2001-10-16 09:26:59 +00:00

351 lines
8.7 KiB
C++

/*
* The contents of this file are subject to the Mozilla Public
* License Version 1.1 (the "License"); you may not use this file
* except in compliance with the License. You may obtain a copy of
* the License at http://www.mozilla.org/MPL/
*
* Software distributed under the License is distributed on an "AS
* IS" basis, WITHOUT WARRANTY OF ANY KIND, either express or
* implied. See the License for the specific language governing
* rights and limitations under the License.
*
* The Original Code is TransforMiiX XSLT processor.
*
* The Initial Developer of the Original Code is The MITRE Corporation.
* Portions created by MITRE are Copyright (C) 1999 The MITRE Corporation.
*
* Portions created by Keith Visco as a Non MITRE employee,
* (C) 1999 Keith Visco. All Rights Reserved.
*
* Contributor(s):
* Keith Visco, kvisco@ziplink.net
* -- original author.
*
* Bob Miller, Oblix Inc., kbob@oblix.com
* -- fixed memory leak in NamedMap::hashKey method by deleting
* up char[] chars;
*
*/
/**
* A Named Map for TxObjects
**/
#include "NamedMap.h"
//-------------/
//- Constants -/
//-------------/
const int NamedMap::DEFAULT_SIZE = 17;
//----------------/
//- Constructors -/
//----------------/
/**
* Creates a new NamedMap with the default Size
**/
NamedMap::NamedMap() {
initialize(DEFAULT_SIZE);
} //-- NamedMap
/**
* Creates a new NamedMap with the specified number of buckets
**/
NamedMap::NamedMap(int size) {
initialize(size);
} //-- NamedMap
/**
* Helper method for Constructors
**/
void NamedMap::initialize(PRInt32 size) {
//-- by default the NamedMap will not delete it's
//-- object references
doObjectDeletion = MB_FALSE;
//-- create a new array of bucket pointers
elements = new BucketItem*[size];
//-- initialize all elements to 0;
for ( PRInt32 i = 0; i < size; i++ ) elements[i] = 0;
numberOfBuckets = size;
numberOfElements = 0;
} //-- initialize
/**
* Destructor for NamedMap
**/
NamedMap::~NamedMap() {
clear();
delete [] elements;
} //-- ~NamedMap
/**
* Removes all elements from the NamedMap. If the object deletion flag
* has been set to true (by a call to setObjectDeletion) objects
* will also be deleted as they are removed from the map
**/
void NamedMap::clear() {
clear(doObjectDeletion);
} //-- clear
/**
* Removes all elements from the NamedMap
**/
void NamedMap::clear(MBool deleteObjects) {
for (int i = 0; i < numberOfBuckets; i++) {
BucketItem* bktItem = elements[i];
while (bktItem) {
BucketItem* tItem = bktItem;
bktItem = bktItem->next;
//-- repoint item to 0 to prevent deletion
if ( ! deleteObjects ) tItem->item = 0;
else {
delete tItem->item;
}
//--delete tItem;
delete tItem;
}
}
numberOfElements = 0;
} //-- clear
void NamedMap::dumpMap() {
#if 0
// XXX DEBUG OUTPUT
cout << "#NamedMap -------- { "<<endl;
for (int i = 0; i < numberOfBuckets; i++) {
cout << "[";
if (i < 10 ) cout << '0';
cout << i << "]->{";
BucketItem* item = elements[i];
MBool hasPrevItem = MB_FALSE;
while (item) {
if (hasPrevItem) cout << ", ";
cout << item->key;
hasPrevItem = MB_TRUE;
item = item->next;
}
cout << "}"<<endl;
}
cout <<"} #NamedMap"<<endl;
#endif
} //-- dumpMap
/**
* Returns the object reference in this Map associated with the given name
* @return the object reference in this Map associated with the given name
**/
TxObject* NamedMap::get(const char* key) {
String sKey = key;
return get(sKey);
} //-- get
/**
* Returns the object reference in this Map associated with the given name
* @return the object reference in this Map associated with the given name
**/
TxObject* NamedMap::get(const String& key) {
BucketItem* item = getBucketItem(key);
if ( item ) return item->item;
return 0;
} //-- get
/**
* Returns true if there are no objects in this map.
* @return true if there are no objects in this map.
**/
MBool NamedMap::isEmpty() {
return (numberOfElements == 0) ? MB_TRUE : MB_FALSE;
} //-- isEmpty
/**
* Returns a StringList of all the keys in this NamedMap.
* Please delete this List when you are done with it
**/
StringList* NamedMap::keys() {
StringList* list = new StringList();
if (!list)
return NULL;
for (int i = 0; i < numberOfBuckets; i++) {
BucketItem* item = elements[i];
while (item) {
list->add(new String(item->key));
item = item->next;
}
}
return list;
} //-- keys
/**
* Adds the specified Node to the top of this Stack.
* @param node the Node to add to the top of the Stack
**/
void NamedMap::put(const char* key, TxObject* obj) {
String sKey = key;
put(sKey, obj);
} //-- put
/**
* Adds the specified Node to the top of this Stack.
* @param node the Node to add to the top of the Stack
**/
void NamedMap::put(const String& key, TxObject* obj) {
//-- compute hash for key
unsigned long hashCode = hashKey(key);
//-- calculate index
int idx = hashCode % numberOfBuckets;
//-- fetch first item in bucket
BucketItem* bktItem = elements[idx];
//-- if bktItem is 0 then there are no items is this Bucket,
//-- add to front of list
if ( !bktItem ) {
elements[idx] = createBucketItem(key, obj);
++numberOfElements;
}
//-- find current item, or add to end of list
else {
BucketItem* prevItem = bktItem;
//-- advance to next spot
while ( bktItem ) {
//-- if current key equals desired key, break
if ( bktItem->key.isEqual(key) ) {
break;
}
prevItem = bktItem;
bktItem = bktItem->next;
}
//-- if we did not find a bucket Item create a new one
if ( !bktItem) {
bktItem = createBucketItem(key, obj);
prevItem->next = bktItem;
bktItem->prev = prevItem;
++numberOfElements;
}
//-- we found bucket item, just set value
else {
if (doObjectDeletion)
delete bktItem->item;
bktItem->item = obj;
}
}
} //-- put
/**
* Removes the the specified Object from the NamedMap
* @param key the key of the Object to remove from the NamedMap
* @return the Object being removed
**/
TxObject* NamedMap::remove(const String& key) {
// compute hash for key
long hashCode = hashKey(key);
int idx = hashCode % numberOfBuckets;
BucketItem* bktItem = elements[idx];
while ( bktItem && !(key.isEqual(bktItem->key))) {
bktItem = bktItem->next;
}
if ( bktItem ) {
if (bktItem == elements[idx]) elements[idx] = bktItem->next;
else {
bktItem->prev->next = bktItem->next;
if (bktItem->next)
bktItem->next->prev = bktItem->prev;
};
numberOfElements--;
TxObject* txObject = bktItem->item;
bktItem->item = 0;
delete bktItem;
return txObject;
}
return 0;
} //-- remove
/**
* Sets the object deletion flag. If set to true, objects in
* the NamedMap will be deleted upon calling the clear() method, or
* upon destruction. By default this is false.
**/
void NamedMap::setObjectDeletion(MBool deleteObjects) {
doObjectDeletion = deleteObjects;
} //-- setObjectDeletion
/**
* Returns the number of elements in the NodeStack
* @return the number of elements in the NodeStack
**/
int NamedMap::size() {
return numberOfElements;
} //-- size
//-------------------/
//- Private Methods -/
//-------------------/
NamedMap::BucketItem* NamedMap::createBucketItem(const String& key, TxObject* objPtr)
{
BucketItem* bktItem = new BucketItem;
if (bktItem) {
bktItem->next = 0;
bktItem->prev = 0;
bktItem->key = key;
bktItem->item = objPtr;
}
return bktItem;
} //-- createBucketItem
NamedMap::BucketItem* NamedMap::getBucketItem(const String& key) {
// compute hash for key
long hashCode = hashKey(key);
int idx = hashCode % numberOfBuckets;
BucketItem* bktItem = elements[idx];
while ( bktItem ) {
if ( bktItem->key.isEqual(key) ) return bktItem;
bktItem = bktItem->next;
}
return bktItem;
} //-- getBucketItem
/**
**/
unsigned long NamedMap::hashKey(const String& key) {
PRInt32 len = key.length();
UNICODE_CHAR* chars = new UNICODE_CHAR[len];
key.toUnicode(chars);
unsigned long hashCode = 0;
for (PRInt32 i = 0; i < len; i++) {
hashCode += ((PRInt32)chars[i]) << 3;
}
delete [] chars;
return hashCode;
} //-- hashKey