFieldInfo(const char *fldName, FieldInfo *&info);
 110
 111     int getTupleSize();
 112
 113     FieldIterator getIterator()
 114     {
 115         FieldIterator iter(head);
 116         return iter;
 117     }
 118 };
 119 #endif