Mycat 实现MongoDB的BETWEEN AND和多IN&NOT IN查询
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在实现过程中第一就是分析怎么去实现，其次在mycat哪个部分实现。首先我们知道BETWEEN AND是一个区间值查询，而IN 是一个多值且的关系，其实最终目的都是封装为MongoDB支持的数据库操作语句，如：db.getCollection('t_alarm_aggr_20170822').find({ "F_START_TIME" : { "$gte" : "2017-08-21 00:00:00" , "$lte" : "2017-08-23 23:55:00"} , "F_ID" : { "$in" : [5000000001064]}}); 这样就实现了我们的需求了。
BETWEEN AND查询
主要操作io.mycat.route.util.RouterUtil.java类：
/** * @throws SQLNonTransientException * 解析betweenSQL * @MethodName: parseSQLToChangeBetweenSql * @Description: * @param ctx * @throws */private static void parseSQLToChangeBetweenSql( DruidShardingParseInfo ctx) throws SQLNonTransientException{ if(ctx==null){ return; // 没有上下文:no route to find } String tempStr=new String(ctx.getSql().toString()).replaceAll(" ", "").toUpperCase().trim(); String endSql="";if(tempStr.contains("NOTBETWEEN")){throw new IllegalArgumentException("Not support' WHERE $condition NOT BETWEEN $a AND $b ' sql statement :"+ctx.getSql());}else if(tempStr.contains("BETWEEN")){String sql=ctx.getSql().toUpperCase();String conditions=StringUtil.keepInnerSpaceStr(sql.substring(sql.indexOf("WHERE")+5, sql.length())); String strs[] =conditions.split("AND");String conditionField="";String values[]=new String [2];int index=-1;for (int i = 0; i < strs.length; i++) {if(strs[i].contains("BETWEEN")){String temp=StringUtil.keepInnerSpaceStr(strs[i]);conditionField=temp.split(" ")[0];values[0]=temp.split(" ")[2]+" "+temp.split(" ")[3];values[1]=StringUtil.keepInnerSpaceStr(strs[i+1]);index=i;break;}}Date dates[]=new Date [2];for (int i = 0; i < values.length; i++) {try {dates[i]=DateUtil.parseDate(StringUtil.removeBackquote(values[i]), DateUtil.DEFAULT_DATE_PATTERN); } catch (ParseException e) {throw new SQLNonTransientException("date time format must be:"+DateUtil.DEFAULT_DATE_PATTERN);}}StringBuffer changeSql=new StringBuffer();if(dates[0].getTime()<dates[1].getTime()){changeSql.append(conditionField+" >= "+values[0]).append(" AND ").append(conditionField+" <= "+values[1]);}else{changeSql.append(conditionField+" <= "+values[0]).append(" AND ").append(conditionField+" >= "+values[1]);}String newSql=StringUtil.keepInnerSpaceStr(ctx.getSql().substring(0,sql.indexOf("WHERE")+5));for (int i = 0; i < strs.length; i++) {if(i<index){newSql+=" "+strs[i]+" AND ";}else if(i==index){newSql+=" "+changeSql.toString();}else if(i>index+1){newSql+=" AND "+strs[i];}}ctx.setSql(newSql);}}寻找路由调用：
/** * 多表路由 */public static RouteResultset tryRouteForTables(SchemaConfig schema, DruidShardingParseInfo ctx,RouteCalculateUnit routeUnit, RouteResultset rrs, boolean isSelect, LayerCachePool cachePool)throws SQLNonTransientException {List<String> tables = ctx.getTables();if(schema.isNoSharding()||(tables.size() >= 1&&isNoSharding(schema,tables.get(0)))) {if(Pattern.matches(".*_201\\d{5,5}", tables.get(0))){//支持分表, t_location_20170704这种表，删除结尾的_20170704后再查找路由TableConfig tc=schema.getTables().get( tables.get(0).substring(0, tables.get(0).length()-9));return routeToSingleNode(rrs, tc.getDataNodes().get(0), ctx.getSql());}return routeToSingleNode(rrs, schema.getDataNode(), ctx.getSql());}// 处理BETWEEN AND 查询SQLStatementParser parser = new MySqlStatementParser(ctx.getSql()); SQLStatement statement = parser.parseStatement(); if(statement instanceof SQLSelectStatement){// =======between and query to change SQL=======parseSQLToChangeBetweenSql(ctx);rrs.setStatement(ctx.getSql());}//只有一个表的if(tables.size() == 1) {return RouterUtil.tryRouteForOneTable(schema, ctx, routeUnit, tables.get(0), rrs, isSelect, cachePool);}Set<String> retNodesSet = new HashSet<String>();//每个表对应的路由映射Map<String,Set<String>> tablesRouteMap = new HashMap<String,Set<String>>();//分库解析信息不为空Map<String, Map<String, Set<ColumnRoutePair>>> tablesAndConditions = routeUnit.getTablesAndConditions();if(tablesAndConditions != null && tablesAndConditions.size() > 0) {//为分库表找路由RouterUtil.findRouteWithcConditionsForTables(schema, rrs, tablesAndConditions, tablesRouteMap, ctx.getSql(), cachePool, isSelect);if(rrs.isFinishedRoute()) {return rrs;}}//为全局表和单库表找路由for(String tableName : tables) {TableConfig tableConfig = schema.getTables().get(tableName.toUpperCase());if(tableConfig==null && Pattern.matches(".*_201\\d{5,5}", tableName)){//支持分表, t_location_20170704这种表，支持结尾的_20170704后再查找路由tableConfig=schema.getTables().get(tableName.substring(0, tableName.length()-9));}if(tableConfig == null) {String msg = "can't find table define in schema "+ tableName + " schema:" + schema.getName();LOGGER.warn(msg);throw new SQLNonTransientException(msg);}if(tableConfig.isGlobalTable()) {//全局表if(tablesRouteMap.get(tableName) == null) {tablesRouteMap.put(tableName, new HashSet<String>());}tablesRouteMap.get(tableName).addAll(tableConfig.getDataNodes());} else if(tablesRouteMap.get(tableName) == null) { //余下的表都是单库表tablesRouteMap.put(tableName, new HashSet<String>());tablesRouteMap.get(tableName).addAll(tableConfig.getDataNodes());}}boolean isFirstAdd = true;for(Map.Entry<String, Set<String>> entry : tablesRouteMap.entrySet()) {if(entry.getValue() == null || entry.getValue().size() == 0) {throw new SQLNonTransientException("parent key can't find any valid datanode ");} else {if(isFirstAdd) {retNodesSet.addAll(entry.getValue());isFirstAdd = false;} else {retNodesSet.retainAll(entry.getValue());if(retNodesSet.size() == 0) {//两个表的路由无交集String errMsg = "invalid route in sql, multi tables found but datanode has no intersection "+ " sql:" + ctx.getSql();LOGGER.warn(errMsg);throw new SQLNonTransientException(errMsg);}}}}if(retNodesSet != null && retNodesSet.size() > 0) {String tableName = tables.get(0);TableConfig tableConfig = schema.getTables().get(tableName.toUpperCase());if(tableConfig==null && Pattern.matches(".*_201\\d{5,5}", tableName)){//支持分表, t_location_20170704这种表，支持结尾的_20170704后再查找路由tableConfig=schema.getTables().get(tableName.substring(0, tableName.length()-9));}if(tableConfig.isDistTable()){routeToDistTableNode(tableName,schema, rrs, ctx.getSql(), tablesAndConditions, cachePool, isSelect);return rrs;}if(retNodesSet.size() > 1 && isAllGlobalTable(ctx, schema)) {// mulit routes ,not cache route resultif (isSelect) {rrs.setCacheAble(false);routeToSingleNode(rrs, retNodesSet.iterator().next(), ctx.getSql());}else {//delete 删除全局表的记录routeToMultiNode(isSelect, rrs, retNodesSet, ctx.getSql(),true);}} else {routeToMultiNode(isSelect, rrs, retNodesSet, ctx.getSql());}}return rrs;}关键调用：// 处理BETWEEN AND 查询SQLStatementParser parser = new MySqlStatementParser(ctx.getSql()); SQLStatement statement = parser.parseStatement(); if(statement instanceof SQLSelectStatement){// =======between and query to change SQL=======parseSQLToChangeBetweenSql(ctx);rrs.setStatement(ctx.getSql());}多个WHERE IN 查询
支持多个IN查询，主要操作io.mycat.backend.jdbc.mongodb.MongoSQLParser.java类：
/** * WHERE IN 查询 * @MethodName: parseWhereIn * @Description: * @param expr * @param query * @throws */ private void parseWhereIn(SQLSelectStatement selectStmt,SQLExpr expr,DBObject query ){ if(expr==null){ return; // 没有条件:no where conditions return this } String conditionStr=new String(expr.toString()).replaceAll(" ", "").toUpperCase().trim(); if(conditionStr.contains("NOTIN(")){ throw new IllegalArgumentException("Not support' WHERE $condition NOT IN ' sql statement"); }else if(conditionStr.contains("IN(")){ String sql=new String(selectStmt.getSelect().toString()).toUpperCase(); String conditions=StringUtil.keepInnerSpaceStr(sql.substring(sql.lastIndexOf("WHERE")+5, sql.length())); String manyIns[]=conditions.split("AND "); for (int a = 0; a < manyIns.length; a++) { if(manyIns[a].contains(" IN")){ String filedStr=StringUtil.keepInnerSpaceStr(manyIns[a].substring(0,manyIns[a].lastIndexOf("IN"))); String currentConditions=StringUtil.keepInnerSpaceStr(manyIns[a].substring(manyIns[a].lastIndexOf("(")+1, manyIns[a].lastIndexOf(")"))); String strs[]=filedStr.split(" "); String field=""; for (int i = strs.length-1; i >=0 ; i++) { if(!"".equals(strs[i].trim())){ field=strs[i].trim(); break; } } String [] values=currentConditions.split(","); BasicDBList blist=new BasicDBList(); for (int i = 0; i < values.length; i++) { if(ValidateUtils.Number(values[i].trim())){ blist.add(Long.valueOf(values[i].trim())); }else{ blist.add(values[i].trim()); } } BasicDBObject obj=new BasicDBObject(); obj.put("$in", blist); query.put(field, obj); } } } }支持NOT IN 查询：
/** * WHERE IN 查询 * @MethodName: parseWhereIn * @Description: * @param expr * @param query * @throws */private void parseWhereIn(SQLSelectStatement selectStmt,SQLExpr expr,DBObject query ){if(expr==null){return; // 没有条件:no where conditions return this}String conditionStr=new String(expr.toString()).replaceAll(" ", "").toUpperCase().trim();if(conditionStr.contains("IN(")||conditionStr.contains("NOTIN(")){String sql=new String(selectStmt.getSelect().toString()).toUpperCase();String conditions=StringUtil.keepInnerSpaceStr(sql.substring(sql.lastIndexOf("WHERE")+5, sql.length())); String manyIns[]=conditions.split("AND");for (int a = 0; a < manyIns.length; a++) {String temp=new String(manyIns[a]).trim();if(temp.contains(" IN")&&!temp.contains("NOT IN")){String filedStr=StringUtil.keepInnerSpaceStr(manyIns[a].substring(0,manyIns[a].lastIndexOf(" IN")));String currentConditions=StringUtil.keepInnerSpaceStr(manyIns[a].substring(manyIns[a].lastIndexOf("(")+1, manyIns[a].lastIndexOf(")")));String strs[]=filedStr.split(" ");String field="";for (int i = strs.length-1; i >=0 ; i++) {if(!"".equals(strs[i].trim())){field=strs[i].trim();break;}}String [] values=currentConditions.split(",");BasicDBList blist=new BasicDBList();for (int i = 0; i < values.length; i++) {if(ValidateUtils.Number(values[i].trim())){blist.add(Long.valueOf(values[i].trim()));}else{blist.add(values[i].trim());}}BasicDBObject obj=new BasicDBObject();obj.put("$in", blist);query.put(field, obj);}else if(temp.contains(" IN")&&temp.contains("NOT IN")){String filedStr=StringUtil.keepInnerSpaceStr(manyIns[a].substring(0,manyIns[a].lastIndexOf("NOT IN")));String currentConditions=StringUtil.keepInnerSpaceStr(manyIns[a].substring(manyIns[a].lastIndexOf("(")+1, manyIns[a].lastIndexOf(")")));String strs[]=filedStr.split(" ");String field="";for (int i = strs.length-1; i >=0 ; i++) {if(!"".equals(strs[i].trim())){field=strs[i].trim();break;}}String [] values=currentConditions.split(",");BasicDBList blist=new BasicDBList();for (int i = 0; i < values.length; i++) {if(ValidateUtils.Number(values[i].trim())){blist.add(Long.valueOf(values[i].trim()));}else{blist.add(values[i].trim());}}BasicDBObject obj=new BasicDBObject();obj.put("$nin", blist);query.put(field, obj);}}}}执行查询调用： public MongoData query() throws MongoSQLException, SQLNonTransientException {if (!(statement instanceof SQLSelectStatement)) {// return null;throw new IllegalArgumentException("not a query sql statement");}MongoData mongo = new MongoData();DBCursor c = null;SQLSelectStatement selectStmt = (SQLSelectStatement) statement;SQLSelectQuery sqlSelectQuery = selectStmt.getSelect().getQuery();int icount = 0;if (sqlSelectQuery instanceof MySqlSelectQueryBlock) {MySqlSelectQueryBlock mysqlSelectQuery = (MySqlSelectQueryBlock) selectStmt.getSelect().getQuery();if (mysqlSelectQuery.getFrom() != null) {BasicDBObject fields = new BasicDBObject();// 显示的字段for (SQLSelectItem item : mysqlSelectQuery.getSelectList()) {// System.out.println(item.toString());if (!(item.getExpr() instanceof SQLAllColumnExpr)) {if (item.getExpr() instanceof SQLAggregateExpr) {SQLAggregateExpr expr = (SQLAggregateExpr) item.getExpr();if (expr.getMethodName().equals("COUNT")||expr.getMethodName().equals("SUM")) {icount = 1;mongo.setField(getExprFieldName(expr), Types.BIGINT);}fields.put(getExprFieldName(expr), Integer.valueOf(1));} else {fields.put(getFieldName(item), Integer.valueOf(1));}}}// 表名SQLTableSource table = mysqlSelectQuery.getFrom();DBCollection coll = this._db.getCollection(table.toString());mongo.setTable(table.toString());SQLExpr expr = mysqlSelectQuery.getWhere();DBObject query = parserWhere(expr);// parse where IN query parseWhereIn(selectStmt, expr, query);// parse where IN query SQLSelectGroupByClause groupby = mysqlSelectQuery.getGroupBy();BasicDBObject gbkey = new BasicDBObject();if (groupby != null) {for (SQLExpr gbexpr : groupby.getItems()) {if (gbexpr instanceof SQLIdentifierExpr) {String name = ((SQLIdentifierExpr) gbexpr).getName();gbkey.put(name, Integer.valueOf(1));}}icount = 2;}int limitoff = 0;int limitnum = 0;if (mysqlSelectQuery.getLimit() != null) {limitoff = getSQLExprToInt(mysqlSelectQuery.getLimit().getOffset());limitnum = getSQLExprToInt(mysqlSelectQuery.getLimit().getRowCount());}if (icount == 1) {/***********distinct***********/if(selectStmt.getSelect().toString().toLowerCase().contains("distinct")){DBCursor cursor=coll.find(query);Map<String,DBObject> distinctMap=new HashMap<String,DBObject>();for (DBObject dbObject : cursor) {String key=dbObject.toString().hashCode()+"";if(!distinctMap.containsKey(key)){distinctMap.put(key, dbObject);}}mongo.setCount(distinctMap.size());}else{mongo.setCount(coll.count(query));}/***********distinct***********/mongo.setAggrResult(true);} else if (icount == 2) {BasicDBObject initial = new BasicDBObject();initial.put("num", 0);String reduce = "function (obj, prev) { " + " prev.num++}";mongo.setGrouyBy(coll.group(gbkey, query, initial, reduce));} else {if ((limitoff > 0) || (limitnum > 0)) {c = coll.find(query, fields).skip(limitoff).limit(limitnum);} else {c = coll.find(query, fields);}SQLOrderBy orderby = mysqlSelectQuery.getOrderBy();if (orderby != null) {BasicDBObject order = new BasicDBObject();for (int i = 0; i < orderby.getItems().size(); i++) {SQLSelectOrderByItem orderitem = orderby.getItems().get(i);order.put(orderitem.getExpr().toString(),Integer.valueOf(getSQLExprToAsc(orderitem.getType())));}c.sort(order);// System.out.println(order);}}mongo.setCursor(c);} else {mongo = query2();}}return mongo;}核心调用：
// 表名SQLTableSource table = mysqlSelectQuery.getFrom();DBCollection coll = this._db.getCollection(table.toString());mongo.setTable(table.toString());SQLExpr expr = mysqlSelectQuery.getWhere();DBObject query = parserWhere(expr);// parse where IN query parseWhereIn(selectStmt, expr, query);// parse where IN query
实现分段查询原理
看完下面的内容就明白了：
db.getCollection('t_alarm_aggr_20170822').find({});db.getCollection('t_alarm_aggr_20170822').find({ "F_START_TIME" : { "$gte" : "2017-08-21 00:00:00" , "$lte" : "2017-08-23 23:55:00"}});db.getCollection('t_alarm_aggr_20170822').find({ "F_START_TIME" : { "$gte" : "2017-08-21 00:00:00" , "$lte" : "2017-08-23 23:55:00"} , "F_ID" : { "$in" : [5000000001063,5000000001064]}}).sort({"F_START_TIME":-1,"F_ALARM_ID":-1});注：实际上只要满足mongodb的shell命令就可以了。
测试验证修改效果
BETWEEN AND:
mysql> SELECT F_ID, F_VEHICLE_ID, F_ALARMBAK, F_START_TIME, F_START_ID, F_END_TIME, F_STATUS, F_DSpeed, F_Speed, F_ALARM_ID, F_ENTERPRISE_ID FROM T_ALARM_AGGR WHERE F_START_TIME BETWEEN '2017-08-21 00:00:00' AND '2017-08-23 23:55:00';ERROR 2006 (HY000): MySQL server has gone awayNo connection. Trying to reconnect...Connection id: 108Current database: cvnavidb+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+| F_ID | F_VEHICLE_ID | F_ALARMBAK | F_START_TIME | F_START_ID | F_END_TIME | F_STATUS | F_DSpeed | F_Speed | F_ALARM_ID | F_ENTERPRISE_ID |+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+| 5000000001063 | 4908520417546251 | NULL | 2017-08-21 00:26:00 | 5000000468156 | 2017-08-21 00:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001064 | 4908520417546251 | NULL | 2017-08-21 00:26:01 | 5000000468160 | 2017-08-21 00:26:01 | 0 | NULL | NULL | 49 | NULL || 5000000001063 | 4908520417546251 | NULL | 2017-08-21 10:26:00 | 5000000468156 | 2017-08-21 10:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001063 | 4908520417546251 | NULL | 2017-08-22 00:26:00 | 5000000468156 | 2017-08-22 00:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001064 | 4908520417546251 | NULL | 2017-08-22 00:26:01 | 5000000468160 | 2017-08-22 00:26:01 | 0 | NULL | NULL | 49 | NULL || 5000000001063 | 4908520417546251 | NULL | 2017-08-22 10:26:00 | 5000000468156 | 2017-08-22 10:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001063 | 4908520417546251 | NULL | 2017-08-23 00:26:00 | 5000000468156 | 2017-08-23 00:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001064 | 4908520417546251 | NULL | 2017-08-23 00:26:01 | 5000000830671 | 2017-08-23 00:26:01 | 0 | NULL | NULL | 49 | NULL |+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+8 rows in set (0.25 sec)mysql>
WHERE IN:
mysql> SELECT F_ID, F_VEHICLE_ID, F_ALARMBAK, F_START_TIME, F_START_ID, F_END_TIME, F_STATUS, F_DSpeed, F_Speed, F_ALARM_ID, F_ENTERPRISE_ID FROM T_ALARM_AGGR WHERE F_START_TIME >= '2017-08-21 00:00:00' AND F_START_TIME<='2017-08-23 23:55:00' AND F_ID IN (5000000001064);+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+| F_ID | F_VEHICLE_ID | F_ALARMBAK | F_START_TIME | F_START_ID | F_END_TIME | F_STATUS | F_DSpeed | F_Speed | F_ALARM_ID | F_ENTERPRISE_ID |+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+| 5000000001064 | 4908520417546251 | NULL | 2017-08-22 00:26:01 | 5000000468160 | 2017-08-22 00:26:01 | 0 | NULL | NULL | 49 | NULL || 5000000001064 | 4908520417546251 | NULL | 2017-08-21 00:26:01 | 5000000468160 | 2017-08-21 00:26:01 | 0 | NULL | NULL | 49 | NULL || 5000000001064 | 4908520417546251 | NULL | 2017-08-23 00:26:01 | 5000000830671 | 2017-08-23 00:26:01 | 0 | NULL | NULL | 49 | NULL |+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+3 rows in set (0.00 sec)mysql> SELECT F_ID, F_VEHICLE_ID, F_ALARMBAK, F_START_TIME, F_START_ID, F_END_TIME, F_STATUS, F_DSpeed, F_Speed, F_ALARM_ID, F_ENTERPRISE_ID FROM T_ALARM_AGGR WHERE F_START_TIME >= '2017-08-21 00:00:00' AND F_START_TIME<='2017-08-23 23:55:00' AND F_ID IN (50000000010613,5000000001064);+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+| F_ID | F_VEHICLE_ID | F_ALARMBAK | F_START_TIME | F_START_ID | F_END_TIME | F_STATUS | F_DSpeed | F_Speed | F_ALARM_ID | F_ENTERPRISE_ID |+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+| 5000000001063 | 4908520417546251 | NULL | 2017-08-23 00:26:00 | 5000000468156 | 2017-08-23 00:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001064 | 4908520417546251 | NULL | 2017-08-23 00:26:01 | 5000000830671 | 2017-08-23 00:26:01 | 0 | NULL | NULL | 49 | NULL || 5000000001063 | 4908520417546251 | NULL | 2017-08-22 00:26:00 | 5000000468156 | 2017-08-22 00:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001064 | 4908520417546251 | NULL | 2017-08-22 00:26:01 | 5000000468160 | 2017-08-22 00:26:01 | 0 | NULL | NULL | 49 | NULL || 5000000001063 | 4908520417546251 | NULL | 2017-08-21 00:26:00 | 5000000468156 | 2017-08-21 00:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001063 | 4908520417546251 | NULL | 2017-08-22 10:26:00 | 5000000468156 | 2017-08-22 10:26:00 | 0 | NULL | NULL | 48 | NULL || 5000000001064 | 4908520417546251 | NULL | 2017-08-21 00:26:01 | 5000000468160 | 2017-08-21 00:26:01 | 0 | NULL | NULL | 49 | NULL || 5000000001063 | 4908520417546251 | NULL | 2017-08-21 10:26:00 | 5000000468156 | 2017-08-21 10:26:00 | 0 | NULL | NULL | 48 | NULL |+---------------+------------------+------------+---------------------+---------------+---------------------+----------+----------+---------+------------+-----------------+8 rows in set (0.01 sec)
多个WHERE IN:
注：上面的测试注意验证功能实现，实际开发中肯定有问题需要做更细致的调整。
修改过源码后打包请备份jar包到其他路径并删除原来的jar在进行上传！ 下图是因为没有删除导致修改程序包不起作用：
