@Override
  public VectorExpressionDescriptor.Descriptor getDescriptor() {
    VectorExpressionDescriptor.Builder b = new VectorExpressionDescriptor.Builder();
    b.setMode(VectorExpressionDescriptor.Mode.PROJECTION).setNumArguments(1)
        .setArgumentTypes(VectorExpressionDescriptor.ArgumentType.STRING_FAMILY)
        .setInputExpressionTypes(VectorExpressionDescriptor.InputExpressionType.COLUMN);
    return b.build();
  }
Superclass to support vectorized functions that take a string
and return a long, optionally with additional configuration arguments.
Used for cast(string), length(string), etc
ql/src/java/org/apache/hadoop/hive/ql/exec/vector/expressions/FuncStringToLong.java