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Chnaged hash method for dictionary to hash cod + mad

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This commit is contained in:
Giovanni Di Grezia
2014-05-13 10:38:13 +02:00
parent 5099e8d1af
commit 867a7c1a53
7 changed files with 107 additions and 81 deletions
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11
com/xgiovio/HashDictionaryChainingTest.java → com/xgiovio/ChainingHashTableTest.java
View File

@@ -1,8 +1,7 @@
package com.xgiovio;
import dictionary.HashDictionaryChaining;
import dictionary.Logfile;
import exceptions.EmptyListException;
import dictionary.ChainingHashTable;
import dictionary.LogFile;
import priorityqueue.Entry;
import java.security.InvalidKeyException;
@@ -14,13 +13,11 @@ import java.util.Iterator;
* Date: 11/05/2014
* Time: 21:17
*/
public class HashDictionaryChainingTest {
public class ChainingHashTableTest {
public static void main(String[] args) throws InvalidKeyException{
Logfile<String,Integer> def = new Logfile<String, Integer>();
HashDictionaryChaining<String,Integer> h = new HashDictionaryChaining<String, Integer>(def,5);
ChainingHashTable<String,Integer> h = new ChainingHashTable<String, Integer>();
System.out.println(h.load_factor());

8
com/xgiovio/HashDictionaryLinearProbingTest.java → com/xgiovio/LinearProbingHashTableTest.java
View File

@@ -1,6 +1,6 @@
package com.xgiovio;
import dictionary.HashDictionaryLinearProbing;
import dictionary.LinearProbingHashTable;
import priorityqueue.Entry;
import priorityqueue.MyEntry;
@@ -13,13 +13,11 @@ import java.util.Iterator;
* Date: 11/05/2014
* Time: 21:17
*/
public class HashDictionaryLinearProbingTest {
public class LinearProbingHashTableTest {
public static void main(String[] args) throws InvalidKeyException{
MyEntry<String,Integer> def = new MyEntry<String, Integer>("null",0);
HashDictionaryLinearProbing<String,Integer> h = new HashDictionaryLinearProbing(def,5);
LinearProbingHashTable<String,Integer> h = new LinearProbingHashTable();
System.out.println(h.load_factor());

31
com/xgiovio/hash/functions.java
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@@ -1,31 +0,0 @@
package com.xgiovio.hash;
/**
* Created with MONSTER.
* User: xgiovio
* Date: 11/05/2014
* Time: 19:25
*/
public class functions {
//http://m.smithworx.com/cs235/notes/view.php?file=extra%20notes/rodham/35-36-com.xgiovio.hash-tables/HashFunctions.java
public static int hash_horner( String key, int tableSize ) {
int hashVal = 0;
for ( int i = 0; i < key.length(); ++i ) {
hashVal = (hashVal * 37) + key.charAt( i );
}
hashVal %= tableSize;
if ( hashVal < 0 ) {
hashVal += tableSize;
}
return hashVal;
}
}

66
dictionary/HashDictionaryChaining.java → dictionary/ChainingHashTable.java
View File

@@ -5,10 +5,7 @@ import arraylist.IndexList;
import exceptions.HashExceptionKey;
import exceptions.InvalidEntryException;
import position.NodePositionList;
import position.PositionList;
import priorityqueue.Entry;
import priorityqueue.MyEntry;
import sun.rmi.log.ReliableLog;
import java.security.InvalidKeyException;
import java.util.Iterator;
@@ -19,16 +16,28 @@ import java.util.Iterator;
* Date: 11/05/2014
* Time: 19:28
*/
public class HashDictionaryChaining <K,V> implements Dictionary<K,V> {
IndexList<Logfile<K,V>> table = null;
Logfile<K,V> AVAIBLE = null;
//Complete implementation by xgiovio
//Collisions resolved via chaining with LogFile
public class ChainingHashTable<K,V> implements Dictionary<K,V> {
IndexList<LogFile<K,V>> table = null;
LogFile<K,V> AVAIBLE = null;
int avaible_slots = 0;
int elements = 0;
int p = 0;
int scale = 0;
int shift = 0;
public HashDictionaryChaining ( Logfile<K,V> IN_AVAIBLE, int in_size){
table = new ArrayIndexList<Logfile<K, V>>(in_size);
AVAIBLE = IN_AVAIBLE;
public ChainingHashTable(int in_p, int in_size){
table = new ArrayIndexList<LogFile<K, V>>(in_size);
AVAIBLE = new LogFile<K, V>();
p = in_p;
java.util.Random rand = new java.util.Random();
scale = rand.nextInt(p-1) + 1;
shift = rand.nextInt(p);
for (int i= 0 ; i< in_size ;i++){
table.add(i,AVAIBLE);
@@ -36,6 +45,15 @@ public class HashDictionaryChaining <K,V> implements Dictionary<K,V> {
}
}
public ChainingHashTable(int in_size){
this(109345121,in_size);
}
public ChainingHashTable(){
this(109345121,100);
}
public float load_factor () throws InvalidKeyException{
float ret = (size() / (float)raw_size());
if ( ret >= 0.9 ) {
@@ -59,11 +77,8 @@ public class HashDictionaryChaining <K,V> implements Dictionary<K,V> {
return (size() == 0);
}
protected int hash ( K key, int size){
if ( (key instanceof String) )
return com.xgiovio.hash.functions.hash_horner( (String)key ,size );
throw new HashExceptionKey();
protected int hash ( K key){
return (int) ((Math.abs(key.hashCode()*scale + shift) % p) % raw_size());
}
@@ -71,20 +86,20 @@ public class HashDictionaryChaining <K,V> implements Dictionary<K,V> {
public Entry<K, V> find(K key) throws InvalidKeyException {
checkKey(key);
int h = hash(key, raw_size());
int h = hash(key);
if (table.get(h) == AVAIBLE)
return null;
Logfile<K, V> n = table.get(h);
LogFile<K, V> n = table.get(h);
return n.find(key);
}
@Override
public Iterable<Entry<K, V>> findAll(K key) throws InvalidKeyException {
checkKey(key);
int h = hash(key,raw_size());
int h = hash(key);
if (table.get(h) == AVAIBLE)
return null;
Logfile<K, V> n = table.get(h);
LogFile<K, V> n = table.get(h);
return n.entries();
}
@@ -93,15 +108,15 @@ public class HashDictionaryChaining <K,V> implements Dictionary<K,V> {
checkKey(key);
if (load_factor() >= 0.9 )
reformat();
int h = hash(key,raw_size());
int h = hash(key);
if (table.get(h) == AVAIBLE) {
Logfile<K, V> n = new Logfile<K, V>();
LogFile<K, V> n = new LogFile<K, V>();
table.set(h,n);
avaible_slots--;
elements++;
return n.insert(key,value);
} else {
Logfile<K, V> n = table.get(h);
LogFile<K, V> n = table.get(h);
elements++;
return n.insert(key,value);
}
@@ -111,10 +126,10 @@ public class HashDictionaryChaining <K,V> implements Dictionary<K,V> {
public Entry<K, V> remove(Entry<K, V> e) throws InvalidEntryException {
if (e == null)
throw new InvalidEntryException();
int h = hash(e.getKey(),raw_size());
int h = hash(e.getKey());
if (table.get(h) == AVAIBLE)
throw new InvalidEntryException();
Logfile<K, V> n = table.get(h);
LogFile<K, V> n = table.get(h);
Entry<K,V> t = n.remove(e);
elements--;
if (n.size() == 0){
@@ -152,9 +167,12 @@ public class HashDictionaryChaining <K,V> implements Dictionary<K,V> {
Iterable<Entry<K,V>> ite = entries();
int new_size = raw_size() * 2;
IndexList<Logfile<K,V>> table2 = new ArrayIndexList<Logfile<K, V>>(new_size);
IndexList<LogFile<K,V>> table2 = new ArrayIndexList<LogFile<K, V>>(new_size);
avaible_slots = 0;
elements = 0;
java.util.Random rand = new java.util.Random();
scale = rand.nextInt(p-1) + 1; // new hash scaling factor
shift = rand.nextInt(p); //// new hash shifting factor
for (int i= 0 ; i< (new_size) ;i++){
table2.add(i,AVAIBLE);

45
dictionary/HashDictionaryLinearProbing.java → dictionary/LinearProbingHashTable.java
View File

@@ -17,16 +17,27 @@ import java.util.Iterator;
* Date: 11/05/2014
* Time: 19:28
*/
public class HashDictionaryLinearProbing<K,V> implements Dictionary<K,V> {
//Complete implementation by xgiovio
// Collisions resolved with linear probing
public class LinearProbingHashTable<K,V> implements Dictionary<K,V> {
IndexList<Entry<K,V>> table = null;
Entry<K,V> AVAIBLE = null;
int avaible_slots = 0;
int elements = 0;
int p = 0;
int scale = 0;
int shift = 0;
public HashDictionaryLinearProbing(Entry<K, V> IN_AVAIBLE, int in_size){
public LinearProbingHashTable(int in_p, int in_size){
table = new ArrayIndexList<Entry<K, V>>(in_size);
AVAIBLE = IN_AVAIBLE;
AVAIBLE = new MyEntry<K, V>(null,null);
p = in_p;
java.util.Random rand = new java.util.Random();
scale = rand.nextInt(p-1) + 1;
shift = rand.nextInt(p);
for (int i= 0 ; i< in_size ;i++){
table.add(i,AVAIBLE);
@@ -34,6 +45,16 @@ public class HashDictionaryLinearProbing<K,V> implements Dictionary<K,V> {
}
}
public LinearProbingHashTable(int in_size){
this(109345121,in_size);
}
public LinearProbingHashTable(){
this(109345121,100);
}
public float load_factor () throws InvalidKeyException{
float ret = (size() / (float)raw_size());
if ( ret >= 0.5 ) {
@@ -57,11 +78,8 @@ public class HashDictionaryLinearProbing<K,V> implements Dictionary<K,V> {
return (size() == 0);
}
protected int hash ( K key, int size){
if ( (key instanceof String) )
return com.xgiovio.hash.functions.hash_horner( (String)key ,size );
throw new HashExceptionKey();
protected int hash ( K key) {
return (int) ((Math.abs(key.hashCode()*scale + shift) % p) % raw_size());
}
@@ -70,7 +88,7 @@ public class HashDictionaryLinearProbing<K,V> implements Dictionary<K,V> {
public Entry<K, V> find(K key) throws InvalidKeyException {
checkKey(key);
int h = hash(key, raw_size());
int h = hash(key);
int count = 0;
int i = 0;
for (;count < raw_size();){
@@ -88,7 +106,7 @@ public class HashDictionaryLinearProbing<K,V> implements Dictionary<K,V> {
public Iterable<Entry<K, V>> findAll(K key) throws InvalidKeyException {
checkKey(key);
NodePositionList<Entry<K,V>> to_return = new NodePositionList<Entry<K, V>>();
int h = hash(key, raw_size());
int h = hash(key);
int count = 0;
int i = 0;
for (;count < raw_size();){
@@ -107,7 +125,7 @@ public class HashDictionaryLinearProbing<K,V> implements Dictionary<K,V> {
checkKey(key);
if (load_factor() >= 0.5 )
reformat();
int h = hash(key,raw_size());
int h = hash(key);
if (table.get(h) == AVAIBLE) {
MyEntry<K, V> n = new MyEntry<K, V>(key,value);
table.set(h,n);
@@ -136,7 +154,7 @@ public class HashDictionaryLinearProbing<K,V> implements Dictionary<K,V> {
public Entry<K, V> remove(Entry<K, V> e) throws InvalidEntryException {
if (e == null)
throw new InvalidEntryException();
int h = hash(e.getKey(),raw_size());
int h = hash(e.getKey());
if (table.get(h) == AVAIBLE)
throw new InvalidEntryException();
if (table.get(h) == e) {
@@ -192,6 +210,9 @@ public class HashDictionaryLinearProbing<K,V> implements Dictionary<K,V> {
IndexList<Entry<K,V>> table2 = new ArrayIndexList<Entry<K, V>>(new_size);
avaible_slots = 0;
elements = 0;
java.util.Random rand = new java.util.Random();
scale = rand.nextInt(p-1) + 1; // new hash scaling factor
shift = rand.nextInt(p); //// new hash shifting factor
for (int i= 0 ; i< (new_size) ;i++){
table2.add(i,AVAIBLE);

2
dictionary/Logfile.java
View File

@@ -14,7 +14,7 @@ import java.security.InvalidKeyException;
* Date: 11/05/2014
* Time: 19:04
*/
public class Logfile<K,V> implements Dictionary<K,V> {
public class LogFile<K,V> implements Dictionary<K,V> {
NodePositionList<Entry<K,V>> list = new NodePositionList<Entry<K,V>>();

23
map/HashTableMap.java
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@@ -6,6 +6,7 @@ import position.PositionList;
import priorityqueue.Entry;
import java.security.InvalidKeyException;
import java.util.Iterator;
/**
* A hash table data structure that uses linear probing to handle
@@ -181,5 +182,27 @@ public class HashTableMap<K,V> implements Map<K,V> {
return values;
}
public String toString() {
Iterator<Entry<K,V>> it = entries().iterator();
String to_return = "";
to_return = to_return + "[";
for (;it.hasNext();){
Entry<K,V> t = it.next();
if (it.hasNext()) {
to_return+=(t.toString() + " , ");
} else {
to_return+=(t.toString());
}
}
return to_return+= "]";
}
}