Java連接HBase數據庫，操作HBase數據庫

最近學習了下HBase，面向列的數據庫，屬於NoSql範疇。通過編寫Java代碼來連接HBase數據庫。

一、前提

Hadoop+HBase環境已經裝好，然後利用Java HBase API操作HBase的話，最好將虛擬機中的HBase版本對應起來，我們從虛擬機中把HBase文件下載下來，利用Xftp軟件。

二、編寫代碼

將下載下來的HBase文件夾的 lib包下的所有jar包丟進項目 Library 中然後編寫代碼。

public class HBaseDBCon {
	
	 	
	    public static Configuration configuration;
	    public static Connection connection;
	    public static Admin admin;
	    
	  //初始化連接
	   static{
	        configuration  = HBaseConfiguration.create();
	        
	        try{
	            connection = ConnectionFactory.createConnection(configuration);
	            admin = connection.getAdmin();
	        }catch (IOException e){
	            e.printStackTrace();
	        }
	    }
	 
	   public static void main(String[] args) throws Exception{
		    //創建命名空間
	    	createNameSpace("dp");
	    	//創建表
	    	createTable("dp:dept","info","subdept");
	    	//批量添加數據
	    	mulPut("dp:dept");
	    	close();
	    }
	   /**
	    * 創建命名空間
	    * @param ns 命名空間名字
	    * @throws Exception
	    */
	 	public static void createNameSpace(String ns) throws Exception {
	 		admin.createNamespace(NamespaceDescriptor.create(ns).build());
	 	}
	    //批量添加數據
	    public static void mulPut(String tableName) throws IOException {
			Table table = connection.getTable(TableName.valueOf(tableName));
			// 創建一個列表用於存放Put實例
			List<Put> puts = new ArrayList<Put>();
			
			Put put1 = new Put(Bytes.toBytes("0_001"));
			put1.add(Bytes.toBytes("info"), Bytes.toBytes("name"), Bytes.toBytes("internet"));
			put1.add(Bytes.toBytes("subdept"), Bytes.toBytes("1_001"), Bytes.toBytes("develop"));
			put1.add(Bytes.toBytes("subdept"), Bytes.toBytes("1_002"), Bytes.toBytes("test"));
			puts.add(put1);	

			Put put2 = new Put(Bytes.toBytes("1_001"));
			put2.add(Bytes.toBytes("info"), Bytes.toBytes("name"), Bytes.toBytes("develop"));
			put2.add(Bytes.toBytes("info"), Bytes.toBytes("f_pid"), Bytes.toBytes("0_001"));
			put2.add(Bytes.toBytes("subdept"), Bytes.toBytes("2_001"), Bytes.toBytes("develop1"));
			put2.add(Bytes.toBytes("subdept"), Bytes.toBytes("2_002"), Bytes.toBytes("develop2"));
			put2.add(Bytes.toBytes("subdept"), Bytes.toBytes("2_003"), Bytes.toBytes("develop3"));
			puts.add(put2);
			
			table.put(puts);
			table.close();
		}

	    
	    /**
	     * 創建表
	     * @param myTableName  表名
	     * @param colFamily  列簇
	     * @throws IOException
	     */
	    public static void createTable(String myTableName,String[] colFamily) throws IOException {
	 
	        
	        TableName tableName = TableName.valueOf(myTableName);
	        //判斷是否存在該表
	        if(admin.tableExists(tableName)){
	            System.out.println("talbe is exists!");
	        }else {
	            HTableDescriptor hTableDescriptor = new HTableDescriptor(tableName);
	            for(String str:colFamily){
	                HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(str);
	                hTableDescriptor.addFamily(hColumnDescriptor);
	            }
	            admin.createTable(hTableDescriptor);
	        }
	        //close();
	    }
	    /**
	     * 刪除表
	     * @param tableName 表名
	     * @throws IOException
	     */
	    public static void deleteTable(String tableName) throws IOException {
	        TableName tb_name = TableName.valueOf(tableName);
	        if (admin.tableExists(tb_name)) {
	            admin.disableTable(tb_name);
	            admin.deleteTable(tb_name);
	        }
	        //close();
	    }
	 
	    /**
	     * 查看所有表
	     * @throws IOException
	     */
	    public static void listTables() throws IOException {
	    	//
	        HTableDescriptor hTableDescriptors[] = admin.listTables();
	        for(HTableDescriptor hTableDescriptor :hTableDescriptors){
	            System.out.println(hTableDescriptor.getNameAsString());
	        }
	        //close();
	    }
	  
	    
	    /**
	     * 向表中插入數據
	     * @param tableName 表名
	     * @param rowKey 行鍵
	     * @param colFamily 列簇
	     * @param col 指定插入的列名
	     * @param val 指定插入列名的值
	     * @throws IOException
	     */
	    public static void insertRow(String tableName,String rowKey,String colFamily,String col,String val) throws IOException {
	        Table table = connection.getTable(TableName.valueOf(tableName));
	        //利用Put插入數據
	        Put put = new Put(rowKey.getBytes());
	        //獲取列簇並添加值
	        put.addColumn(colFamily.getBytes(), col.getBytes(), val.getBytes());
	        table.put(put);
	        table.close();
	        //close();
	    }
	    /**
	     * 刪除一行數據
	     * @param tableName
	     * @param rowKey
	     * @param colFamily
	     * @param col
	     * @throws IOException
	     */
	    public static void deleteRow(String tableName,String rowKey,String colFamily,String col) throws IOException {
	        Table table = connection.getTable(TableName.valueOf(tableName));
	        Delete delete = new Delete(rowKey.getBytes());
	        //刪除指定列族
	        //delete.addFamily(Bytes.toBytes(colFamily));
	        //刪除指定列
	        //delete.addColumn(Bytes.toBytes(colFamily),Bytes.toBytes(col));
	        table.delete(delete);
	        table.close();
	        //close();
	    }
	    /**
	     * 根據rowkey查找數據
	     * @param tableName 指定表名
	     * @param rowKey 行鍵
	     * @param colFamily 列簇
	     * @param col 列名
	     * @throws IOException
	     */
	    public static void getData(String tableName,String rowKey,String colFamily,String col)throws  IOException{
	        Table table = connection.getTable(TableName.valueOf(tableName));
	        Get get = new Get(rowKey.getBytes());
	        get.addColumn(colFamily.getBytes(),col.getBytes());
	        Result result = table.get(get);
	        showCell(result);
	        table.close();
	        //close();
	    }
	    /**
	     * 輸出
	     * @param result 結果集
	     */
	    public static void showCell(Result result){
	        Cell[] cells = result.rawCells();
	        for(Cell cell:cells){
	            System.out.println("RowName:"+new String(CellUtil.cloneRow(cell))+" ");
	            System.out.println("Timetamp:"+cell.getTimestamp());
	            System.out.println("column Family:"+new String(CellUtil.cloneFamily(cell))+" ");
	            System.out.println("row Name:"+new String(CellUtil.cloneQualifier(cell))+" ");
	            System.out.println("value:"+new String(CellUtil.cloneValue(cell))+" ");
	        }
	    }
	    
	    /**
	     * 關閉連接
	     */
	    public static void close(){
	        try{
	            if(admin != null){
	                admin.close();
	            }
	            if(null != connection){
	                connection.close();
	            }
	        }catch (IOException e){
	            e.printStackTrace();
	        }
	    }
}

然後將下載下來的HBase文件夾中的hbase-site.xml文件放在src目錄下，然後設置一系列參數配置

<configuration>
  <property>
    <name>hbase.rootdir</name>
    <value>hdfs://master:9000/hbase</value>
  </property>
  <property>
    <name>hbase.zookeeper.quorum</name>
    <value>master</value>
  </property>
  <property>
    <name>hbase.zookeeper.property.dataDir</name>
    <value>/home/hbase-1.2.6/data/zookeeper</value>
  </property>
  <property>
    <name>hbase.cluster.distributed</name>
    <value>true</value>
  </property>
</configuration>

直接運行就可以了。