private void addEmptyRow(Table nestedTable, HNode hNode) {
HTable headersNestedTable = hNode.getNestedTable();
Row emptyRow = nestedTable.addRow(getFactory());
for (HNode nestedHNode : headersNestedTable.getHNodes()) {
if (nestedHNode.hasNestedTable()) {
addEmptyRow(emptyRow.getNode(nestedHNode.getId()).getNestedTable(), nestedHNode);
} else {
emptyRow.setValue(nestedHNode.getId(), "", getFactory());
}
}
}
private void addObjectElement(String key, Object value, HTable headers, Row row)
throws JSONException {
HNode hNode = addHNode(headers, key);
String hNodeId = hNode.getId();
if (value instanceof String) {
if (((String) value).isEmpty() && hNode.hasNestedTable()) {
addEmptyRow(row.getNode(hNodeId).getNestedTable(), hNode);
}
row.setValue(hNodeId, (String) value, getFactory());
} else if (value instanceof Integer) {
row.setValue(hNodeId, value.toString(), getFactory());
} else if (value instanceof Double) {
row.setValue(hNodeId, value.toString(), getFactory());
} else if (value instanceof Long) {
row.setValue(hNodeId, value.toString(), getFactory());
} else if (value instanceof Boolean) {
row.setValue(hNodeId, value.toString(), getFactory());
} else if (value instanceof JSONObject) {
HTable nestedHTable = addNestedHTable(hNode, key, row);
Table nestedTable = row.getNode(hNodeId).getNestedTable();
addKeysAndValues((JSONObject) value, nestedHTable, nestedTable);
} else if (value instanceof JSONArray) {
HTable nestedHTable = addNestedHTable(hNode, key, row);
Table nestedTable = row.getNode(hNodeId).getNestedTable();
JSONArray a = (JSONArray) value;
for (int i = 0; i < a.length(); i++) {
addListElement(a.get(i), nestedHTable, nestedTable);
}
} else if (value == JSONObject.NULL) {
// Ignore
} else {
throw new Error("Cannot handle " + key + ": " + value + " yet.");
}
}
private void addListElement(Object listValue, HTable headers, Table dataTable)
throws JSONException {
if (listValue instanceof JSONObject) {
Row row = dataTable.addRow(getFactory());
JSONObject o = (JSONObject) listValue;
@SuppressWarnings("unchecked")
Iterator<String> it = o.sortedKeys();
while (it.hasNext()) {
String key = it.next();
addObjectElement(key, o.get(key), headers, row);
}
} else if (isPrimitiveValue(listValue)) {
HNode hNode = addHNode(headers, "values");
String hNodeId = hNode.getId();
Row row = dataTable.addRow(getFactory());
// TODO, conserve the types of the primitive types.
String value = "";
if (listValue instanceof String || listValue instanceof Boolean) {
value = (String) listValue;
} else if (listValue instanceof Double) {
value = Double.toString((Double) listValue);
} else if (listValue instanceof Integer) {
value = Integer.toString((Integer) listValue);
} else if (listValue instanceof Long) {
value = Long.toString((Long) listValue);
} else {
// Pedro 2012/09/14
logger.error("Unexpected value in JSON array:" + listValue.toString());
}
row.setValue(hNodeId, value, getFactory());
} else if (listValue instanceof JSONArray) {
HNode hNode = addHNode(headers, "nested array");
String hNodeId = hNode.getId();
Row row = dataTable.addRow(getFactory());
HTable nestedHTable = addNestedHTable(hNode, "nested array values", row);
Table nestedTable = row.getNode(hNodeId).getNestedTable();
JSONArray a = (JSONArray) listValue;
for (int i = 0; i < a.length(); i++) {
addListElement(a.get(i), nestedHTable, nestedTable);
}
} else {
logger.error("Cannot handle whatever case is not covered by the if statements. Sorry.");
}
}
private void generateRDF(
String wkname,
String query,
List<KR2RMLRDFWriter> writers,
R2RMLMappingIdentifier id,
String baseURI)
throws IOException, JSONException, KarmaException, SQLException, ClassNotFoundException {
logger.debug("Generating RDF...");
WorksheetR2RMLJenaModelParser parserTest = new WorksheetR2RMLJenaModelParser(id);
KR2RMLMapping mapping = parserTest.parse();
AbstractJDBCUtil dbUtil = JDBCUtilFactory.getInstance(dbType);
Connection conn = dbUtil.getConnection(hostname, portnumber, username, password, dBorSIDName);
conn.setAutoCommit(false);
java.sql.Statement stmt =
conn.createStatement(
java.sql.ResultSet.TYPE_FORWARD_ONLY, java.sql.ResultSet.CONCUR_READ_ONLY);
stmt.setFetchSize(DATABASE_TABLE_FETCH_SIZE);
ResultSet r = stmt.executeQuery(query);
ResultSetMetaData meta = r.getMetaData();
;
// Get the column names
List<String> columnNames = new ArrayList<>();
for (int i = 1; i <= meta.getColumnCount(); i++) {
columnNames.add(meta.getColumnName(i));
}
// Prepare required Karma objects
Workspace workspace = initializeWorkspace();
RepFactory factory = workspace.getFactory();
Worksheet wk = factory.createWorksheet(wkname, workspace, encoding);
List<String> headersList = addHeaders(wk, columnNames, factory);
int counter = 0;
ArrayList<String> rowValues = null;
while ((rowValues = dbUtil.parseResultSetRow(r)) != null) {
// Generate RDF and create a new worksheet for every DATABASE_TABLE_FETCH_SIZE rows
if (counter % DATABASE_TABLE_FETCH_SIZE == 0 && counter != 0) {
generateRDFFromWorksheet(wk, workspace, mapping, writers, baseURI);
logger.debug("Done for " + counter + " rows ...");
removeWorkspace(workspace);
parserTest = new WorksheetR2RMLJenaModelParser(id);
mapping = parserTest.parse();
workspace = initializeWorkspace();
factory = workspace.getFactory();
wk = factory.createWorksheet(wkname, workspace, encoding);
headersList = addHeaders(wk, columnNames, factory);
}
/** Add the data * */
Table dataTable = wk.getDataTable();
Row row = dataTable.addRow(factory);
for (int i = 0; i < rowValues.size(); i++) {
row.setValue(headersList.get(i), rowValues.get(i), factory);
}
counter++;
}
generateRDFFromWorksheet(wk, workspace, mapping, writers, baseURI);
// Releasing all the resources
r.close();
conn.close();
stmt.close();
logger.debug("done");
}