public TransformerComponentBuilder(
AnalysisJobBuilder analysisJobBuilder,
TransformerDescriptor<T> descriptor,
IdGenerator idGenerator) {
super(analysisJobBuilder, descriptor, TransformerComponentBuilder.class);
_id = "trans-" + idGenerator.nextId();
_idGenerator = idGenerator;
_localChangeListeners = new ArrayList<TransformerChangeListener>(0);
}
/**
* Gets the output column of this transformation with it's current configuration.
*
* @return
*/
public List<MutableInputColumn<?>> getOutputColumns() {
final Component component = getComponentInstanceForQuestioning();
if (component == null) {
// as long as the transformer is not configured, just return an
// empty list
return Collections.emptyList();
}
final Transformer transformer = (Transformer) component;
final OutputColumns outputColumns = transformer.getOutputColumns();
if (outputColumns == null) {
throw new IllegalStateException(
"getOutputColumns() returned null on transformer: " + transformer);
}
boolean changed = false;
// adjust the amount of output columns
final int expectedCols = outputColumns.getColumnCount();
final int existingCols = _outputColumns.size();
if (expectedCols != existingCols) {
changed = true;
int colDiff = expectedCols - existingCols;
if (colDiff > 0) {
for (int i = 0; i < colDiff; i++) {
final int nextIndex = _outputColumns.size();
final String name = getColumnName(outputColumns, nextIndex);
final String id = _id + "-" + _idGenerator.nextId();
_outputColumns.add(new TransformedInputColumn<Object>(name, id));
_automaticOutputColumnNames.add(name);
}
} else if (colDiff < 0) {
for (int i = 0; i < Math.abs(colDiff); i++) {
// remove from the tail
_outputColumns.remove(_outputColumns.size() - 1);
_automaticOutputColumnNames.remove(_automaticOutputColumnNames.size() - 1);
}
}
// reset the names when the number of output columns change and the
// initial name has changed
for (int i = 0; i < expectedCols; i++) {
final MutableInputColumn<?> column = _outputColumns.get(i);
final String previousProposedName = column.getInitialName();
final String newProposedName = outputColumns.getColumnName(i);
if (newProposedName != null && !newProposedName.equals(previousProposedName)) {
column.setName(newProposedName);
}
}
}
// automatically update names and types of columns if they have not been
// manually set
for (int i = 0; i < expectedCols; i++) {
final String proposedName = getColumnName(outputColumns, i);
final Class<?> dataType = outputColumns.getColumnType(i);
final TransformedInputColumn<?> col = (TransformedInputColumn<?>) _outputColumns.get(i);
col.setInitialName(proposedName);
if (dataType != col.getDataType()) {
col.setDataType(dataType);
changed = true;
}
final String automaticName = _automaticOutputColumnNames.get(i);
final String columnName = col.getName();
if (StringUtils.isNullOrEmpty(columnName) || automaticName.equals(columnName)) {
if (proposedName != null) {
col.setName(proposedName);
_automaticOutputColumnNames.set(i, proposedName);
}
}
}
if (changed) {
// notify listeners
onOutputChanged();
}
return Collections.unmodifiableList(_outputColumns);
}