gnu.trove.map.hash
Class TObjectByteHashMap<K>

java.lang.Object
  gnu.trove.impl.hash.THash
      gnu.trove.impl.hash.TObjectHash<K>
          gnu.trove.map.hash.TObjectByteHashMap<K>

All Implemented Interfaces:

TObjectByteMap<K>, java.io.Externalizable, java.io.Serializable

public class TObjectByteHashMap<K>
extends gnu.trove.impl.hash.TObjectHash<K>
implements TObjectByteMap<K>, java.io.Externalizable

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

See Also:

Serialized Form

Nested Class Summary

protected class

TObjectByteHashMap.KeyView a view onto the keys of the map.

Field Summary

protected byte[]	_values the values of the map
protected byte	no_entry_value the value that represents null

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

_set, consumeFreeSlot, FREE, REMOVED

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

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

Constructor Summary

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

TObjectByteHashMap(int initialCapacity)
Creates a new TObjectByteHashMap instance with a prime capacity equal to or greater than initialCapacity and with the default load factor.

TObjectByteHashMap(int initialCapacity, float loadFactor)
Creates a new TObjectByteHashMap instance with a prime capacity equal to or greater than initialCapacity and with the specified load factor.

TObjectByteHashMap(int initialCapacity, float loadFactor, byte noEntryValue)
Creates a new TObjectByteHashMap instance with a prime value at or near the specified capacity and load factor.

TObjectByteHashMap(TObjectByteMap<? extends K> map)
Creates a new TObjectByteHashMap that contains the entries in the map passed to it.

Method Summary

byte	adjustOrPutValue(K key, byte adjust_amount, byte put_amount) Adjusts the primitive value mapped to the key if the key is present in the map.
boolean	adjustValue(K key, byte amount) Adjusts the primitive value mapped to key.
void	clear() Empties the collection.
boolean	containsKey(java.lang.Object key) Returns true if this map contains a mapping for the specified key.
boolean	containsValue(byte val) Returns true if this map maps one or more keys to the specified value.
boolean	equals(java.lang.Object other) Compares this map with another map for equality of their stored entries.
boolean	forEachEntry(TObjectByteProcedure<? super K> procedure) Executes procedure for each key/value entry in the map.
boolean	forEachKey(TObjectProcedure<? super K> procedure) Executes procedure for each key in the map.
boolean	forEachValue(TByteProcedure procedure) Executes procedure for each value in the map.
byte	get(java.lang.Object key) Returns the value to which the specified key is mapped, or null if this map contains no mapping for the key.
byte	getNoEntryValue() Returns the value that will be returned from TObjectByteMap.get(java.lang.Object) or TObjectByteMap.put(K, byte) if no entry exists for a given key.
int	hashCode() Returns the hash code value for this map.
boolean	increment(K key) Increments the primitive value mapped to key by 1
TObjectByteIterator<K>	iterator() Returns a TObjectByteIterator with access to this map's keys and values.
java.lang.Object[]	keys() Returns a copy of the keys of the map as an array.
K[]	keys(K[] a) Returns a copy of the keys of the map as an array.
java.util.Set<K>	keySet() Returns a Set view of the keys contained in this map.
byte	put(K key, byte value) Associates the specified value with the specified key in this map (optional operation).
void	putAll(java.util.Map<? extends K,? extends java.lang.Byte> map) Copies all of the mappings from the specified map to this map (optional operation).
void	putAll(TObjectByteMap<? extends K> map) Put all the entries from the given map into this map.
byte	putIfAbsent(K key, byte 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 map to the new capacity.
byte	remove(java.lang.Object key) Removes the mapping for a key from this map if it is present (optional operation).
protected void	removeAt(int index) Removes the mapping at index from the map.
boolean	retainEntries(TObjectByteProcedure<? super K> procedure) Retains only those entries in the map for which the procedure returns a true value.
int	setUp(int initialCapacity) initializes the hashtable to a prime capacity which is at least initialCapacity + 1.
java.lang.String	toString()
void	transformValues(TByteFunction function) Transform the values in this map using function.
TByteCollection	valueCollection() Returns a TByteCollection view of the values contained in this map.
byte[]	values() Returns the values of the map as an array of byte values.
byte[]	values(byte[] array) Returns the values of the map using an existing array.
void	writeExternal(java.io.ObjectOutput out)

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

buildObjectContractViolation, capacity, contains, dumpExtraInfo, equals, forEach, hash, index, insertionIndex, insertKey, objectInfo, reportPotentialConcurrentMod, throwObjectContractViolation, throwObjectContractViolation

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

calculateGrownCapacity, compact, computeMaxSize, computeNextAutoCompactionAmount, ensureCapacity, getAutoCompactionFactor, isEmpty, postInsertHook, reenableAutoCompaction, 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.TObjectByteMap

isEmpty, size

Field Detail

_values

protected transient byte[] _values

the values of the map

no_entry_value

protected byte no_entry_value

the value that represents null

Constructor Detail

TObjectByteHashMap

public TObjectByteHashMap()

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

TObjectByteHashMap

public TObjectByteHashMap(int initialCapacity)

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

Parameters:

initialCapacity - an int value

TObjectByteHashMap

public TObjectByteHashMap(int initialCapacity,
                          float loadFactor)

Creates a new TObjectByteHashMap 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

TObjectByteHashMap

public TObjectByteHashMap(int initialCapacity,
                          float loadFactor,
                          byte noEntryValue)

Creates a new TObjectByteHashMap 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.

noEntryValue - the value used to represent null.

TObjectByteHashMap

public TObjectByteHashMap(TObjectByteMap<? extends K> map)

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

Parameters:

map - the TObjectByteMap to be copied.

Method Detail

setUp

public int setUp(int initialCapacity)

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

Overrides:

setUp in class gnu.trove.impl.hash.TObjectHash<K>

Parameters:

initialCapacity - an int value

Returns:

the actual capacity chosen

rehash

protected void rehash(int newCapacity)

rehashes the map to the new capacity.

Specified by:

rehash in class gnu.trove.impl.hash.THash

Parameters:

newCapacity - an int value

getNoEntryValue

public byte getNoEntryValue()

Returns the value that will be returned from TObjectByteMap.get(java.lang.Object) or TObjectByteMap.put(K, byte) if no entry exists for a given key. The default value is generally zero, but can be changed during construction of the collection.

Specified by:

getNoEntryValue in interface TObjectByteMap<K>

Returns:

the value that represents a null value in this collection.

containsKey

public boolean containsKey(java.lang.Object 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==null ? k==null : key.equals(k)). (There can be at most one such mapping.)

Specified by:

containsKey in interface TObjectByteMap<K>

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(byte 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==no_entry_value ? v==no_entry_value : value.equals(v)). This operation will probably require time linear in the map size for most implementations of the Map interface.

Note that no_entry_value is the result of TObjectByteMap.getNoEntryValue() and represents null for this map instance.

Specified by:

containsValue in interface TObjectByteMap<K>

Parameters:

val - byte 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 byte get(java.lang.Object 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 TObjectByteMap<K>

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 byte put(K key,
                byte 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 TObjectByteMap<K>

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:

TObjectByteMap.getNoEntryValue()

putIfAbsent

public byte putIfAbsent(K key,
                        byte 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 TObjectByteMap<K>

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 the "no entry" value if none was found (see TObjectByteMap.getNoEntryValue()).

remove

public byte remove(java.lang.Object 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==null ? k==null : 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 TObjectByteMap<K>

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)

Removes the mapping at index from the map. This method is used internally and public mainly because of packaging reasons. Caveat Programmer.

Overrides:

removeAt in class gnu.trove.impl.hash.TObjectHash<K>

Parameters:

index - an int value

putAll

public void putAll(java.util.Map<? extends K,? extends java.lang.Byte> 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 TObjectByteMap<K>

Parameters:

map - mappings to be stored in this map

putAll

public void putAll(TObjectByteMap<? extends K> map)

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

Specified by:

putAll in interface TObjectByteMap<K>

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 TObjectByteMap<K>

Overrides:

clear in class gnu.trove.impl.hash.THash

keySet

public java.util.Set<K> keySet()

Returns a Set 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 TObjectByteMap<K>

Returns:

a set view of the keys contained in this map

keys

public java.lang.Object[] 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 TObjectByteMap<K>

Returns:

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

keys

public K[] keys(K[] a)

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 TObjectByteMap<K>

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:

the keys of the map as an array.

valueCollection

public TByteCollection valueCollection()

Returns a TByteCollection 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 TByteIterator.remove, TByteCollection.remove, removeAll, retainAll and clear operations. It does not support the add or addAll operations.

Specified by:

valueCollection in interface TObjectByteMap<K>

Returns:

a collection view of the values contained in this map

values

public byte[] values()

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

Specified by:

values in interface TObjectByteMap<K>

Returns:

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

values

public byte[] values(byte[] array)

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 TObjectByteMap<K>

Parameters:

array - 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 TObjectByteIterator<K> iterator()

Description copied from interface: TObjectByteMap

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

Specified by:

iterator in interface TObjectByteMap<K>

Returns:

an iterator over the entries in this map

increment

public boolean increment(K key)

Increments the primitive value mapped to key by 1

Specified by:

increment in interface TObjectByteMap<K>

Parameters:

key - the key of the value to increment

Returns:

true if a mapping was found and modified.

adjustValue

public boolean adjustValue(K key,
                           byte amount)

Adjusts the primitive value mapped to key.

Specified by:

adjustValue in interface TObjectByteMap<K>

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.

adjustOrPutValue

public byte adjustOrPutValue(K key,
                             byte adjust_amount,
                             byte 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.

Specified by:

adjustOrPutValue in interface TObjectByteMap<K>

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

forEachKey

public boolean forEachKey(TObjectProcedure<? super K> procedure)

Executes procedure for each key in the map.

Specified by:

forEachKey in interface TObjectByteMap<K>

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(TByteProcedure procedure)

Executes procedure for each value in the map.

Specified by:

forEachValue in interface TObjectByteMap<K>

Parameters:

procedure - a TByteProcedure value

Returns:

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

forEachEntry

public boolean forEachEntry(TObjectByteProcedure<? super K> procedure)

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

Specified by:

forEachEntry in interface TObjectByteMap<K>

Parameters:

procedure - a TOObjectByteProcedure value

Returns:

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

retainEntries

public boolean retainEntries(TObjectByteProcedure<? super K> procedure)

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

Specified by:

retainEntries in interface TObjectByteMap<K>

Parameters:

procedure - determines which entries to keep

Returns:

true if the map was modified.

transformValues

public void transformValues(TByteFunction function)

Transform the values in this map using function.

Specified by:

transformValues in interface TObjectByteMap<K>

Parameters:

function - a TByteFunction value

equals

public boolean equals(java.lang.Object other)

Compares this map with another map for equality of their stored entries.

Specified by:

equals in interface TObjectByteMap<K>

Overrides:

equals in class java.lang.Object

Parameters:

other - an Object value

Returns:

a boolean value

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 TObjectByteMap<K>

Overrides:

hashCode in class java.lang.Object

Returns:

the hash code value for this map

See Also:

Object.equals(Object), TObjectByteMap.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 gnu.trove.impl.hash.TObjectHash<K>

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 gnu.trove.impl.hash.TObjectHash<K>

Throws:

java.io.IOException

java.lang.ClassNotFoundException

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object