Random number generate as UDF.

RandomNumberGenerator.java

public class RandomNumberGenerator {
    @FunctionTemplate(name = "random", scope = FunctionTemplate.FunctionScope.SIMPLE, nulls = FunctionTemplate.NullHandling.NULL_IF_NULL)
    public static class Uniform implements DrillSimpleFunc {
        @Param
        Float8Holder low;
        @Param
        Float8Holder high;

        @Output
        Float8Holder output;

        public void setup() {
        }

        public void eval() {
            java.lang.System.out.printf("into eval\n");
            output.value = com.mapr.drill.RandomHelper.nextUniform(low.value, high.value);
        }
    }
}