gnu.trove

Class TByteIntHashMap

Implemented Interfaces:
Externalizable

public class TByteIntHashMap
extends TByteHash
implements Externalizable

An open addressed Map implementation for byte keys and int values. Created: Sun Nov 4 08:52:45 2001
Author:
Eric D. Friedman

Field Summary

protected int[]
_values
the values of the map

Constructor Summary

TByteIntHashMap()
Creates a new TByteIntHashMap instance with the default capacity and load factor.
TByteIntHashMap(TByteHashingStrategy strategy)
Creates a new TByteIntHashMap instance with the default capacity and load factor.
TByteIntHashMap(int initialCapacity)
Creates a new TByteIntHashMap instance with a prime capacity equal to or greater than initialCapacity and with the default load factor.
TByteIntHashMap(int initialCapacity, TByteHashingStrategy strategy)
Creates a new TByteIntHashMap instance whose capacity is the next highest prime above initialCapacity + 1 unless that value is already prime.
TByteIntHashMap(int initialCapacity, float loadFactor)
Creates a new TByteIntHashMap instance with a prime capacity equal to or greater than initialCapacity and with the specified load factor.
TByteIntHashMap(int initialCapacity, float loadFactor, TByteHashingStrategy strategy)
Creates a new TByteIntHashMap instance with a prime value at or near the specified capacity and load factor.

Method Summary

int
adjustOrPutValue(byte key, int adjust_amount, int put_amount)
Adjusts the primitive value mapped to the key if the key is present in the map.
boolean
adjustValue(byte key, int amount)
Adjusts the primitive value mapped to key.
void
clear()
Empties the map.
Object
clone()
boolean
containsKey(byte key)
checks for the present of key in the keys of the map.
boolean
containsValue(int val)
checks for the presence of val in the values of the map.
boolean
equals(Object other)
Compares this map with another map for equality of their stored entries.
boolean
forEachEntry(TByteIntProcedure procedure)
Executes procedure for each key/value entry in the map.
boolean
forEachKey(TByteProcedure procedure)
Executes procedure for each key in the map.
boolean
forEachValue(TIntProcedure procedure)
Executes procedure for each value in the map.
int
get(byte key)
retrieves the value for key
int[]
getValues()
Returns the values of the map.
int
hashCode()
boolean
increment(byte key)
Increments the primitive value mapped to key by 1
TByteIntIterator
iterator()
byte[]
keys()
returns the keys of the map.
byte[]
keys(byte[] a)
returns the keys of the map.
int
put(byte key, int value)
Inserts a key/value pair into the map.
void
readExternal(ObjectInput in)
protected void
rehash(int newCapacity)
rehashes the map to the new capacity.
int
remove(byte key)
Deletes a key/value pair from the map.
protected void
removeAt(int index)
removes the mapping at index from the map.
boolean
retainEntries(TByteIntProcedure procedure)
Retains only those entries in the map for which the procedure returns a true value.
protected int
setUp(int initialCapacity)
initializes the hashtable to a prime capacity which is at least initialCapacity + 1.
void
transformValues(TIntFunction function)
Transform the values in this map using function.
void
writeExternal(ObjectOutput out)

Field Details

_values

protected int[] _values
the values of the map

Constructor Details

TByteIntHashMap

public TByteIntHashMap()
Creates a new TByteIntHashMap instance with the default capacity and load factor.

TByteIntHashMap

public TByteIntHashMap(TByteHashingStrategy strategy)
Creates a new TByteIntHashMap instance with the default capacity and load factor.
Parameters:
strategy - used to compute hash codes and to compare keys.

TByteIntHashMap

public TByteIntHashMap(int initialCapacity)
Creates a new TByteIntHashMap instance with a prime capacity equal to or greater than initialCapacity and with the default load factor.
Parameters:
initialCapacity - an int value

TByteIntHashMap

public TByteIntHashMap(int initialCapacity,
                       TByteHashingStrategy strategy)
Creates a new TByteIntHashMap instance whose capacity is the next highest prime above initialCapacity + 1 unless that value is already prime.
Parameters:
initialCapacity - an int value
strategy - used to compute hash codes and to compare keys.

TByteIntHashMap

public TByteIntHashMap(int initialCapacity,
                       float loadFactor)
Creates a new TByteIntHashMap instance with a prime capacity equal to or greater than initialCapacity and with the specified load factor.
Parameters:
initialCapacity - an int value
loadFactor - a float value

TByteIntHashMap

public TByteIntHashMap(int initialCapacity,
                       float loadFactor,
                       TByteHashingStrategy strategy)
Creates a new TByteIntHashMap instance with a prime value at or near the specified capacity and load factor.
Parameters:
initialCapacity - used to find a prime capacity for the table.
loadFactor - used to calculate the threshold over which rehashing takes place.
strategy - used to compute hash codes and to compare keys.

Method Details

adjustOrPutValue

public int adjustOrPutValue(byte key,
                            int adjust_amount,
                            int put_amount)
Adjusts the primitive value mapped to the key if the key is present in the map. Otherwise, the initial_value is put in the map.
Parameters:
key - the key of the value to increment
adjust_amount - the amount to adjust the value by
put_amount - the value put into the map if the key is not initial present
Returns:
the value present in the map after the adjustment or put operation
Since:
2.0b1

adjustValue

public boolean adjustValue(byte key,
                           int amount)
Adjusts the primitive value mapped to key.
Parameters:
key - the key of the value to increment
amount - the amount to adjust the value by.
Returns:
true if a mapping was found and modified.

clear

public void clear()
Empties the map.

clone

public Object clone()
Returns:
a deep clone of this collection

containsKey

public boolean containsKey(byte key)
checks for the present of key in the keys of the map.
Parameters:
key - an byte value
Returns:
a boolean value

containsValue

public boolean containsValue(int val)
checks for the presence of val in the values of the map.
Parameters:
val - an int value
Returns:
a boolean value

equals

public boolean equals(Object other)
Compares this map with another map for equality of their stored entries.
Parameters:
other - an Object value
Returns:
a boolean value

forEachEntry

public boolean forEachEntry(TByteIntProcedure procedure)
Executes procedure for each key/value entry in the map.
Parameters:
procedure - a TOByteIntProcedure value
Returns:
false if the loop over the entries terminated because the procedure returned false for some entry.

forEachKey

public boolean forEachKey(TByteProcedure procedure)
Executes procedure for each key in the map.
Parameters:
procedure - a TByteProcedure value
Returns:
false if the loop over the keys terminated because the procedure returned false for some key.

forEachValue

public boolean forEachValue(TIntProcedure procedure)
Executes procedure for each value in the map.
Parameters:
procedure - a TIntProcedure value
Returns:
false if the loop over the values terminated because the procedure returned false for some value.

get

public int get(byte key)
retrieves the value for key
Parameters:
key - an byte value
Returns:
the value of key or (byte)0 if no such mapping exists.

getValues

public int[] getValues()
Returns the values of the map.
Returns:
a Collection value

hashCode

public int hashCode()

increment

public boolean increment(byte key)
Increments the primitive value mapped to key by 1
Parameters:
key - the key of the value to increment
Returns:
true if a mapping was found and modified.

iterator

public TByteIntIterator iterator()
Returns:
a TByteIntIterator with access to this map's keys and values

keys

public byte[] keys()
returns the keys of the map.
Returns:
a Set value

keys

public byte[] keys(byte[] a)
returns the keys of the map.
Parameters:
a - the array into which the elements of the list are to be stored, if it is big enough; otherwise, a new array of the same type is allocated for this purpose.
Returns:
a Set value

put

public int put(byte key,
               int value)
Inserts a key/value pair into the map.
Parameters:
key - an byte value
value - an int value
Returns:
the previous value associated with key, or (byte)0 if none was found.

readExternal

public void readExternal(ObjectInput in)
            throws IOException,
                   ClassNotFoundException

rehash

protected void rehash(int newCapacity)
rehashes the map to the new capacity.
Parameters:
newCapacity - an int value

remove

public int remove(byte key)
Deletes a key/value pair from the map.
Parameters:
key - an byte value
Returns:
an int value, or (byte)0 if no mapping for key exists

removeAt

protected void removeAt(int index)
removes the mapping at index from the map.
Parameters:
index - an int value

retainEntries

public boolean retainEntries(TByteIntProcedure procedure)
Retains only those entries in the map for which the procedure returns a true value.
Parameters:
procedure - determines which entries to keep
Returns:
true if the map was modified.

setUp

protected int setUp(int initialCapacity)
initializes the hashtable to a prime capacity which is at least initialCapacity + 1.
Parameters:
initialCapacity - an int value
Returns:
the actual capacity chosen

transformValues

public void transformValues(TIntFunction function)
Transform the values in this map using function.
Parameters:
function - a TIntFunction value

writeExternal

public void writeExternal(ObjectOutput out)
            throws IOException

GNU Trove is copyright B) 2001-2008 Eric D. Friedman. All Rights Reserved.