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. 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 SHARE_VM_LIBADT_DICT_HPP 26 #define SHARE_VM_LIBADT_DICT_HPP 27 28 // Dictionaries - An Abstract Data Type 29 30 #include "memory/allocation.inline.hpp" 31 #include "memory/resourceArea.hpp" 32 #include "runtime/thread.hpp" 33 34 class Dict; 35 36 // These dictionaries define a key-value mapping. They can be inserted to, 37 // searched or deleted from. They grow and shrink as needed. The key is a 38 // pointer to something (or anything which can be stored in a pointer). A 39 // key comparison routine determines if two keys are equal or not. A hash 40 // function can be provided; if it's not provided the key itself is used 41 // instead. A nice string hash function is included. 42 typedef int32_t (*CmpKey)(const void *key1, const void *key2); 43 typedef int (*Hash)(const void *key); 44 typedef void (*FuncDict)(const void *key, const void *val, Dict *d); 45 46 class Dict : public ResourceObj { // Dictionary structure 47 private: 48 class Arena *_arena; // Where to draw storage from 49 class bucket *_bin; // Hash table is array of buckets 50 uint _size; // Size (# of slots) in hash table 51 uint32_t _cnt; // Number of key-value pairs in hash table 52 const Hash _hash; // Hashing function 53 const CmpKey _cmp; // Key comparison function 54 void doubhash( void ); // Double hash table size 55 56 public: 57 friend class DictI; // Friendly iterator function 58 59 // cmp is a key comparision routine. hash is a routine to hash a key. 60 Dict( CmpKey cmp, Hash hash ); 61 Dict( CmpKey cmp, Hash hash, Arena *arena, int size=16 ); 62 ~Dict(); 63 64 Dict( const Dict & ); // Deep-copy guts 65 Dict &operator =( const Dict & ); 66 67 // Zap to empty; ready for re-use 68 void Clear(); 69 70 // Return # of key-value pairs in dict 71 uint32_t Size(void) const { return _cnt; } 72 73 // Insert inserts the given key-value pair into the dictionary. The prior 74 // value of the key is returned; NULL if the key was not previously defined. 75 void *Insert(void *key, void *val, bool replace = true); // A new key-value 76 void *Delete(void *key); // Delete & return old 77 78 // Find finds the value of a given key; or NULL if not found. 79 // The dictionary is NOT changed. 80 void *operator [](const void *key) const; // Do a lookup 81 82 // == compares two dictionaries; they must have the same keys (their keys 83 // must match using CmpKey) and they must have the same values (pointer 84 // comparison). If so 1 is returned, if not 0 is returned. 85 int32_t operator ==(const Dict &d) const; // Compare dictionaries for equal 86 87 // Print out the dictionary contents as key-value pairs 88 void print(); 89 }; 90 91 // Hashing functions 92 int hashstr(const void *s); // Nice string hash 93 // Slimey cheap hash function; no guaranteed performance. Better than the 94 // default for pointers, especially on MS-DOS machines. 95 int hashptr(const void *key); 96 // Slimey cheap hash function; no guaranteed performance. 97 int hashkey(const void *key); 98 99 // Key comparators 100 int32_t cmpstr(const void *k1, const void *k2); 101 // Slimey cheap key comparator. 102 int32_t cmpkey(const void *key1, const void *key2); 103 104 //------------------------------Iteration-------------------------------------- 105 // The class of dictionary iterators. Fails in the presences of modifications 106 // to the dictionary during iteration (including searches). 107 // Usage: for( DictI i(dict); i.test(); ++i ) { body = i.key; body = i.value;} 108 class DictI { 109 private: 110 const Dict *_d; // Dictionary being iterated over 111 uint _i; // Counter over the bins 112 uint _j; // Counter inside each bin 113 public: 114 const void *_key, *_value; // Easy access to the key-value pair 115 DictI( const Dict *d ) {reset(d);}; // Create a new iterator 116 void reset( const Dict *dict ); // Reset existing iterator 117 void operator ++(void); // Increment iterator 118 int test(void) { return _i<_d->_size;} // Test for end of iteration 119 }; 120 121 #endif // SHARE_VM_LIBADT_DICT_HPP