org.geotools.process.function.ProcessFunctionFactory
    gt:BufferFeatureCollection(features, buffer)
    gt:DoubleAddition(input_a, input_b)
    gt:FeatureBuffer(input_a, input_b)
    gt:Intersect(geom1, geom2)
    gt:RasterToVector(band, bounds, inside, nodata, raster)
    gt:Union(geom)
    gt:VectorToRaster(features, bounds, attribute, rasterWidth, rasterHeight, title)
    gt:buffer(buffer, geom1)
    parameter(arg0)
org.geotools.filter.function.DefaultFunctionFactory
    Categorize()
    Collection_Average(expression)
    Collection_Bounds(geometry)
    Collection_Count(expression)
    Collection_Max(value)
    Collection_Median(value)
    Collection_Min(expression)
    Collection_Sum(arg0)
    Collection_Unique(expression)
    Concatenate()
    EqualInterval(arg0, arg1)
    IEEEremainder(dividend, divisor)
    Interpolate()
    Jenks(arg0, arg1)
    PropertyExists(propertyName)
    Quantile(arg0, arg1)
    Recode()
    StandardDeviation(arg0, arg1)
    UniqueInterval(arg0, arg1)
    abs(int)
    abs_2(long)
    abs_3(float)
    abs_4(double)
    acos(value)
    area(geometry)
    asin(value)
    atan(value)
    atan2(x, y)
    between(value, low, high)
    boundary(geometry)
    boundaryDimension(geometry)
    buffer(geometry, distance)
    bufferWithSegments(geometry, distance, numberOfSegments)
    ceil(double)
    centroid(geometry)
    classify(expression, classifier)
    contains(geometry, geometry)
    convert(value, class)
    convexHull(geometry)
    cos(radians)
    crosses(geometry, geoemtry)
    dateFormat(format, date)
    dateParse(format, string)
    difference(geometry, geometry)
    dimension(geometry)
    disjoint(geometry, geometry)
    distance(geometry, geometry)
    double2bool(double)
    endAngle(linestring)
    endPoint(linestring)
    env(variable)
    envelope(geometry)
    equalTo(arg0, arg1)
    equalsExact(geometry, geometry)
    equalsExactTolerance(geometry, geometry, tolarance)
    exp(number)
    exteriorRing(geometry)
    floor(double)
    geomFromWKT(geometry)
    geomLength(geometry)
    geometryType(geometry)
    getGeometryN(geometry, index)
    getX(geometry)
    getY(geometry)
    getZ(arg0)
    greaterEqualThan(arg0, arg1)
    greaterThan(arg0, arg1)
    id()
    if_then_else(boolean, then, else)
    in10(arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9, arg10)
    in2(value, test, test)
    in3(arg0, arg1, arg2, arg3)
    in4(arg0, arg1, arg2, arg3, arg4)
    in5(arg0, arg1, arg2, arg3, arg4, arg5)
    in6(arg0, arg1, arg2, arg3, arg4, arg5, arg6)
    in7(arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7)
    in8(arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8)
    in9(arg0, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8, arg9)
    int2bbool(int)
    int2ddouble(int)
    interiorPoint(geometry)
    interiorRingN(geometry, geometry)
    intersection(geometry, geometry)
    intersects(geometry, geometry)
    isClosed(geometry)
    isEmpty(geometry)
    isLike(string, regex)
    isNull(arg0)
    isRing(geometry)
    isSimple(geometry)
    isValid(geometry)
    isWithinDistance(geometry, geometry, distance)
    isometric(geometry, extrusion)
    length(string)
    lessEqualThan(arg0, arg1)
    lessThan(arg0, arg1)
    log(value)
    max(double, double)
    max_2(long, long)
    max_3(float, float)
    max_4(int, int)
    min(double, double)
    min_2(long, long)
    min_3(float, float)
    min_4(int, int)
    not(arg0)
    notEqualTo(arg0, arg1)
    numGeometries(geometry)
    numInteriorRing(polygon)
    numPoints(geometry)
    numberFormat(string, number)
    numberFormat2(format, number, minus, decimal, seperator)
    offset(geometry, offsetX, offsetY)
    overlaps(geometry, geometr)
    parseBoolean(string)
    parseDouble(string)
    parseInt(string)
    parseLong(string)
    pi()
    pointN(geometry, index)
    pow(base, exponent)
    random()
    relate(geometry, geometry)
    relatePattern(geometry, geometry, pattern)
    rint(double)
    round(float)
    roundDouble(number)
    round_2(double)
    sin(radians)
    sqrt(number)
    startAngle(geometry)
    startPoint(geometry)
    strCapitalize(string)
    strConcat(string, string)
    strEndsWith(string, postfix)
    strEqualsIgnoreCase(string, string)
    strIndexOf(string, string)
    strLastIndexOf(string, string)
    strLength(string)
    strMatches(string, regex)
    strPosition(string, lookup, forward/backToFront)
    strReplace(string, search, replace, all)
    strStartsWith(string, prefix)
    strSubstring(string, beginIndex, endIndex)
    strSubstringStart(string, beginIndex)
    strToLowerCase(string)
    strToUpperCase(string)
    strTrim(string)
    strTrim2(string, leading/trailing/both, character)
    symDifference(geometry, geometry)
    tan(radians)
    toDegrees(radians)
    toRadians(degree)
    toWKT(geometry)
    touches(geometry, geometry)
    union(geometry, geometry)
    vertices(geometry)
    within(geometry, geometry)