protected void addFrom()

in empire-db/src/main/java/org/apache/empire/db/DBCommand.java [1825:1895]
58 lines of code
13 McCabe index (conditional complexity)

    protected void addFrom(DBSQLBuilder sql)
    {
        int originalLength = sql.length();
        sql.append("\r\nFROM ");
        // Join
        boolean sep = false;
        // int whichParams = 0;
        List<DBRowSet> tables = getRowSetList();
        if (joins!=null && joins.size()>0)
        {   // Join
            List<DBRowSet> joinTables = new ArrayList<DBRowSet>();
            for (int i=0; i<joins.size(); i++)
            {    // append join
                 long context;
                 DBJoinExpr join = joins.get(i);
                 if (i<1)
                 {   // Add Join Tables
                     joinTables.add(join.getLeftTable());
                     joinTables.add(join.getRightTable());
                     // Remove from List
                     tables.remove(join.getLeftTable());
                     tables.remove(join.getRightTable());
                     // Context
                     context = CTX_NAME|CTX_VALUE;
                     // whichParams = 0;
                 }
                 else
                 {   // Extend the join                    
                     if (joinTables.contains(join.getRightTable()))
                         join.reverse();
                     // Add Right Table     
                     joinTables.add(join.getRightTable());
                     tables .remove(join.getRightTable());
                     // Context
                     context = CTX_VALUE;
                     sql.append( "\t" );
                     // whichParams = 1;
                 }
                 // check
                 join.addSQL(sql, context);
                 // cmdParams.addJoin(sql, join, context, whichParams);
                 // add CRLF
                 if( i!=joins.size()-1 )
                     sql.append("\r\n");
            }
            sep = true;
        }
        for (int i=0; i<tables.size(); i++)
        {
            DBRowSet t = tables.get(i);
            // check whether it's a parent table
            if (this.parentTables!=null && this.parentTables.contains(t))
                continue; // yes, ignore
            // append
            if (sep) sql.append(", ");
            t.addSQL(sql, CTX_DEFAULT|CTX_ALIAS);
            sep = true;
        }
        if (sep==false)
        {   // add pseudo table or omitt from
            String pseudoTable = getDatabase().getDbms().getSQLPhrase(DBSqlPhrase.SQL_PSEUDO_TABLE);
            if (StringUtils.isNotEmpty(pseudoTable))
            {   // add pseudo table
                sql.append(pseudoTable);
            }    
            else
            {   // remove from
                sql.reset(originalLength);
            }
        }
    }