gnu.trove.map.hash

Class TByteObjectHashMap<V>

java.lang.Object

gnu.trove.impl.hash.THash

gnu.trove.impl.hash.TPrimitiveHash

gnu.trove.impl.hash.TByteHash

gnu.trove.map.hash.TByteObjectHashMap<V>

All Implemented Interfaces:

TByteObjectMap<V>, java.io.Externalizable, java.io.Serializable

public class TByteObjectHashMap<V>
extends TByteHash
implements TByteObjectMap<V>, java.io.Externalizable

An open addressed Map implementation for byte keys and Object values. Created: Sun Nov 4 08:52:45 2001

See Also:

Serialized Form

Nested Class Summary

Nested Classes

Modifier and Type	Class and Description
protected class	TByteObjectHashMap.ValueView a view onto the values of the map.

Field Summary

Fields

Modifier and Type	Field and Description
protected V[]	_values the values of the map
protected byte	no_entry_key the value that represents null in the key set.

Fields inherited from class gnu.trove.impl.hash.TByteHash

_set, consumeFreeSlot, no_entry_value

Fields inherited from class gnu.trove.impl.hash.TPrimitiveHash

_states, FREE, FULL, REMOVED

Fields inherited from class gnu.trove.impl.hash.THash

_autoCompactionFactor, _autoCompactRemovesRemaining, _autoCompactTemporaryDisable, _free, _loadFactor, _maxSize, _size, DEFAULT_CAPACITY, DEFAULT_LOAD_FACTOR

Constructor Summary

Constructors

Constructor and Description
TByteObjectHashMap() Creates a new TByteObjectHashMap instance with the default capacity and load factor.
TByteObjectHashMap(int initialCapacity) Creates a new TByteObjectHashMap instance with a prime capacity equal to or greater than initialCapacity and with the default load factor.
TByteObjectHashMap(int initialCapacity, float loadFactor) Creates a new TByteObjectHashMap instance with a prime capacity equal to or greater than initialCapacity and with the specified load factor.
TByteObjectHashMap(int initialCapacity, float loadFactor, byte noEntryKey) Creates a new TByteObjectHashMap instance with a prime value at or near the specified capacity and load factor.
TByteObjectHashMap(TByteObjectMap<? extends V> map) Creates a new TByteObjectHashMap that contains the entries in the map passed to it.

Method Summary

Modifier and Type	Method and Description
void	clear() Empties the collection.
boolean	containsKey(byte key) Returns true if this map contains a mapping for the specified key.
boolean	containsValue(java.lang.Object val) Returns true if this map maps one or more keys to the specified value.
boolean	equals(java.lang.Object other) Compares the specified object with this map for equality.
boolean	forEachEntry(TByteObjectProcedure<? super V> 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(TObjectProcedure<? super V> procedure) Executes procedure for each value in the map.
V	get(byte key) Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.
byte	getNoEntryKey() Returns the value that represents null in the TByteObjectMap.keySet().
int	hashCode() Returns the hash code value for this map.
TByteObjectIterator<V>	iterator() Returns a TByteObjectIterator with access to this map's keys and values.
byte[]	keys() Returns a copy of the keys of the map as an array.
byte[]	keys(byte[] dest) Returns a copy of the keys of the map as an array.
TByteSet	keySet() Returns a TByteSet view of the keys contained in this map.
V	put(byte key, V value) Associates the specified value with the specified key in this map (optional operation).
void	putAll(java.util.Map<? extends java.lang.Byte,? extends V> map) Copies all of the mappings from the specified map to this map (optional operation).
void	putAll(TByteObjectMap<? extends V> map) Put all the entries from the given map into this map.
V	putIfAbsent(byte key, V value) Inserts a key/value pair into the map if the specified key is not already associated with a value.
void	readExternal(java.io.ObjectInput in)
protected void	rehash(int newCapacity) Rehashes the set.
V	remove(byte key) Removes the mapping for a key from this map if it is present (optional operation).
protected void	removeAt(int index) Releases the element currently stored at index.
boolean	retainEntries(TByteObjectProcedure<? super V> 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.
java.lang.String	toString()
void	transformValues(TObjectFunction<V,V> function) Transform the values in this map using function.
java.util.Collection<V>	valueCollection() Returns a Collection view of the values contained in this map.
java.lang.Object[]	values() Returns the values of the map as an Object array.
V[]	values(V[] dest) Returns the values of the map using an existing array.
void	writeExternal(java.io.ObjectOutput out)

Methods inherited from class gnu.trove.impl.hash.TByteHash

contains, forEach, getNoEntryValue, index, insertKey

Methods inherited from class gnu.trove.impl.hash.TPrimitiveHash

capacity

Methods inherited from class gnu.trove.impl.hash.THash

calculateGrownCapacity, compact, computeMaxSize, computeNextAutoCompactionAmount, ensureCapacity, fastCeil, getAutoCompactionFactor, isEmpty, postInsertHook, reenableAutoCompaction, saturatedCast, setAutoCompactionFactor, size, tempDisableAutoCompaction, trimToSize

Methods inherited from class java.lang.Object

clone, finalize, getClass, notify, notifyAll, wait, wait, wait

Methods inherited from interface gnu.trove.map.TByteObjectMap

isEmpty, size

Field Detail

_values

protected transient V[] _values

the values of the map

no_entry_key

protected byte no_entry_key

the value that represents null in the key set.

Constructor Detail

TByteObjectHashMap

public TByteObjectHashMap()

Creates a new TByteObjectHashMap instance with the default capacity and load factor.

TByteObjectHashMap

public TByteObjectHashMap(int initialCapacity)

Creates a new TByteObjectHashMap instance with a prime capacity equal to or greater than initialCapacity and with the default load factor.

Parameters:

initialCapacity - an int value

TByteObjectHashMap

public TByteObjectHashMap(int initialCapacity,
                          float loadFactor)

Creates a new TByteObjectHashMap 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

TByteObjectHashMap

public TByteObjectHashMap(int initialCapacity,
                          float loadFactor,
                          byte noEntryKey)

Creates a new TByteObjectHashMap 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.

noEntryKey - the value used to represent null in the key set.

TByteObjectHashMap

public TByteObjectHashMap(TByteObjectMap<? extends V> map)

Creates a new TByteObjectHashMap that contains the entries in the map passed to it.

Parameters:

map - the TByteObjectMap to be copied.

Method Detail

setUp

protected int setUp(int initialCapacity)

initializes the hashtable to a prime capacity which is at least initialCapacity + 1.

Overrides:

setUp in class TByteHash

Parameters:

initialCapacity - an int value

Returns:

the actual capacity chosen

rehash

protected void rehash(int newCapacity)

Rehashes the set.

Specified by:

rehash in class THash

Parameters:

newCapacity - an int value

getNoEntryKey

public byte getNoEntryKey()

Returns the value that represents null in the TByteObjectMap.keySet(). The default value is generally zero, but can be configured during construction of the collection.

Specified by:

getNoEntryKey in interface TByteObjectMap<V>

Returns:

the value that represents a null value in this collection.

containsKey

public boolean containsKey(byte key)

Returns true if this map contains a mapping for the specified key. More formally, returns true if and only if this map contains a mapping for a key k such that key.equals(k). (There can be at most one such mapping.)

Specified by:

containsKey in interface TByteObjectMap<V>

Parameters:

key - key whose presence in this map is to be tested

Returns:

true if this map contains a mapping for the specified key

containsValue

public boolean containsValue(java.lang.Object val)

Returns true if this map maps one or more keys to the specified value. More formally, returns true if and only if this map contains at least one mapping to a value v such that (value==null ? v==null : value.equals(v)). This operation will probably require time linear in the map size for most implementations of the Map interface.

Specified by:

containsValue in interface TByteObjectMap<V>

Parameters:

val - value whose presence in this map is to be tested

Returns:

true if this map maps one or more keys to the specified value

get

public V get(byte key)

Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.

More formally, if this map contains a mapping from a key k to a value v such that (key==null ? k==null : key.equals(k)), then this method returns v; otherwise it returns null. (There can be at most one such mapping.)

If this map permits null values, then a return value of null does not necessarily indicate that the map contains no mapping for the key; it's also possible that the map explicitly maps the key to null. The containsKey operation may be used to distinguish these two cases.

Specified by:

get in interface TByteObjectMap<V>

Parameters:

key - the key whose associated value is to be returned

Returns:

the byte value to which the specified key is mapped, or null if this map contains no mapping for the key

put

public V put(byte key,
             V value)

Associates the specified value with the specified key in this map (optional operation). If the map previously contained a mapping for the key, the old value is replaced by the specified value. (A map m is said to contain a mapping for a key k if and only if m.containsKey(k) would return true.)

Specified by:

put in interface TByteObjectMap<V>

Parameters:

key - key with which the specified value is to be associated

value - an byte value value to be associated with the specified key

Returns:

the previous value associated with key, or no_entry_value if there was no mapping for key. (A no_entry_value return can also indicate that the map previously associated null with key, if the implementation supports null values.)

See Also:

TByteObjectMap.getNoEntryKey()

putIfAbsent

public V putIfAbsent(byte key,
                     V value)

Inserts a key/value pair into the map if the specified key is not already associated with a value.

Specified by:

putIfAbsent in interface TByteObjectMap<V>

Parameters:

key - key with which the specified value is to be associated

value - an byte value to be associated with the specified key

Returns:

the previous value associated with key, or null if none was found.

remove

public V remove(byte key)

Removes the mapping for a key from this map if it is present (optional operation). More formally, if this map contains a mapping from key k to value v such that key.equals(k), that mapping is removed. (The map can contain at most one such mapping.)

Returns the value to which this map previously associated the key, or null if the map contained no mapping for the key.

If this map permits null values, then a return value of null does not necessarily indicate that the map contained no mapping for the key; it's also possible that the map explicitly mapped the key to null.

The map will not contain a mapping for the specified key once the call returns.

Specified by:

remove in interface TByteObjectMap<V>

Parameters:

key - key whose mapping is to be removed from the map

Returns:

the previous byte value associated with key, or null if there was no mapping for key.

removeAt

protected void removeAt(int index)

Releases the element currently stored at index.

Overrides:

removeAt in class TByteHash

Parameters:

index - an int value

putAll

public void putAll(java.util.Map<? extends java.lang.Byte,? extends V> map)

Copies all of the mappings from the specified map to this map (optional operation). The effect of this call is equivalent to that of calling put(k, v) on this map once for each mapping from key k to value v in the specified map. The behavior of this operation is undefined if the specified map is modified while the operation is in progress.

Specified by:

putAll in interface TByteObjectMap<V>

Parameters:

map - mappings to be stored in this map

putAll

public void putAll(TByteObjectMap<? extends V> map)

Put all the entries from the given map into this map.

Specified by:

putAll in interface TByteObjectMap<V>

Parameters:

map - The map from which entries will be obtained to put into this map.

clear

public void clear()

Empties the collection.

Specified by:

clear in interface TByteObjectMap<V>

Overrides:

clear in class THash

keySet

public TByteSet keySet()

Returns a TByteSet view of the keys contained in this map. The set is backed by the map, so changes to the map are reflected in the set, and vice-versa. If the map is modified while an iteration over the set is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The set supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Set.remove, removeAll, retainAll, and clear operations. It does not support the add or addAll operations.

Specified by:

keySet in interface TByteObjectMap<V>

Returns:

a set view of the keys contained in this map

keys

public byte[] keys()

Returns a copy of the keys of the map as an array. Changes to the array of keys will not be reflected in the map nor vice-versa.

Specified by:

keys in interface TByteObjectMap<V>

Returns:

a copy of the keys of the map as an array.

keys

public byte[] keys(byte[] dest)

Returns a copy of the keys of the map as an array. Changes to the array of keys will not be reflected in the map nor vice-versa.

Specified by:

keys in interface TByteObjectMap<V>

Parameters:

dest - 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:

the keys of the map as an array.

valueCollection

public java.util.Collection<V> valueCollection()

Returns a Collection view of the values contained in this map. The collection is backed by the map, so changes to the map are reflected in the collection, and vice-versa. If the map is modified while an iteration over the collection is in progress (except through the iterator's own remove operation), the results of the iteration are undefined. The collection supports element removal, which removes the corresponding mapping from the map, via the Iterator.remove, Collection.remove, removeAll, retainAll and clear operations. It does not support the add or addAll operations.

Specified by:

valueCollection in interface TByteObjectMap<V>

Returns:

a collection view of the values contained in this map

values

public java.lang.Object[] values()

Returns the values of the map as an Object array. Note that the array returned is typed as an Object[] and may not be cast to a more specific type. See TByteObjectMap.values(Object[]) for a version which allows specifically typed arrays. Changes to the array of values will not be reflected in the map nor vice-versa.

Specified by:

values in interface TByteObjectMap<V>

Returns:

the values of the map as an array of byte values.

values

public V[] values(V[] dest)

Returns the values of the map using an existing array. Changes to the array of values will not be reflected in the map nor vice-versa.

Specified by:

values in interface TByteObjectMap<V>

Parameters:

dest - 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:

the values of the map as an array of byte values.

iterator

public TByteObjectIterator<V> iterator()

Returns a TByteObjectIterator with access to this map's keys and values.

Specified by:

iterator in interface TByteObjectMap<V>

Returns:

a TByteObjectIterator with access to this map's keys and values.

forEachKey

public boolean forEachKey(TByteProcedure procedure)

Executes procedure for each key in the map.

Specified by:

forEachKey in interface TByteObjectMap<V>

Parameters:

procedure - a TObjectProcedure value

Returns:

false if the loop over the keys terminated because the procedure returned false for some key.

forEachValue

public boolean forEachValue(TObjectProcedure<? super V> procedure)

Executes procedure for each value in the map.

Specified by:

forEachValue in interface TByteObjectMap<V>

Parameters:

procedure - a TObjectProcedure value

Returns:

false if the loop over the values terminated because the procedure returned false for some value.

forEachEntry

public boolean forEachEntry(TByteObjectProcedure<? super V> procedure)

Executes procedure for each key/value entry in the map.

Specified by:

forEachEntry in interface TByteObjectMap<V>

Parameters:

procedure - a TByteObjectProcedure value

Returns:

false if the loop over the entries terminated because the procedure returned false for some entry.

retainEntries

public boolean retainEntries(TByteObjectProcedure<? super V> procedure)

Retains only those entries in the map for which the procedure returns a true value.

Specified by:

retainEntries in interface TByteObjectMap<V>

Parameters:

procedure - determines which entries to keep

Returns:

true if the map was modified.

transformValues

public void transformValues(TObjectFunction<V,V> function)

Transform the values in this map using function.

Specified by:

transformValues in interface TByteObjectMap<V>

Parameters:

function - a TObjectFunction value

equals

public boolean equals(java.lang.Object other)

Compares the specified object with this map for equality. Returns true if the given object is also a map and the two maps represent the same mappings. More formally, two maps m1 and m2 represent the same mappings if m1.entrySet().equals(m2.entrySet()). This ensures that the equals method works properly across different implementations of the Map interface.

Specified by:

equals in interface TByteObjectMap<V>

Overrides:

equals in class java.lang.Object

Parameters:

other - object to be compared for equality with this map

Returns:

true if the specified object is equal to this map

hashCode

public int hashCode()

Returns the hash code value for this map. The hash code of a map is defined to be the sum of the hash codes of each entry in the map's entrySet() view. This ensures that m1.equals(m2) implies that m1.hashCode()==m2.hashCode() for any two maps m1 and m2, as required by the general contract of Object.hashCode().

Specified by:

hashCode in interface TByteObjectMap<V>

Overrides:

hashCode in class java.lang.Object

Returns:

the hash code value for this map

See Also:

Object.equals(Object), TByteObjectMap.equals(Object)

writeExternal

public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException

Specified by:

writeExternal in interface java.io.Externalizable

Overrides:

writeExternal in class THash

Throws:

java.io.IOException

readExternal

public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException,
                         java.lang.ClassNotFoundException

Specified by:

readExternal in interface java.io.Externalizable

Overrides:

readExternal in class THash

Throws:

java.io.IOException

java.lang.ClassNotFoundException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object