TObjectHash (GNU Trove for Java API v2.1.0)

java.lang.Object
- gnu.trove.THash
- - gnu.trove.TObjectHash<T>

All Implemented Interfaces:

TObjectHashingStrategy<T>, java.io.Serializable

Direct Known Subclasses:

THashMap, THashSet, TObjectByteHashMap, TObjectDoubleHashMap, TObjectFloatHashMap, TObjectIntHashMap, TObjectLongHashMap, TObjectShortHashMap
```
public abstract class TObjectHash<T>
extends THash
implements TObjectHashingStrategy<T>
```
An open addressed hashing implementation for Object types. Created: Sun Nov 4 08:56:06 2001

Version:

$Id: TObjectHash.java,v 1.27 2009/06/01 22:14:44 robeden Exp $

Author:

Eric D. Friedman

See Also:

Serialized Form

Field Summary

Fields
Modifier and Type	Field	Description
`protected TObjectHashingStrategy<T>`	`_hashingStrategy`	the strategy used to hash objects in this collection.
`protected java.lang.Object[]`	`_set`	the set of Objects
`protected static java.lang.Object`	`FREE`
`protected static java.lang.Object`	`REMOVED`

Fields inherited from class gnu.trove.THash
_autoCompactionFactor, _autoCompactRemovesRemaining, _free, _loadFactor, _maxSize, _size, DEFAULT_INITIAL_CAPACITY, DEFAULT_LOAD_FACTOR

Constructor Summary

Constructors
Constructor	Description
`TObjectHash()`	Creates a new `TObjectHash` instance with the default capacity and load factor.
`TObjectHash(int initialCapacity)`	Creates a new `TObjectHash` instance whose capacity is the next highest prime above `initialCapacity + 1` unless that value is already prime.
`TObjectHash(int initialCapacity, float loadFactor)`	Creates a new `TObjectHash` instance with a prime value at or near the specified capacity and load factor.
`TObjectHash(int initialCapacity, float loadFactor, TObjectHashingStrategy<T> strategy)`	Creates a new `TObjectHash` instance with a prime value at or near the specified capacity and load factor.
`TObjectHash(int initialCapacity, TObjectHashingStrategy<T> strategy)`	Creates a new `TObjectHash` instance whose capacity is the next highest prime above `initialCapacity + 1` unless that value is already prime.
`TObjectHash(TObjectHashingStrategy<T> strategy)`	Creates a new `TObjectHash` instance with the default capacity and load factor and a custom hashing strategy.

Method Summary

All Methods Instance Methods Concrete Methods
Modifier and Type	Method	Description
`protected int`	`capacity()`
`TObjectHash<T>`	`clone()`
`int`	`computeHashCode(T o)`	This is the default implementation of TObjectHashingStrategy: it delegates hashing to the Object's hashCode method.
`boolean`	`contains(java.lang.Object obj)`	Searches the set for `obj`
`boolean`	`equals(T o1, T o2)`	This is the default implementation of TObjectHashingStrategy: it delegates equality comparisons to the first parameter's equals() method.
`boolean`	`forEach(TObjectProcedure<T> procedure)`	Executes `procedure` for each element in the set.
`protected int`	`index(T obj)`	Locates the index of `obj`.
`protected int`	`insertionIndex(T obj)`	Locates the index at which `obj` can be inserted.
`void`	`readExternal(java.io.ObjectInput in)`
`protected void`	`removeAt(int index)`	Delete the record at `index`.
`protected int`	`setUp(int initialCapacity)`	initializes the Object set of this hash table.
`protected void`	`throwObjectContractViolation(java.lang.Object o1, java.lang.Object o2)`	Convenience methods for subclasses to use in throwing exceptions about badly behaved user objects employed as keys.
`void`	`writeExternal(java.io.ObjectOutput out)`

Methods inherited from class java.lang.Object
equals, finalize, getClass, hashCode, notify, notifyAll, toString, wait, wait, wait

Methods inherited from class gnu.trove.THash
calculateGrownCapacity, clear, compact, ensureCapacity, getAutoCompactionFactor, isEmpty, postInsertHook, reenableAutoCompaction, rehash, setAutoCompactionFactor, size, tempDisableAutoCompaction, trimToSize

- Field Detail
  - _set
```
protected transient java.lang.Object[] _set
```
    the set of Objects
  - _hashingStrategy
```
protected TObjectHashingStrategy<T> _hashingStrategy
```
    the strategy used to hash objects in this collection.
  - REMOVED
```
protected static final java.lang.Object REMOVED
```
  - FREE
```
protected static final java.lang.Object FREE
```
- Constructor Detail
  - TObjectHash
```
public TObjectHash()
```
    Creates a new TObjectHash instance with the default capacity and load factor.
  - TObjectHash
```
public TObjectHash(TObjectHashingStrategy<T> strategy)
```
    Creates a new TObjectHash instance with the default capacity and load factor and a custom hashing strategy.
    
    Parameters:
    
    strategy - used to compute hash codes and to compare objects.
  - TObjectHash
```
public TObjectHash(int initialCapacity)
```
    Creates a new TObjectHash instance whose capacity is the next highest prime above initialCapacity + 1 unless that value is already prime.
    
    Parameters:
    
    initialCapacity - an int value
  - TObjectHash
```
public TObjectHash(int initialCapacity,
                   TObjectHashingStrategy<T> strategy)
```
    Creates a new TObjectHash instance whose capacity is the next highest prime above initialCapacity + 1 unless that value is already prime. Uses the specified custom hashing strategy.
    
    Parameters:
    
    initialCapacity - an int value
    
    strategy - used to compute hash codes and to compare objects.
  - TObjectHash
```
public TObjectHash(int initialCapacity,
                   float loadFactor)
```
    Creates a new TObjectHash 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.
  - TObjectHash
```
public TObjectHash(int initialCapacity,
                   float loadFactor,
                   TObjectHashingStrategy<T> strategy)
```
    Creates a new TObjectHash instance with a prime value at or near the specified capacity and load factor. Uses the specified custom hashing strategy.
    
    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 objects.
- Method Detail
  - clone
```
public TObjectHash<T> clone()
```
    Overrides:
    
    clone in class THash
    
    Returns:
    
    a shallow clone of this collection
  - capacity
```
protected int capacity()
```
    Specified by:
    
    capacity in class THash
    
    Returns:
    
    the current physical capacity of the hash table.
  - removeAt
```
protected void removeAt(int index)
```
    Description copied from class: THash
    
    Delete the record at index. Reduces the size of the collection by one.
    
    Overrides:
    
    removeAt in class THash
    
    Parameters:
    
    index - an int value
  - setUp
```
protected int setUp(int initialCapacity)
```
    initializes the Object set of this hash table.
    
    Overrides:
    
    setUp in class THash
    
    Parameters:
    
    initialCapacity - an int value
    
    Returns:
    
    an int value
  - forEach
```
public boolean forEach(TObjectProcedure<T> procedure)
```
    Executes procedure for each element in the set.
    
    Parameters:
    
    procedure - a TObjectProcedure value
    
    Returns:
    
    false if the loop over the set terminated because the procedure returned false for some value.
  - contains
```
public boolean contains(java.lang.Object obj)
```
    Searches the set for obj
    
    Parameters:
    
    obj - an Object value
    
    Returns:
    
    a boolean value
  - index
```
protected int index(T obj)
```
    Locates the index of obj.
    
    Parameters:
    
    obj - an Object value
    
    Returns:
    
    the index of obj or -1 if it isn't in the set.
  - insertionIndex
```
protected int insertionIndex(T obj)
```
    Locates the index at which obj can be inserted. if there is already a value equal()ing obj in the set, returns that value's index as -index - 1.
    
    Parameters:
    
    obj - an Object value
    
    Returns:
    
    the index of a FREE slot at which obj can be inserted or, if obj is already stored in the hash, the negative value of that index, minus 1: -index -1.
  - computeHashCode
```
public final int computeHashCode(T o)
```
    This is the default implementation of TObjectHashingStrategy: it delegates hashing to the Object's hashCode method.
    
    Specified by:
    
    computeHashCode in interface TObjectHashingStrategy<T>
    
    Parameters:
    
    o - for which the hashcode is to be computed
    
    Returns:
    
    the hashCode
    
    See Also:
    
    Object.hashCode()
  - equals
```
public final boolean equals(T o1,
                            T o2)
```
    This is the default implementation of TObjectHashingStrategy: it delegates equality comparisons to the first parameter's equals() method.
    
    Specified by:
    
    equals in interface TObjectHashingStrategy<T>
    
    Parameters:
    
    o1 - an Object value
    
    o2 - an Object value
    
    Returns:
    
    true if the objects are equal
    
    See Also:
    
    Object.equals(Object)
  - throwObjectContractViolation
```
protected final void throwObjectContractViolation(java.lang.Object o1,
                                                  java.lang.Object o2)
                                           throws java.lang.IllegalArgumentException
```
    Convenience methods for subclasses to use in throwing exceptions about badly behaved user objects employed as keys. We have to throw an IllegalArgumentException with a rather verbose message telling the user that they need to fix their object implementation to conform to the general contract for java.lang.Object.
    
    Parameters:
    
    o1 - the first of the equal elements with unequal hash codes.
    
    o2 - the second of the equal elements with unequal hash codes.
    
    Throws:
    
    java.lang.IllegalArgumentException - the whole point of this method.
  - writeExternal
```
public void writeExternal(java.io.ObjectOutput out)
                   throws java.io.IOException
```
    Overrides:
    
    writeExternal in class THash
    
    Throws:
    
    java.io.IOException
  - readExternal
```
public void readExternal(java.io.ObjectInput in)
                  throws java.io.IOException,
                         java.lang.ClassNotFoundException
```
    Overrides:
    
    readExternal in class THash
    
    Throws:
    
    java.io.IOException
    
    java.lang.ClassNotFoundException

Class TObjectHash<T>

Field Summary

Fields inherited from class gnu.trove.THash

Constructor Summary

Method Summary

Methods inherited from class java.lang.Object

Methods inherited from class gnu.trove.THash

Field Detail

_set

_hashingStrategy

REMOVED

FREE

Constructor Detail

TObjectHash

TObjectHash

TObjectHash

TObjectHash

TObjectHash

TObjectHash

Method Detail

clone

capacity

removeAt

setUp

forEach

contains

index

insertionIndex

computeHashCode

equals

throwObjectContractViolation

writeExternal

readExternal