dict.hpp revision 1472:c18cbe5936b8
1/* 2 * Copyright (c) 1997, 2003, Oracle and/or its affiliates. All rights reserved. 3 * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. 4 * 5 * This code is free software; you can redistribute it and/or modify it 6 * under the terms of the GNU General Public License version 2 only, as 7 * published by the Free Software Foundation. 8 * 9 * This code is distributed in the hope that it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License 12 * version 2 for more details (a copy is included in the LICENSE file that 13 * accompanied this code). 14 * 15 * You should have received a copy of the GNU General Public License version 16 * 2 along with this work; if not, write to the Free Software Foundation, 17 * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. 18 * 19 * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA 20 * or visit www.oracle.com if you need additional information or have any 21 * questions. 22 * 23 */ 24 25#ifndef _DICT_ 26#define _DICT_ 27// Dictionaries - An Abstract Data Type 28//INTERFACE 29class ostream; 30class Dict; 31 32// These dictionaries define a key-value mapping. They can be inserted to, 33// searched or deleted from. They grow and shrink as needed. The key is a 34// pointer to something (or anything which can be stored in a pointer). A 35// key comparison routine determines if two keys are equal or not. A hash 36// function can be provided; if it's not provided the key itself is used 37// instead. A nice string hash function is included. 38typedef int32 (*CmpKey)(const void *key1, const void *key2); 39typedef int (*Hash)(const void *key); 40typedef void (*FuncDict)(const void *key, const void *val, Dict *d); 41 42class Dict : public ResourceObj { // Dictionary structure 43 private: 44 class Arena *_arena; // Where to draw storage from 45 class bucket *_bin; // Hash table is array of buckets 46 uint _size; // Size (# of slots) in hash table 47 uint32 _cnt; // Number of key-value pairs in hash table 48 const Hash _hash; // Hashing function 49 const CmpKey _cmp; // Key comparison function 50 void doubhash( void ); // Double hash table size 51 52 public: 53 friend class DictI; // Friendly iterator function 54 55 // cmp is a key comparision routine. hash is a routine to hash a key. 56 Dict( CmpKey cmp, Hash hash ); 57 Dict( CmpKey cmp, Hash hash, Arena *arena, int size=16 ); 58 ~Dict(); 59 60 Dict( const Dict & ); // Deep-copy guts 61 Dict &operator =( const Dict & ); 62 63 // Zap to empty; ready for re-use 64 void Clear(); 65 66 // Return # of key-value pairs in dict 67 uint32 Size(void) const { return _cnt; } 68 69 // Insert inserts the given key-value pair into the dictionary. The prior 70 // value of the key is returned; NULL if the key was not previously defined. 71 void *Insert(void *key, void *val, bool replace = true); // A new key-value 72 void *Delete(void *key); // Delete & return old 73 74 // Find finds the value of a given key; or NULL if not found. 75 // The dictionary is NOT changed. 76 void *operator [](const void *key) const; // Do a lookup 77 78 // == compares two dictionaries; they must have the same keys (their keys 79 // must match using CmpKey) and they must have the same values (pointer 80 // comparison). If so 1 is returned, if not 0 is returned. 81 int32 operator ==(const Dict &d) const; // Compare dictionaries for equal 82 83 // Print out the dictionary contents as key-value pairs 84 void print(); 85}; 86 87// Hashing functions 88int hashstr(const void *s); // Nice string hash 89// Slimey cheap hash function; no guaranteed performance. Better than the 90// default for pointers, especially on MS-DOS machines. 91int hashptr(const void *key); 92// Slimey cheap hash function; no guaranteed performance. 93int hashkey(const void *key); 94 95// Key comparators 96int32 cmpstr(const void *k1, const void *k2); 97// Slimey cheap key comparator. 98int32 cmpkey(const void *key1, const void *key2); 99 100//------------------------------Iteration-------------------------------------- 101// The class of dictionary iterators. Fails in the presences of modifications 102// to the dictionary during iteration (including searches). 103// Usage: for( DictI i(dict); i.test(); ++i ) { body = i.key; body = i.value;} 104class DictI { 105 private: 106 const Dict *_d; // Dictionary being iterated over 107 uint _i; // Counter over the bins 108 uint _j; // Counter inside each bin 109 public: 110 const void *_key, *_value; // Easy access to the key-value pair 111 DictI( const Dict *d ) {reset(d);}; // Create a new iterator 112 void reset( const Dict *dict ); // Reset existing iterator 113 void operator ++(void); // Increment iterator 114 int test(void) { return _i<_d->_size;} // Test for end of iteration 115}; 116 117#endif // _DICT_ 118