為了方便以后查看，總結了一些常用的java操作hbase的代碼：
package com.mcq;import static org.hamcrest.CoreMatchers.describedAs;import static org.hamcrest.CoreMatchers.nullValue;import java.io.IOException;import java.io.PushbackInputStream;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.Cell;import org.apache.hadoop.hbase.CellScannable;import org.apache.hadoop.hbase.CellUtil;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.Admin;import org.apache.hadoop.hbase.client.Connection;import org.apache.hadoop.hbase.client.ConnectionFactory;import org.apache.hadoop.hbase.client.Delete;import org.apache.hadoop.hbase.client.Get;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.client.Table;import org.apache.hadoop.hbase.util.Bytes;public class TestHbase { private static Admin admin = null; private static Connection connection = null; private static Configuration conf = null; static { // HBase組態檔 conf = HBaseConfiguration.create(); conf.set("hbase.zookeeper.quorum", "192.168.1.103"); // 獲取連接物件 try { connection = ConnectionFactory.createConnection(conf); // 獲取HBase管理員物件 admin = connection.getAdmin(); } catch (IOException e) { // TODO Auto-generated catch block e.printStackTrace(); } } private static void close(Connection conn, Admin admin) throws IOException { if (conn != null) { conn.close(); } if (admin != null) { admin.close(); } } // 判斷表是否存在 public static boolean tableExist(String tableName) throws IOException { boolean tableExists = admin.tableExists(TableName.valueOf(tableName)); return tableExists; } // 創建表 public static void createTable(String tableName, String... cfs) throws IOException { if (tableExist(tableName)) { System.out.println("表已存在"); return; } // cfs是列族，官方建議一個表一個，但可以有多個 // 創建表描述器 HTableDescriptor hTableDescriptor = new HTableDescriptor(TableName.valueOf(tableName)); for (String cf : cfs) { // 創建列描述器 HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(cf);// hColumnDescriptor.setMaxVersions(3);//設定版本數 hTableDescriptor.addFamily(hColumnDescriptor); } // 創建表操作 admin.createTable(hTableDescriptor); } // 洗掉表 public static void deleteTable(String tableName) throws IOException { if (!tableExist(tableName)) { System.out.println("表不存在"); return; } // 使表不可用（下線） admin.disableTable(TableName.valueOf(tableName)); // 執行洗掉操作 admin.deleteTable(TableName.valueOf(tableName)); System.out.println("表已洗掉"); } // 增、改 public static void putData(String tableName, String rowKey, String cf, String cn, String value) throws IOException { // 獲取表物件// HTable table=new HTable(conf,TableName.valueOf(tableName)); 已過時 Table table = connection.getTable(TableName.valueOf(tableName)); // 創建put物件 Put put = new Put(Bytes.toBytes(rowKey)); // 添加資料 put.addColumn(Bytes.toBytes(cf), Bytes.toBytes(cn), Bytes.toBytes(value)); // 執行添加操作 table.put(put); } // 刪 public static void delete(String tableName, String rowKey, String cf, String cn) throws IOException { // 獲取table物件 Table table = connection.getTable(TableName.valueOf(tableName)); // 創建delete物件 Delete delete = new Delete(Bytes.toBytes(rowKey));// 洗掉整個列族 delete.addColumns(Bytes.toBytes(cf), Bytes.toBytes(cn));// 洗掉所有版本// delete.addColumn(Bytes.toBytes(cf), Bytes.toBytes(cn));不推薦，只洗掉最新的版本 // 執行洗掉操作 table.delete(delete); table.close(); } // 查——全表掃描，只能獲取最新版本 public static void scanTable(String tableName) throws IOException { // 獲取table物件 Table table = connection.getTable(TableName.valueOf(tableName)); // 構建掃描器 Scan scan = new Scan(); ResultScanner resultScanner = table.getScanner(scan); // 遍歷資料并列印 for (Result result : resultScanner) { // rowkey Cell[] cells = result.rawCells(); for (Cell cell : cells) { // cell System.out.println("RK:" + Bytes.toString(CellUtil.cloneRow(cell)) + ",CF:" + Bytes.toString(CellUtil.cloneFamily(cell)) + ",CN:" + Bytes.toString(CellUtil.cloneQualifier(cell)) + ",VALUE:" + Bytes.toString(CellUtil.cloneValue(cell))); } } table.close(); } // 查——獲取指定列族 public static void getData(String tableName, String rowKey, String cf, String cn) throws IOException { Table table = connection.getTable(TableName.valueOf(tableName)); Get get = new Get(Bytes.toBytes(rowKey)); get.addColumn(Bytes.toBytes(cf), Bytes.toBytes(cn));// get.addFamily(cf);// get.setMaxVersions();//不傳參默認是表結構內的maxversions get.setMaxVersions(2); Result result = table.get(get); Cell[] cells = result.rawCells(); for (Cell cell : cells) { // cell System.out.println("RK:" + Bytes.toString(CellUtil.cloneRow(cell)) + ",CF:" + Bytes.toString(CellUtil.cloneFamily(cell)) + ",CN:" + Bytes.toString(CellUtil.cloneQualifier(cell)) + ",VALUE:" + Bytes.toString(CellUtil.cloneValue(cell))); } } public static void main(String[] args) throws IOException { // 判斷表是否存在// System.out.println(tableExist("student"));// System.out.println(tableExist("staff")); // 創建表// createTable("staff", "info");// System.out.println(tableExist("staff")); // 洗掉表// deleteTable("staff"); // 增、改// putData("student", "1001", "info", "name", "mcq"); // 刪// delete("student", "1001", "info", "name"); // 查——全表掃描// scanTable("student"); //查——獲取指定列族 getData("student", "1001","info","name"); // 關閉資源 close(connection, admin); }}
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標籤：大數據