// bundles measure non-null values in getCount()
// so appending a null cannot append a column
throw new IllegalArgumentException("cannot append a null column value");
}
checkBinding(bundle);
BundleField field = null;
if (bundle.getCount() < fields.length) {
field = fields[bundle.getCount()];
} else {
BundleField newFields[] = new BundleField[fields.length + 1];
System.arraycopy(fields, 0, newFields, 0, fields.length);
newFields[newFields.length - 1] = bundle.getFormat().getField(Integer.toString(fields.length));
fields = newFields;
field = fields[fields.length - 1];
}