/**
* Each service invocation might have different columns than other other invocations. This method
* integrates all results into one table. For the invocations that don't have a specific column,
* we put null values in corresponding column.
*/
public static Table union(List<Table> srcTables) {
if (srcTables == null) return null;
Table resultTable = new Table();
String attributeId = "";
List<String> uniqueAttributeIDs = new ArrayList<String>();
List<List<Attribute>> srcAttributes = new ArrayList<List<Attribute>>();
List<List<List<String>>> srcValues = new ArrayList<List<List<String>>>();
List<List<String>> srcRowIds = new ArrayList<List<String>>();
List<Attribute> resultAttributes = new ArrayList<Attribute>();
List<List<String>> resultValues = new ArrayList<List<String>>();
List<String> resultRowIds = new ArrayList<String>();
for (Table t : srcTables) {
srcAttributes.add(t.getHeaders());
srcRowIds.add(t.getRowIds());
srcValues.add(t.getValues());
}
for (int i = 0; i < srcAttributes.size(); i++) {
for (int j = 0; j < srcAttributes.get(i).size(); j++) {
attributeId = srcAttributes.get(i).get(j).getId().toString();
if (uniqueAttributeIDs.indexOf(attributeId) == -1) {
uniqueAttributeIDs.add(attributeId);
resultAttributes.add(srcAttributes.get(i).get(j));
}
}
}
List<Attribute> rawAttributes = null;
List<String> rawAttributeIDs = new ArrayList<String>();
List<String> rawValues = null;
String singleValue = null;
for (int i = 0; i < srcAttributes.size(); i++) {
rawAttributes = srcAttributes.get(i);
rawAttributeIDs.clear();
for (Attribute p : rawAttributes) rawAttributeIDs.add(p.getId());
// logger.debug("table " + i);
for (int j = 0; j < srcValues.get(i).size(); j++) {
List<String> populatedValues = new ArrayList<String>();
rawValues = srcValues.get(i).get(j);
// logger.debug("\t row " + j);
for (int k = 0; k < resultAttributes.size(); k++) {
// logger.debug("\t\t column " + k);
int index = rawAttributeIDs.indexOf(resultAttributes.get(k).getId());
if (index == -1) singleValue = null;
// singleValue = "";
else singleValue = rawValues.get(index);
populatedValues.add(singleValue);
}
if (srcRowIds != null
&& srcRowIds.size() > 0
&& srcRowIds.get(i) != null
&& srcRowIds.get(i).size() > 0
&& srcRowIds.get(i).get(j) != null) resultRowIds.add(srcRowIds.get(i).get(j));
resultValues.add(populatedValues);
}
}
resultTable.setHeaders(resultAttributes);
resultTable.setRowIds(resultRowIds);
resultTable.setValues(resultValues);
return resultTable;
}
