HBase Java API使用操作例子
通过对HBase API的使用，下面例子举例了常见对HBase的操作，如下所示：
package net.csdn.jtlyuan;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.KeyValue;import org.apache.hadoop.hbase.client.HBaseAdmin;import org.apache.hadoop.hbase.client.HTable;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.io.BatchUpdate;public class HBaseDBDao {//定义配置对象HBaseConfigurationstatic HBaseConfiguration cfg =null;static {Configuration configuration = new Configuration();cfg = new HBaseConfiguration(configuration);}//创建一张表，指定表名，列族public static void createTable(String tableName,String columnFarily)throws Exception{HBaseAdmin admin = new HBaseAdmin(cfg);if(admin.tableExists(tableName)){System.out.println(tableName+"不存在！");System.exit(0);}else{HTableDescriptor tableDesc = new HTableDescriptor(tableName);tableDesc.addFamily(new HColumnDescriptor(columnFarily+":"));System.out.println("创建表成功！");}}//添加数据，通过HTable。和BatchUpdate为已经存在的表添加数据datapublic static void addData(String tableName,String row,String columnFamily,String column,String data)throws Exception{HTable table = new HTable(cfg,tableName);BatchUpdate update = new BatchUpdate(row);update.put(columnFamily+":"+column, data.getBytes());table.commit(update);System.out.println("添加成功！");}//显示所有数据，通过HTable Scan类获取已有表的信息public static void getAllData(String tableName)throws Exception{HTable table = new HTable(cfg,tableName);Scan scan = new Scan();ResultScanner rs = table.getScanner(scan);for(Result r:rs){for(KeyValue kv:r.raw()){System.out.println(new String(kv.getColumn())+new String(kv.getValue()));}}}//测试函数public static void main(String[] args){try{String tableName = "student";HBaseDBDao.createTable(tableName, "c1");HBaseDBDao.addData(tableName, "row1", "c1", "1", "this is row 1 column c1:c1");HBaseDBDao.getAllData(tableName);}catch(Exception e){e.printStackTrace();}}}