com.yworks.yfiles.graph

Interface IMapper<K,V>

Type Parameters:

K - The type of element this interface accepts as keys for the mapping.

V - The type of element this interface accepts as values for the mapping.

All Known Implementing Classes:

CreationProperties, Mapper

public interface IMapper<K,V>

An interface for simple typed dictionary-like implementations.

IMappers are most prominently used when interfacing with layout algorithms and GraphML. IGraph also provides the MapperRegistry to add additional information to a graph.

Using IMapper is described in the section Associating Data with Graph Elements.

See Also:

Mappers, Mapper

Method Summary

Modifier and Type	Method and Description
static <K,V> IMapper<K,V>	fromConstant(V constant) Creates a constant mapper that will always return the constant.
static <K,V> IMapper<K,V>	fromFunction(Function<K,V> getter) Create an implementation of IMapper that delegates getValue(java.lang.Object) getter calls to the provided handler.
V	getValue(K key) Gets the value for a given key in the mapping.
void	setValue(K key, V value) Sets the value for a given key in the mapping.

Method Detail

fromConstant

static <K,V> IMapper<K,V> fromConstant(V constant)

Creates a constant mapper that will always return the constant.

Type Parameters:

K - The type of the key to use.

V - The type of the value to use.

Parameters:

constant - The constant to return in getValue(java.lang.Object)

Returns:

A new instance that will always return the same constant.

fromFunction

static <K,V> IMapper<K,V> fromFunction(Function<K,V> getter)

Create an implementation of IMapper that delegates getValue(java.lang.Object) getter calls to the provided handler.

The implementation returned silently ignores calls to the getValue(java.lang.Object) setter.

Type Parameters:

K - The type of the key to use.

V - The type of the value to use.

Parameters:

getter - The delegate to delegate getValue(java.lang.Object) getter calls to.

Returns:

An implementation that delegates to getter.

getValue

V getValue(K key)

Gets the value for a given key in the mapping.

Setting a value for an already existing key overwrites the previous value.

It depends on the specific implementation of the mapper whether a mapping can be removed. If an implementation provides a way to remove a mapping, that should be preferred over setting a null value. For example, Mapper provides the Mapper.removeValue(java.lang.Object) method.

Parameters:

key - The key of the mapping.

Returns:

The value.

See Also:

setValue(java.lang.Object, java.lang.Object)

setValue

void setValue(K key,
              V value)

Sets the value for a given key in the mapping.

Setting a value for an already existing key overwrites the previous value.

It depends on the specific implementation of the mapper whether a mapping can be removed. If an implementation provides a way to remove a mapping, that should be preferred over setting a null value. For example, Mapper provides the Mapper.removeValue(java.lang.Object) method.

Parameters:

key - The key of the mapping.

value - The value.

See Also:

getValue(java.lang.Object)