HBase-1.0.1学习笔记（五）HBase Java客户
发表于：2025-02-03 作者：千家信息网编辑
千家信息网最后更新 2025年02月03日，鲁春利的工作笔记，好记性不如烂笔头Java客户端:org.apache.hadoop.hbase.client.HTable类：该类的读写是非线程安全的，不再作为client API提供给开发用户使用
千家信息网最后更新 2025年02月03日HBase-1.0.1学习笔记（五）HBase Java客户
:。 * static TableName valueOf(byte[] fullName) * static TableName valueOf(byte[] namespace, byte[] qualifier) * static TableName valueOf(ByteBuffer namespace, ByteBuffer qualifier) * static TableName valueOf(String name) * static TableName valueOf(String namespaceAsString, String qualifierAsString) * HBase系统默认定义了两个缺省的namespace * hbase：系统内建表，包括namespace和meta表 * default：用户建表时未指定namespace的表都创建在此 * 在HBase中，namespace命名空间指对一组表的逻辑分组，类似RDBMS中的database，方便对表在业务上划分。 * */ TableName tableName = TableName.valueOf(TABLE_NAME); boolean exists = admin.tableExists(tableName); if (exists) { LOG.info("Table " + tableName.getNameAsString() + " already exists."); } else { LOG.info("Table " + tableName.getNameAsString() + " not exists."); } return exists; } /** * 创建表 * @param admin * @throws IOException */ private void createTable (Admin admin) throws IOException { TableName tableName = TableName.valueOf(TABLE_NAME); LOG.info("To create table named " + TABLE_NAME); HTableDescriptor tableDesc = new HTableDescriptor(tableName); HColumnDescriptor columnDesc = new HColumnDescriptor(COLUMN_FAMILY_NAME); tableDesc.addFamily(columnDesc); admin.createTable(tableDesc); } /** * 删除表 * @param admin * @throws IOException */ private void deleteTable (Admin admin) throws IOException { TableName tableName = TableName.valueOf(TABLE_NAME); LOG.info("disable and then delete table named " + TABLE_NAME); admin.disableTable(tableName); admin.deleteTable(tableName); } /** * 添加数据 * @param connection * @throws IOException */ private void putDatas (Connection connection) throws IOException { String [] rows = {"baidu.com_19991011_20151011", "alibaba.com_19990415_20220523"}; String [] columns = {"owner", "ipstr", "access_server", "reg_date", "exp_date"}; String [][] values = { {"Beijing Baidu Technology Co.", "220.181.57.217", "北京", "1999年10月11日", "2015年10月11日"}, {"Hangzhou Alibaba Advertising Co.", "205.204.101.42", "杭州", "1999年04月15日", "2022年05月23日"} }; TableName tableName = TableName.valueOf(TABLE_NAME); byte [] family = Bytes.toBytes(COLUMN_FAMILY_NAME); Table table = connection.getTable(tableName); for (int i = 0; i < rows.length; i++) { System.out.println("========================" + rows[i]); byte [] rowkey = Bytes.toBytes(rows[i]); Put put = new Put(rowkey); for (int j = 0; j < columns.length; j++) { byte [] qualifier = Bytes.toBytes(columns[j]); byte [] value = Bytes.toBytes(values[i][j]); put.addColumn(family, qualifier, value); } table.put(put); } table.close(); } /** * 检索数据-单行获取 * @param connection * @throws IOException */ private void getData(Connection connection) throws IOException { LOG.info("Get data from table " + TABLE_NAME + " by family."); TableName tableName = TableName.valueOf(TABLE_NAME); byte [] family = Bytes.toBytes(COLUMN_FAMILY_NAME); byte [] row = Bytes.toBytes("baidu.com_19991011_20151011"); Table table = connection.getTable(tableName); Get get = new Get(row); get.addFamily(family); // 也可以通过addFamily或addColumn来限定查询的数据 Result result = table.get(get); List
鲁春利的工作笔记，好记性不如烂笔头
Java客户端:
org.apache.hadoop.hbase.client.HTable类：该类的读写是非线程安全的，不再作为client API提供给开发用户使用，建议通过Table类替代。
/** * Creates an object to access a HBase table. * @param conf Configuration object to use. * @param tableName Name of the table. * @throws IOException if a remote or network exception occurs * @deprecated Constructing HTable objects manually has been deprecated. * {@link Connection} to instantiate a {@link Table} instead. */ @Deprecated public HTable(Configuration conf, final String tableName) throws IOException { this(conf, TableName.valueOf(tableName)); }org.apache.hadoop.hbase.client.Table类：
org.apache.hadoop.hbase.client.HConnectionManager类：
org.apache.hadoop.hbase.client.HBaseAdmin类：
@InterfaceAudience.Private@InterfaceStability.Evolvingpublic class HBaseAdmin implements Admin { private static final Log LOG = LogFactory.getLog(HBaseAdmin.class); // 略 @Deprecated public HBaseAdmin(Configuration c) throws MasterNotRunningException, ZooKeeperConnectionException, IOException { // Will not leak connections, as the new implementation of the constructor // does not throw exceptions anymore. this(ConnectionManager.getConnectionInternal(new Configuration(c))); this.cleanupConnectionOnClose = true; } // 略｝# 说明：HBaseAdmin不在作为客户端API使用，标记为Private表示为HBase-internal class。# 使用Connection#getAdmin()来获取Admin实例。org.apache.hadoop.hbase.client.ConnectionFactory类：
@InterfaceAudience.Public@InterfaceStability.Evolvingpublic class ConnectionFactoryextends Object// Example: Connection connection = ConnectionFactory.createConnection(config); Table table = connection.getTable(TableName.valueOf("table1")); try { // Use the table as needed, for a single operation and a single thread } finally { table.close(); connection.close(); }客户端使用示例：
package com.invic.hbase;import java.io.IOException;import java.util.Iterator;import java.util.List;import org.apache.commons.logging.Log;import org.apache.commons.logging.LogFactory;import org.apache.hadoop.conf.Configuration;import org.apache.hadoop.hbase.Cell;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.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.filter.Filter;import org.apache.hadoop.hbase.filter.PageFilter;import org.apache.hadoop.hbase.util.Bytes;/** * * @author lucl * HBase的配置实例 * */public class HBaseManagerMain { private static final Log LOG = LogFactory.getLog(HBaseManagerMain.class); // 在Eclipse中运行时报错如下 // Caused by: java.lang.ClassNotFoundException: org.apache.htrace.Trace // Caused by: java.lang.NoClassDefFoundError: io/netty/channel/ChannelHandler // 需要把单独的htrace-core-3.1.0-incubating.jar和netty-all-4.0.5.final.jar导入项目中 private static final String TABLE_NAME = "m_domain"; private static final String COLUMN_FAMILY_NAME = "cf"; /** * @param args */ public static void main(String[] args) { Configuration conf = HBaseConfiguration.create(); conf.set("hbase.master", "nnode:60000"); conf.set("hbase.zookeeper.property.clientport", "2181"); conf.set("hbase.zookeeper.quorum", "nnode,dnode1,dnode2"); HBaseManagerMain manageMain = new HBaseManagerMain(); try { /** * HTable类读写时是非线程安全的，已经标记为Deprecated * 建议通过org.apache.hadoop.hbase.client.Connection来获取实例 */ Connection connection = ConnectionFactory.createConnection(conf); Admin admin = connection.getAdmin(); /** * 列出所有的表 */ manageMain.listTables(admin); /** * 判断表m_domain是否存在 */ boolean exists = manageMain.isExists(admin); /** * 存在就删除 */ if (exists) { manageMain.deleteTable(admin); } /** * 创建表 */ manageMain.createTable(admin); /** * 再次列出所有的表 */ manageMain.listTables(admin); /** * 添加数据 */ manageMain.putDatas(connection); /** * 检索数据-表扫描 */ manageMain.scanTable(connection); /** * 检索数据-单行读 */ manageMain.getData(connection); /** * 检索数据-根据条件 */ manageMain.queryByFilter(connection); /** * 删除数据 */ manageMain.deleteDatas(connection); } catch (IOException e) { e.printStackTrace(); } } /** * 列出表 * @param admin * @throws IOException */ private void listTables (Admin admin) throws IOException { TableName [] names = admin.listTableNames(); for (TableName tableName : names) { LOG.info("Table Name is : " + tableName.getNameAsString()); } } /** * 判断表是否存在 * @param admin * @return * @throws IOException */ private boolean isExists (Admin admin) throws IOException { /** * org.apache.hadoop.hbase.TableName为为代表了表名字的Immutable POJO class对象, * 形式为
