Examples with MySQLMessage io.mycat.backend.mysql.MySQLMessage used on opensource projects

Example 56 with MySQLMessage

use of io.mycat.backend.mysql.MySQLMessage in project Mycat-Server by MyCATApache.

the class DataNodeMergeManager method run.

@Override
public void run() {
    if (!running.compareAndSet(false, true)) {
        return;
    }
    boolean nulpack = false;
    try {
        for (; ; ) {
            final PackWraper pack = packs.poll();
            if (pack == null) {
                nulpack = true;
                break;
            }
            if (pack == END_FLAG_PACK) {
                hasEndFlag = true;
                if (packs.peek() != null) {
                    packs.add(pack);
                    continue;
                }
                /**
                 * 最后一个节点datenode发送了row eof packet说明了整个
                 * 分片数据全部接收完成，进而将结果集全部发给你Mycat 客户端
                 */
                final int warningCount = 0;
                final EOFPacket eofp = new EOFPacket();
                final ByteBuffer eof = ByteBuffer.allocate(9);
                BufferUtil.writeUB3(eof, eofp.calcPacketSize());
                eof.put(eofp.packetId);
                eof.put(eofp.fieldCount);
                BufferUtil.writeUB2(eof, warningCount);
                BufferUtil.writeUB2(eof, eofp.status);
                final ServerConnection source = multiQueryHandler.getSession().getSource();
                final byte[] array = eof.array();
                Iterator<UnsafeRow> iters = null;
                if (unsafeRowGrouper != null) {
                    /**
                     * group by里面需要排序情况
                     */
                    if (globalSorter != null) {
                        iters = unsafeRowGrouper.getResult(globalSorter);
                    } else {
                        iters = unsafeRowGrouper.getResult(globalMergeResult);
                    }
                } else if (globalSorter != null) {
                    iters = globalSorter.sort();
                } else if (!isStreamOutputResult) {
                    iters = globalMergeResult.sort();
                }
                if (iters != null) {
                    multiQueryHandler.outputMergeResult(source, array, iters, isMiddleResultDone);
                }
                break;
            }
            unsafeRow = new UnsafeRow(fieldCount);
            bufferHolder = new BufferHolder(unsafeRow, 0);
            unsafeRowWriter = new UnsafeRowWriter(bufferHolder, fieldCount);
            bufferHolder.reset();
            /**
             *构造一行row，将对应的col填充.
             */
            MySQLMessage mm = new MySQLMessage(pack.rowData);
            mm.readUB3();
            mm.read();
            int nullnum = 0;
            for (int i = 0; i < fieldCount; i++) {
                byte[] colValue = mm.readBytesWithLength();
                if (colValue != null)
                    unsafeRowWriter.write(i, colValue);
                else {
                    if (mergeColsIndex != null && mergeColsIndex.length > 0) {
                        if (Arrays.binarySearch(mergeColsIndex, i) < 0) {
                            nullnum++;
                        }
                    }
                    unsafeRow.setNullAt(i);
                }
            }
            if (mergeColsIndex != null && mergeColsIndex.length > 0) {
                if (nullnum == (fieldCount - mergeColsIndex.length)) {
                    if (!hasEndFlag) {
                        packs.add(pack);
                        continue;
                    }
                }
            }
            unsafeRow.setTotalSize(bufferHolder.totalSize());
            if (unsafeRowGrouper != null) {
                unsafeRowGrouper.addRow(unsafeRow);
            } else if (globalSorter != null) {
                globalSorter.insertRow(unsafeRow);
            } else {
                globalMergeResult.insertRow(unsafeRow);
            }
            unsafeRow = null;
            bufferHolder = null;
            unsafeRowWriter = null;
        }
    } catch (final Exception e) {
        e.printStackTrace();
        multiQueryHandler.handleDataProcessException(e);
    } finally {
        running.set(false);
        if (nulpack && !packs.isEmpty()) {
            this.run();
        }
    }
}