Class MBExpression

  • All Implemented Interfaces:
    Expression, Function
    Direct Known Subclasses:
    MBColor, MBDecision, MBFeatureData, MBHeatmap, MBLookup, MBMath, MBRampsScalesCurves, MBString, MBTypes, MBVariableBinding, MBZoom

    public abstract class MBExpression
    extends FunctionImpl
    The value for any layout property, paint property, or filter may be specified as an expression. An expression defines a formula for computing the value of the property using the operators described below: -Mathematical operators for performing arithmetic and other operations on numeric values -Logical operators for manipulating boolean values and making conditional decisions -String operators for manipulating strings -Data operators, providing access to the properties of source features -Camera operators, providing access to the parameters defining the current map view

    Expressions are represented as JSON arrays. The first element of an expression array is a string naming the expression operator, e.g. "*"or "case". Subsequent elements (if any) are the arguments to the expression. Each argument is either a literal value (a string, number, boolean, or null), or another expression array.

    • Field Detail

      • json

        protected final JSONArray json
      • name

        protected final String name
      • colors

        public static final List<String> colors
      • decisions

        public static final List<String> decisions
      • featureData

        public static final List featureData
      • heatMap

        public static final List heatMap
      • lookUp

        public static final List lookUp
      • math

        public static final List math
      • ramps

        public static final List ramps
      • string

        public static final List string
      • types

        public static final List types
      • variableBindings

        public static final List variableBindings
      • zoom

        public static final List zoom
    • Constructor Detail

      • MBExpression

        protected MBExpression​(JSONArray json)
        Please use factory method create(JSONArray)
        json - definition
    • Method Detail

      • getName

        public String getName()
        Description copied from class: FunctionImpl
        Gets the name of this function.
        Specified by:
        getName in interface Function
        getName in class FunctionImpl
        the name of the function.
      • create

        public static MBExpression create​(JSONArray json)
        Factory method used to produce the correct MBExpression subclass for the provided JSONArray.
        json - definition
      • canCreate

        public static boolean canCreate​(String name)
      • getExpression

        public abstract Expression getExpression()
        Determines which expression to use.
      • transformLiteral

        public Expression transformLiteral​(Expression ex)
        A function to evaluate a given parameter as an expression and use the MBStyleTransformer to transform Mapbox tokens into CQL expressions.
        cq; text expression
      • transformExpression

        public static Expression transformExpression​(JSONArray json)
        Creates an MBExpression and calls the associated function.