DataType#getMaxSize() returns 0 for fixed-length fields, so if we use the setMaxLength() method of ColumnBuilder when creating a fixed-length field we get
java.lang.IllegalArgumentException: invalid fixed length size
because the length we've assigned (0) is smaller than the getFixedSize() (>0) for that DataType.
ref:
Fixed in trunk, will be in the 2.0.9 release.