} // parseAllJoinItems()
// this method will be documented based on this example itemToken: FOO f
// INNER JOIN BAR b ON f.id = b.id
private FromItem parseJoinItem(FromItem leftFromItem, String itemToken, HashSet <FromItem> fromItems)
{
int indexOfJoin = itemToken.ToUpper().IndexOf(" JOIN ");
// firstPart = "FOO f INNER"
String firstPart = itemToken.Substring(0, indexOfJoin).Trim();
// secondPart = "BAR b ON f.id = b.id"
String secondPart = itemToken.Substring(indexOfJoin + " JOIN ".Length).Trim();
int indexOfJoinType = firstPart.LastIndexOf(" ");
// joinTypeString = "INNER"
String joinTypeString = firstPart.Substring(indexOfJoinType).Trim().ToUpper();
JoinType joinType = (JoinType)Enum.Parse(typeof(JoinType), joinTypeString);
// firstTableToken = "FOO f"
String firstTableToken = firstPart.Substring(0, indexOfJoinType).Trim();
int indexOfOn = secondPart.ToUpper().IndexOf(" ON ");
// secondTableToken = "BAR b"
String secondTableToken = secondPart.Substring(0, indexOfOn).Trim();
FromItem leftSide = parseTableItem(firstTableToken);
FromItem rightSide = parseTableItem(secondTableToken);
fromItems.Add(leftSide);
fromItems.Add(rightSide);
// onClausess = ["f.id = b.id"]
String[] separators = { " AND " };
String[] onClauses = secondPart.Substring(indexOfOn + " ON ".Length).Split(separators, StringSplitOptions.RemoveEmptyEntries);
SelectItem[] leftOn = new SelectItem[onClauses.Length];
SelectItem[] rightOn = new SelectItem[onClauses.Length];
for (int i = 0; i < onClauses.Length; i++)
{
String onClause = onClauses[i];
int indexOfEquals = onClause.IndexOf("=");
// leftPart = "f.id"
String leftPart = onClause.Substring(0, indexOfEquals).Trim();
// rightPart = "b.id"
String rightPart = onClause.Substring(indexOfEquals + 1).Trim();
FromItem[] items = new FromItem[fromItems.Count];
fromItems.CopyTo(items);
leftOn[i] = findSelectItem(leftPart, items);
rightOn[i] = findSelectItem(rightPart, items);
}
FromItem leftItem = (leftFromItem != null) ? leftFromItem : leftSide;
FromItem result = new FromItem(joinType, leftItem, rightSide, leftOn, rightOn);
result.setQuery(_query);
return(result);
} // parseJoinItem()
} // parse()
private FromItem parseTableItem(String itemToken)
{
// From token can be starting with [
String tableNameToken;
String aliasToken;
char startDelimiter = itemToken.Trim()[0];
if (delimiterMap.ContainsKey(startDelimiter))
{
char endDelimiter = delimiterMap[startDelimiter];
int endIndex = itemToken.Trim().LastIndexOf(endDelimiter, itemToken.Trim().Length);
if (endIndex <= 0)
{
throw new QueryParserException("Not capable of parsing FROM token: " + itemToken + ". Expected end "
+ endDelimiter);
}
tableNameToken = itemToken.Trim().Substring(1, endIndex).Trim();
if (itemToken.Trim().Substring(1 + endIndex).Trim().Equals("", StringComparison.CurrentCultureIgnoreCase))
{
/*
* As per code in FromClause Method: getItemByReference(FromItem
* item, String reference) if (alias == null && table != null &&
* reference.equals(table.getName())) { Either we have to change
* the code to add alias.equals("") there or return null here.
*/
aliasToken = null;
}
else
{
aliasToken = itemToken.Trim().Substring(1 + endIndex).Trim();
}
}
else
{
// Default assumption is space being delimiter for tablename and
// alias.. If otherwise use DoubleQuotes or [] around tableName
String[] tokens = itemToken.Split(' ');
tableNameToken = tokens[0];
if (tokens.Length == 2)
{
aliasToken = tokens[1];
}
else if (tokens.Length == 1)
{
aliasToken = null;
}
else
{
throw new QueryParserException("Not capable of parsing FROM token: " + itemToken);
}
}
Table table = _dataContext.getTableByQualifiedLabel(tableNameToken);
if (table == null)
{
throw new QueryParserException("Not capable of parsing FROM token: " + itemToken);
}
FromItem result = new FromItem(table);
result.setAlias(aliasToken);
result.setQuery(_query);
return(result);
} // parseTableItem()
