template<typename KeyType, typename ValueType, class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
class juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >
Holds a set of mappings between some key/value pairs.
The types of the key and value objects are set as template parameters. You can also specify a class to supply a hash function that converts a key value into an hashed integer. This class must have the form:
struct MyHashGenerator
{
int generateHash (MyKeyType
key,
int upperLimit)
const
{
return someFunctionOfMyKeyType (
key) % upperLimit;
}
};
Like the Array class, the key and value types are expected to be copy-by-value types, so if you define them to be pointer types, this class won't delete the objects that they point to.
If you don't supply a class for the HashFunctionType template parameter, the default one provides some simple mappings for strings and ints.
HashMap<int, String> hash;
hash.set (1, "item1");
hash.set (2, "item2");
DBG (i.getKey() <<
" -> " << i.getValue());
- Template Parameters
-
| HashFunctionType | The class of hash function, which must be copy-constructible. |
- See also
- CriticalSection, DefaultHashFunctions, NamedValueSet, SortedSet
@tags{Core}
template<typename KeyType , typename ValueType , class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
Creates an empty hash-map.
- Parameters
-
| numberOfSlots | Specifies the number of hash entries the map will use. This will be the "upperLimit" parameter that is passed to your generateHash() function. The number of hash slots will grow automatically if necessary, or it can be remapped manually using remapTable(). |
| hashFunction | An instance of HashFunctionType, which will be copied and stored to use with the HashMap. This parameter can be omitted if HashFunctionType has a default constructor. |
References juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::hashSlots.
template<typename KeyType , typename ValueType , class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
Removes all values from the map.
Note that this will clear the content, but won't affect the number of slots (see remapTable and getNumSlots).
References juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getLock(), juce::gl::h, juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::hashSlots, and juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::totalNumItems.
Referenced by juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::~HashMap().
template<typename KeyType , typename ValueType , class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
Returns the CriticalSection that locks this structure.
To lock, you can call getLock().enter() and getLock().exit(), or preferably use an object of ScopedLockType as an RAII lock for it.
References juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::lock.
Referenced by juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::clear(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::contains(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::containsValue(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getReference(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::operator[](), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::remapTable(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::remove(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::removeValue(), and juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::swapWith().
template<typename KeyType , typename ValueType , class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
Returns the number of slots which are available for hashing.
Each slot corresponds to a single hash-code, and each one can contain multiple items.
- See also
- getNumSlots()
References juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::hashSlots.
Referenced by juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::containsValue(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getReference(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getSlot(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::Iterator::next(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::remapTable(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::remove(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::removeValue(), and juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::Iterator::resetToEnd().
template<typename KeyType , typename ValueType , class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
Returns a reference to the value corresponding to a given key.
If the map doesn't contain the key, a default instance of the value type is added to the map and a reference to this is returned.
- Parameters
-
| keyToLookFor | the key of the item being requested |
References juce::gl::entry, juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::generateHashFor(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getEntry(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getLock(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getNumSlots(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::hashSlots, juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::remapTable(), and juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::totalNumItems.
Referenced by juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::set().
template<typename KeyType , typename ValueType , class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
Returns the value corresponding to a given key.
If the map doesn't contain the key, a default instance of the value type is returned.
- Parameters
-
| keyToLookFor | the key of the item being requested |
References juce::gl::entry, juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getEntry(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getLock(), and juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getSlot().
template<typename KeyType , typename ValueType , class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
Remaps the hash-map to use a different number of slots for its hash function.
Each slot corresponds to a single hash-code, and each one can contain multiple items.
- See also
- getNumSlots()
References juce::gl::entry, juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::generateHashFor(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getLock(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getNumSlots(), juce::Array< ElementType, TypeOfCriticalSectionToUse, minimumAllocatedSize >::getUnchecked(), juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::hashSlots, juce::Array< ElementType, TypeOfCriticalSectionToUse, minimumAllocatedSize >::insertMultiple(), and juce::Array< ElementType, TypeOfCriticalSectionToUse, minimumAllocatedSize >::set().
Referenced by juce::HashMap< KeyType, ValueType, HashFunctionType, TypeOfCriticalSectionToUse >::getReference().
template<typename KeyType , typename ValueType , class HashFunctionType = DefaultHashFunctions, class TypeOfCriticalSectionToUse = DummyCriticalSection>
1.8.17