删除hbase的region步骤和代码

Posted 2020-08-30 金聂政

1、初始化hbase连接

1 Configuration conf = HbaseCommonsUnit.initConfiguration();
2 Connection conn = ConnectionFactory.createConnection(conf);
3 Table meta_table = conn.getTable(TableName.META_TABLE_NAME);
4 HTable table = new HTable(conf, Bytes.toBytes(tablename)); //HTabel负责跟记录相关的操作如增删改查
5 HBaseAdmin admin = new HBaseAdmin(conf); //HBaseAdmin负责跟表相关的操作如create,drop等

2、删除Hbase表中Region中StartKey为2014000的Region及Meta中Region的元数据

A、先关闭regionserver中的Region
B、删除Region在HDFS上的文件
C、删除Meta表中Region数据记录信息

String startKey = "2014000";
HRegionInfo regionInfo = table.getRegionLocation(startKey).getRegionInfo();
String tableNameDataDir = "/data/default/" + tablename; 
FileSystem fs = FileSystem.get(conf); 
Path rootDir = new Path(conf.get("hbase.rootdir") + tableNameDataDir);
HRegionFileSystem.deleteRegionFromFileSystem(conf, fs, rootDir, regionInfo); 
String regionNameAsString = regionInfo.getRegionNameAsString(); 
ServerName serverName_temp = StrategyImplementUnit.getServerNameByRegionName(regionNameAsString);//获取region的regionServerName 
admin.closeRegion(serverName_temp,regionInfo); 
List list = new ArrayList(); 
Delete d1 = new Delete(regionNameAsString.getBytes()); 
list.add(d1); meta_table.delete(list); meta_table.close();

3、创建一个新的region，其中Startkey为NULL

1 String new_end_key = "2013222";
2 TableName tableName = TableName.valueOf(tablename);
3 HRegionInfo regionInfo = new HRegionInfo(tableName, Bytes.toBytes(""), Bytes.toBytes(new_end_key));
4 HRegionFileSystem.createRegionOnFileSystem(conf, fs, rootDir, regionInfo);
5 
6 Put put = MetaTableAccessor.makePutFromRegionInfo(regionInfo);
7 meta_table.put(put);
8 meta_table.close();

4、关闭hbase的连接

   if ( table != null) {
                try {
                    table.close();
                } catch (IOException e) {
                    e.printStackTrace();
                }
            }