Returns a {@code hashFormatAlias}-to-<code>fullyQualifiedHashFormatClassNameImplementation</code> map.
<p/>
This map will be used by the {@link #getInstance(string) getInstance} implementation: that method's argument
will be used as a lookup key to this map. If the map returns a value, that value will be used to instantiate
and return a new {@code HashFormat} instance.
<h3>Defaults</h3>
Shiro's default HashFormat implementations (as listed by the {@link ProvidedHashFormat} enum) will
be searched automatically independently of this map. You only need to populate this map with custom
{@code HashFormat} implementations that are <em>not</em> already represented by a {@code ProvidedHashFormat}.
<h3>Efficiency</h3>
Populating this map will be more efficient than configuring {@link #getSearchPackages() searchPackages},
but search packages may be more convenient depending on the number of {@code HashFormat} implementations that
need to be supported by this factory.
@return a {@code hashFormatAlias}-to-<code>fullyQualifiedHashFormatClassNameImplementation</code> map.
Returns a {@code hashFormatAlias}-to-<code>fullyQualifiedHashFormatClassNameImplementation</code> map. <p/> This map will be used by the {@link #getInstance(string) getInstance} implementation: that method's argument will be used as a lookup key to this map. If the map returns a value, that value will be used to instantiate and return a new {@code HashFormat} instance. <h3>Defaults</h3> Shiro's default HashFormat implementations (as listed by the {@link ProvidedHashFormat} enum) will be searched automatically independently of this map. You only need to populate this map with custom {@code HashFormat} implementations that are <em>not</em> already represented by a {@code ProvidedHashFormat}. <h3>Efficiency</h3> Populating this map will be more efficient than configuring {@link #getSearchPackages() searchPackages}, but search packages may be more convenient depending on the number of {@code HashFormat} implementations that need to be supported by this factory.
@return a {@code hashFormatAlias}-to-<code>fullyQualifiedHashFormatClassNameImplementation</code> map.