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package myHbase;import java.io.IOException;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.HBaseConfiguration;import org.apache.hadoop.hbase.HColumnDescriptor;import org.apache.hadoop.hbase.HTableDescriptor;import org.apache.hadoop.hbase.TableName;import org.apache.hadoop.hbase.client.Delete;import org.apache.hadoop.hbase.client.Get;import org.apache.hadoop.hbase.client.HBaseAdmin;import org.apache.hadoop.hbase.client.HTable;import org.apache.hadoop.hbase.client.Put;import org.apache.hadoop.hbase.client.Result;import org.apache.hadoop.hbase.client.ResultScanner;import org.apache.hadoop.hbase.client.Scan;import org.apache.hadoop.hbase.filter.Filter;import org.apache.hadoop.hbase.util.Bytes;public class HBaseDAO { static Configuration conf = HBaseConfiguration.create(); /** * create a table :table_name(columnFamily) * @param tablename * @param columnFamily * @throws Exception */ public static void createTable(String tablename, String columnFamily) throws Exception { HBaseAdmin admin = new HBaseAdmin(conf); if(admin.tableExists(tablename)) { System.out.println("Table exists!"); System.exit(0); } else { HTableDescriptor tableDesc = new HTableDescriptor(TableName.valueOf(tablename)); tableDesc.addFamily(new HColumnDescriptor(columnFamily)); admin.createTable(tableDesc); System.out.println("create table success!"); } admin.close(); } /** * delete table ,caution!!!!!! ,dangerous!!!!!! * @param tablename * @return * @throws IOException */ public static boolean deleteTable(String tablename) throws IOException { HBaseAdmin admin = new HBaseAdmin(conf); if(admin.tableExists(tablename)) { try { admin.disableTable(tablename); admin.deleteTable(tablename); } catch (Exception e) { // TODO: handle exception e.printStackTrace(); admin.close(); return false; } } admin.close(); return true; } /** * put a cell data into a row identified by rowKey,columnFamily,identifier * @param HTable, create by : HTable table = new HTable(conf, "tablename") * @param rowKey * @param columnFamily * @param identifier * @param data * @throws Exception */ public static void putCell(HTable table, String rowKey, String columnFamily, String identifier, String data) throws Exception{ Put p1 = new Put(Bytes.toBytes(rowKey)); p1.add(Bytes.toBytes(columnFamily), Bytes.toBytes(identifier), Bytes.toBytes(data)); table.put(p1); System.out.println("put '"+rowKey+"', '"+columnFamily+":"+identifier+"', '"+data+"'"); } /** * get a row identified by rowkey * @param HTable, create by : HTable table = new HTable(conf, "tablename") * @param rowKey * @throws Exception */ public static Result getRow(HTable table, String rowKey) throws Exception { Get get = new Get(Bytes.toBytes(rowKey)); Result result = table.get(get); System.out.println("Get: "+result); return result; } /** * delete a row identified by rowkey * @param HTable, create by : HTable table = new HTable(conf, "tablename") * @param rowKey * @throws Exception */ public static void deleteRow(HTable table, String rowKey) throws Exception { Delete delete = new Delete(Bytes.toBytes(rowKey)); table.delete(delete); System.out.println("Delete row: "+rowKey); } /** * return all row from a table * @param HTable, create by : HTable table = new HTable(conf, "tablename") * @throws Exception */ public static ResultScanner scanAll(HTable table) throws Exception { Scan s =new Scan(); ResultScanner rs = table.getScanner(s); return rs; } /** * return a range of rows specified by startrow and endrow * @param HTable, create by : HTable table = new HTable(conf, "tablename") * @param startrow * @param endrow * @throws Exception */ public static ResultScanner scanRange(HTable table,String startrow,String endrow) throws Exception { Scan s =new Scan(Bytes.toBytes(startrow),Bytes.toBytes(endrow)); ResultScanner rs = table.getScanner(s); return rs; } /** * return a range of rows filtered by specified condition * @param HTable, create by : HTable table = new HTable(conf, "tablename") * @param startrow * @param filter * @throws Exception */ public static ResultScanner scanFilter(HTable table,String startrow, Filter filter) throws Exception { Scan s =new Scan(Bytes.toBytes(startrow),filter); ResultScanner rs = table.getScanner(s); return rs; } public static void main(String[] args) throws Exception { // TODO Auto-generated method stub HTable table = new HTable(conf, "apitable"); // ResultScanner rs = HBaseDAO.scanRange(table, "2013-07-10*", "2013-07-11*");// ResultScanner rs = HBaseDAO.scanRange(table, "100001", "100003"); ResultScanner rs = HBaseDAO.scanAll(table); for(Result r:rs) { System.out.println("Scan: "+r); } table.close(); // HBaseDAO.createTable("apitable", "testcf");// HBaseDAO.putRow("apitable", "100001", "testcf", "name", "liyang");// HBaseDAO.putRow("apitable", "100003", "testcf", "name", "leon");// HBaseDAO.deleteRow("apitable", "100002");// HBaseDAO.getRow("apitable", "100003");// HBaseDAO.deleteTable("apitable"); }}