HBase-1.2.4使用新的Java API操作库常用方法使用

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最近自学HBase编程，发现书上介绍的一些方法在HBase-1.2.4中过时了，因此，使用新的API改了书中的Demo，能够运行成功，使用的HBase是集群模式，代码可以直接在编译器中运行。

使用ConnectionFactory来连接数据库
表名使用特定的类TableName而不是字符串
弃用HAdmin使用Admin，通过Connection获取
启用HTable使用Table，通过Connection获取
Put.add()方法过时，使用Put.addColumn()

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.*;import org.apache.hadoop.hbase.util.Bytes;import java.io.IOException;import java.util.Map;import java.util.NavigableMap;/** * Created by hadoop on 16-11-24. */public class HBaseTestCase {    static Configuration cfg = HBaseConfiguration.create();    //创建一张表，通过Admin HTableDescriptor 来创建    public static void createTable(Connection connection,TableName tableName, String columnFamily)throws Exception{        Admin admin = connection.getAdmin();        if(admin.tableExists(tableName)){            System.out.println("table Exists!");        }else{            HTableDescriptor tableDesc = new HTableDescriptor(tableName);            tableDesc.addFamily(new HColumnDescriptor(columnFamily));            admin.createTable(tableDesc);            System.out.println("create table success!");        }    }    //添加一条数据，通过HTable Put 为已经存在的表来添加数据    public static void put(Connection connection,TableName tableName,String row,String columnFamily,String column,String data)throws Exception{        Table table = connection.getTable(tableName);        Put p1 = new Put(Bytes.toBytes(row));        p1.addColumn(Bytes.toBytes(columnFamily),Bytes.toBytes(column),Bytes.toBytes(data));        table.put(p1);    }    //根据row key获取表中的该行数据    public static void get(Connection connection,TableName tableName,String row)throws IOException {        Table table = connection.getTable(tableName);        Get g = new Get(Bytes.toBytes(row));        Result result = table.get(g);        NavigableMap<byte[], NavigableMap<byte[], NavigableMap<Long, byte[]>>> navigableMap = result.getMap();        for(Map.Entry<byte[], NavigableMap<byte[], NavigableMap<Long, byte[]>>> entry:navigableMap.entrySet()){            System.out.print(Bytes.toString(entry.getKey())+"#");            NavigableMap<byte[], NavigableMap<Long, byte[]>> map =entry.getValue();            for(Map.Entry<byte[], NavigableMap<Long, byte[]>> en:map.entrySet()){                System.out.print(Bytes.toString(en.getKey())+"##");                NavigableMap<Long, byte[]> ma = en.getValue();                for(Map.Entry<Long, byte[]>e: ma.entrySet()){                    System.out.print(e.getKey()+"###");                    System.out.println(Bytes.toString(e.getValue()));                }            }        }       // System.out.println("Get:"+result);    }    //根据TableName获取整张表中的数据    public static void scan(Connection connection,TableName tableName)throws Exception{        Table table = connection.getTable(tableName);        Scan s = new Scan();        ResultScanner rs = table.getScanner(s);        //遍历打印表中的数据        for(Result r:rs){            NavigableMap<byte[], NavigableMap<byte[], NavigableMap<Long, byte[]>>> navigableMap = r.getMap();            for(Map.Entry<byte[], NavigableMap<byte[], NavigableMap<Long, byte[]>>> entry:navigableMap.entrySet()){                System.out.print(Bytes.toString(r.getRow())+":");                System.out.print(Bytes.toString(entry.getKey())+"#");                NavigableMap<byte[], NavigableMap<Long, byte[]>> map =entry.getValue();                for(Map.Entry<byte[], NavigableMap<Long, byte[]>> en:map.entrySet()){                    System.out.print(Bytes.toString(en.getKey())+"##");                    NavigableMap<Long, byte[]> ma = en.getValue();                    for(Map.Entry<Long, byte[]>e: ma.entrySet()){                        System.out.print(e.getKey()+"###");                        System.out.println(Bytes.toString(e.getValue()));                    }                }            }            System.out.println();        }    }    //删除表中的数据    public static boolean delete(Connection connection,TableName tableName) throws IOException{        Admin admin = connection.getAdmin();        if(admin.tableExists(tableName)){            try{                admin.disableTable(tableName);                admin.deleteTable(tableName);            }catch(Exception ex){                ex.printStackTrace();                return false;            }        }        return true;    }    public static void main(String args[]){        TableName tableName = TableName.valueOf("hbase_tb");        String columnFamily = "cf";        try{            cfg.set("hbase.zookeeper.property.clientPort", "2181");            cfg.set("hbase.zookeeper.quorum", "fang-ubuntu,fei-ubuntu,kun-ubuntu");            Connection connection = ConnectionFactory.createConnection(cfg);            HBaseTestCase.createTable(connection,tableName,columnFamily);            HBaseTestCase.put(connection,tableName,"row1",columnFamily,"cl1","data");            HBaseTestCase.put(connection,tableName,"row2",columnFamily,"cl1","fang");            HBaseTestCase.put(connection,tableName,"row2",columnFamily,"cl2","fang");            HBaseTestCase.put(connection,tableName,"row2",columnFamily,"cl3","fang");            HBaseTestCase.put(connection,tableName,"row3",columnFamily,"cl4","fang");            HBaseTestCase.get(connection,tableName,"row1");            HBaseTestCase.scan(connection,tableName);            if(true==HBaseTestCase.delete(connection,tableName)){                System.out.println("Delete table:"+tableName.toString()+" success!");            }        }catch(Exception e){            e.printStackTrace();        }    }}

代码实例中使用到了HBase的基本操作。

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