1 /*
2 * Copyright (c) 1997, 2010, 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.
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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
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23 */
24
25 #ifndef SHARE_VM_LIBADT_DICT_HPP
26 #define SHARE_VM_LIBADT_DICT_HPP
27
28 #include "libadt/port.hpp"
29
30 // Dictionaries - An Abstract Data Type
31 //INTERFACE
32 class ostream;
33 class Dict;
34
35 // These dictionaries define a key-value mapping. They can be inserted to,
36 // searched or deleted from. They grow and shrink as needed. The key is a
37 // pointer to something (or anything which can be stored in a pointer). A
38 // key comparison routine determines if two keys are equal or not. A hash
39 // function can be provided; if it's not provided the key itself is used
40 // instead. A nice string hash function is included.
41 typedef int32 (*CmpKey)(const void *key1, const void *key2);
42 typedef int (*Hash)(const void *key);
43 typedef void (*FuncDict)(const void *key, const void *val, Dict *d);
44
45 class Dict : public ResourceObj { // Dictionary structure
46 private:
47 class Arena *_arena; // Where to draw storage from
48 class bucket *_bin; // Hash table is array of buckets
49 uint _size; // Size (# of slots) in hash table
50 uint32 _cnt; // Number of key-value pairs in hash table
51 const Hash _hash; // Hashing function
52 const CmpKey _cmp; // Key comparison function
53 void doubhash( void ); // Double hash table size
54
55 public:
56 friend class DictI; // Friendly iterator function
57
58 // cmp is a key comparision routine. hash is a routine to hash a key.
59 Dict( CmpKey cmp, Hash hash );
60 Dict( CmpKey cmp, Hash hash, Arena *arena, int size=16 );
61 ~Dict();
62
63 Dict( const Dict & ); // Deep-copy guts
64 Dict &operator =( const Dict & );
65
66 // Zap to empty; ready for re-use
67 void Clear();
68
69 // Return # of key-value pairs in dict
70 uint32 Size(void) const { return _cnt; }
71
72 // Insert inserts the given key-value pair into the dictionary. The prior
73 // value of the key is returned; NULL if the key was not previously defined.
74 void *Insert(void *key, void *val, bool replace = true); // A new key-value
75 void *Delete(void *key); // Delete & return old
76
77 // Find finds the value of a given key; or NULL if not found.
78 // The dictionary is NOT changed.
79 void *operator [](const void *key) const; // Do a lookup
80
81 // == compares two dictionaries; they must have the same keys (their keys
82 // must match using CmpKey) and they must have the same values (pointer
83 // comparison). If so 1 is returned, if not 0 is returned.
84 int32 operator ==(const Dict &d) const; // Compare dictionaries for equal
85
86 // Print out the dictionary contents as key-value pairs
87 void print();
88 };
89
90 // Hashing functions
91 int hashstr(const void *s); // Nice string hash
92 // Slimey cheap hash function; no guaranteed performance. Better than the
93 // default for pointers, especially on MS-DOS machines.
94 int hashptr(const void *key);
95 // Slimey cheap hash function; no guaranteed performance.
96 int hashkey(const void *key);
97
98 // Key comparators
99 int32 cmpstr(const void *k1, const void *k2);
100 // Slimey cheap key comparator.
101 int32 cmpkey(const void *key1, const void *key2);
102
103 //------------------------------Iteration--------------------------------------
104 // The class of dictionary iterators. Fails in the presences of modifications
105 // to the dictionary during iteration (including searches).
106 // Usage: for( DictI i(dict); i.test(); ++i ) { body = i.key; body = i.value;}
107 class DictI {
108 private:
109 const Dict *_d; // Dictionary being iterated over
110 uint _i; // Counter over the bins
111 uint _j; // Counter inside each bin
112 public:
113 const void *_key, *_value; // Easy access to the key-value pair
114 DictI( const Dict *d ) {reset(d);}; // Create a new iterator
115 void reset( const Dict *dict ); // Reset existing iterator
116 void operator ++(void); // Increment iterator
117 int test(void) { return _i<_d->_size;} // Test for end of iteration
118 };
119
120 #endif // SHARE_VM_LIBADT_DICT_HPP