package net.minecraft.util;
import cpw.mods.fml.relauncher.Side;
import cpw.mods.fml.relauncher.SideOnly;
import java.util.HashSet;
import java.util.Set;
public class IntHashMap
{
/** An array of HashEntries representing the heads of hash slot lists */
private transient IntHashMapEntry[] slots = new IntHashMapEntry[16];
/** The number of items stored in this map */
private transient int count;
/** The grow threshold */
private int threshold = 12;
/** The scale factor used to determine when to grow the table */
private final float growFactor = 0.75F;
/** A serial stamp used to mark changes */
private transient volatile int versionStamp;
/** The set of all the keys stored in this MCHash object */
private Set keySet = new HashSet();
/**
* Makes the passed in integer suitable for hashing by a number of shifts
*/
private static int computeHash(int par0)
{
par0 ^= par0 >>> 20 ^ par0 >>> 12;
return par0 ^ par0 >>> 7 ^ par0 >>> 4;
}
/**
* Computes the index of the slot for the hash and slot count passed in.
*/
private static int getSlotIndex(int par0, int par1)
{
return par0 & par1 - 1;
}
/**
* Returns the object associated to a key
*/
public Object lookup(int par1)
{
int var2 = computeHash(par1);
for (IntHashMapEntry var3 = this.slots[getSlotIndex(var2, this.slots.length)]; var3 != null; var3 = var3.nextEntry)
{
if (var3.hashEntry == par1)
{
return var3.valueEntry;
}
}
return null;
}
/**
* Return true if an object is associated with the given key
*/
public boolean containsItem(int par1)
{
return this.lookupEntry(par1) != null;
}
/**
* Returns the key/object mapping for a given key as a MCHashEntry
*/
final IntHashMapEntry lookupEntry(int par1)
{
int var2 = computeHash(par1);
for (IntHashMapEntry var3 = this.slots[getSlotIndex(var2, this.slots.length)]; var3 != null; var3 = var3.nextEntry)
{
if (var3.hashEntry == par1)
{
return var3;
}
}
return null;
}
/**
* Adds a key and associated value to this map
*/
public void addKey(int par1, Object par2Obj)
{
this.keySet.add(Integer.valueOf(par1));
int var3 = computeHash(par1);
int var4 = getSlotIndex(var3, this.slots.length);
for (IntHashMapEntry var5 = this.slots[var4]; var5 != null; var5 = var5.nextEntry)
{
if (var5.hashEntry == par1)
{
var5.valueEntry = par2Obj;
return;
}
}
++this.versionStamp;
this.insert(var3, par1, par2Obj, var4);
}
/**
* Increases the number of hash slots
*/
private void grow(int par1)
{
IntHashMapEntry[] var2 = this.slots;
int var3 = var2.length;
if (var3 == 1073741824)
{
this.threshold = Integer.MAX_VALUE;
}
else
{
IntHashMapEntry[] var4 = new IntHashMapEntry[par1];
this.copyTo(var4);
this.slots = var4;
this.threshold = (int)((float)par1 * this.growFactor);
}
}
/**
* Copies the hash slots to a new array
*/
private void copyTo(IntHashMapEntry[] par1ArrayOfIntHashMapEntry)
{
IntHashMapEntry[] var2 = this.slots;
int var3 = par1ArrayOfIntHashMapEntry.length;
for (int var4 = 0; var4 < var2.length; ++var4)
{
IntHashMapEntry var5 = var2[var4];
if (var5 != null)
{
var2[var4] = null;
IntHashMapEntry var6;
do
{
var6 = var5.nextEntry;
int var7 = getSlotIndex(var5.slotHash, var3);
var5.nextEntry = par1ArrayOfIntHashMapEntry[var7];
par1ArrayOfIntHashMapEntry[var7] = var5;
var5 = var6;
}
while (var6 != null);
}
}
}
/**
* Removes the specified object from the map and returns it
*/
public Object removeObject(int par1)
{
this.keySet.remove(Integer.valueOf(par1));
IntHashMapEntry var2 = this.removeEntry(par1);
return var2 == null ? null : var2.valueEntry;
}
/**
* Removes the specified entry from the map and returns it
*/
final IntHashMapEntry removeEntry(int par1)
{
int var2 = computeHash(par1);
int var3 = getSlotIndex(var2, this.slots.length);
IntHashMapEntry var4 = this.slots[var3];
IntHashMapEntry var5;
IntHashMapEntry var6;
for (var5 = var4; var5 != null; var5 = var6)
{
var6 = var5.nextEntry;
if (var5.hashEntry == par1)
{
++this.versionStamp;
--this.count;
if (var4 == var5)
{
this.slots[var3] = var6;
}
else
{
var4.nextEntry = var6;
}
return var5;
}
var4 = var5;
}
return var5;
}
/**
* Removes all entries from the map
*/
public void clearMap()
{
++this.versionStamp;
IntHashMapEntry[] var1 = this.slots;
for (int var2 = 0; var2 < var1.length; ++var2)
{
var1[var2] = null;
}
this.count = 0;
}
/**
* Adds an object to a slot
*/
private void insert(int par1, int par2, Object par3Obj, int par4)
{
IntHashMapEntry var5 = this.slots[par4];
this.slots[par4] = new IntHashMapEntry(par1, par2, par3Obj, var5);
if (this.count++ >= this.threshold)
{
this.grow(2 * this.slots.length);
}
}
@SideOnly(Side.CLIENT)
/**
* Return the Set of all keys stored in this MCHash object
*/
public Set getKeySet()
{
return this.keySet;
}
/**
* Returns the hash code for a key
*/
static int getHash(int par0)
{
return computeHash(par0);
}
}