1    	/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
2    	/*                                                                           */
3    	/*                  This file is part of the class library                   */
4    	/*       SoPlex --- the Sequential object-oriented simPlex.                  */
5    	/*                                                                           */
6    	/*  Copyright (c) 1996-2023 Zuse Institute Berlin (ZIB)                      */
7    	/*                                                                           */
8    	/*  Licensed under the Apache License, Version 2.0 (the "License");          */
9    	/*  you may not use this file except in compliance with the License.         */
10   	/*  You may obtain a copy of the License at                                  */
11   	/*                                                                           */
12   	/*      http://www.apache.org/licenses/LICENSE-2.0                           */
13   	/*                                                                           */
14   	/*  Unless required by applicable law or agreed to in writing, software      */
15   	/*  distributed under the License is distributed on an "AS IS" BASIS,        */
16   	/*  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. */
17   	/*  See the License for the specific language governing permissions and      */
18   	/*  limitations under the License.                                           */
19   	/*                                                                           */
20   	/*  You should have received a copy of the Apache-2.0 license                */
21   	/*  along with SoPlex; see the file LICENSE. If not email to soplex@zib.de.  */
22   	/*                                                                           */
23   	/* * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * * */
24   	
25   	/**@file  datakey.h
26   	 * @brief Entry identifier class for items of a DataSet.
27   	 */
28   	#ifndef _DATAKEY_H_
29   	#define _DATAKEY_H_
30   	
31   	#include <assert.h>
32   	
33   	namespace soplex
34   	{
35   	/**@brief   Entry identifier class for items of a DataSet.
36   	   @ingroup Elementary
37   	
38   	   Every item in a DataSet is assigned a DataKey by which it can be
39   	   accessed (using DataSet::operator[]()). A DataKey consists of an integer
40   	   member #idx, which is a positive number for any valid DataKey. No
41   	   #idx of an element in a DataSet may exceed the sets max().
42   	   This property may be used to build arrays with additional information to
43   	   the elements of a DataSet.
44   	
45   	   In addition, #DataKey%s provide a member #info which can be used to store
46   	   further information.
47   	
48   	   Each DataKey is unique for one DataSet but different DataSets may (and
49   	   generally will) manage the same #DataKey%s. When an element is removed from
50   	   a DataSet its DataKey may (and generally will) be reused for other
51   	   elements added to the DataSet later on.
52   	
53   	   @todo data members should be private.
54   	*/
55   	class DataKey
56   	{
57   	public:
58   	
59   	   //-------------------------------------
60   	   /**@name Data */
61   	   ///@{
62   	   /* This was originally implemented as bitfield "signed int info: 2; signed int idx: (8 * sizeof(int) - 2);",
63   	      however, this seems to trigger a bug with old versions of GCC/glibc on 32bit machines. */
64   	   int info;                                  ///< user information to store values -1, 0, +1
65   	   int idx;                                   ///< (locally) unique key index
66   	   ///@}
67   	
68   	public:
69   	
70   	   //-------------------------------------
71   	   /**@name Constructors / destructors */
72   	   ///@{
73   	   /// Default constructor. Constructs an invalid DataKey.
74   	   DataKey()
75   	      : info(0), idx(-1)
76   	   {}
77   	   // Full constructor
78   	   DataKey(int p_info, int p_idx)
79   	      : info(p_info)
80   	      , idx(p_idx)
81   	   {
82   	      assert(p_info <= 1 && p_info >= -1);
83   	   }
84   	
85   	   ///@}
86   	
87   	   //-------------------------------------
88   	   /**@name Access / modification */
89   	   ///@{
90   	   /// gets the index number (\ref soplex::DataKey::idx "idx") of the DataKey.
91   	   inline int getIdx() const
92   	   {
93   	      return idx;
94   	   }
95   	   /// sets the index number (\ref soplex::DataKey::idx "idx") of the DataKey.
96   	   inline void setIdx(int p_idx)
97   	   {
98   	      idx = p_idx;
99   	   }
100  	   /// returns TRUE, iff the DataKey is valid.
101  	   inline bool isValid() const
102  	   {
103  	      return idx >= 0;
104  	   }
105  	   /// makes the DataKey invalid and clears the \ref soplex::DataKey::info "info" field.
106  	   inline void inValidate()
107  	   {
108  	      idx  = -1;
109  	      info = 0;
110  	   }
111  	   ///@}
112  	
113  	};
114  	
115  	} // namespace soplex
116  	#endif // _DATAKEY_H_
117