question: private static Map < String , DimensionField > buildNameToDimensionField ( @ NotNull Set < DimensionField > dimensionFields ) { Map < String , DimensionField > nameToDimensionField = new HashMap < > ( dimensionFields . size ( ) ) ; for ( DimensionField dimensionField : dimensionFields ) { nameToDimensionField . put ( dimensionField . getName ( ) , dimensionField ) ; } return nameToDimensionField ; }
target:  Make a map of dimension field name to dimension field for fast lookups.