须知
Hbase数据最终是在hdfs上的，具体来说应该是在hdfs上一个叫做/hbase的目录下。具体结构如下：
所以java访问Hbase其实就是访问hdfs，所以环境搭建跟hadoop开发环境使用没什么不同。
实战部分
1.导入需要的jar包，此处在java项目引入Hbase解压后lib目录下所有jar包即可。里面提供了访问Hbase的api接口，也有与hadoop集成的客户端jar包。
2.将hbase-site.xml拷贝到classpath根目录下，这样，hbase在创建configuration对象会自动加载，hbase源码此部分：
public static Configuration addHbaseResources(Configuration conf){conf.addResource("hbase-default.xml");conf.addResource("hbase-site.xml");checkDefaultsVersion(conf);checkForClusterFreeMemoryLimit(conf);return conf;}
具体文件hbase-site.xml参照内容如下：
<configuration>
<property><name>hbase.rootdir</name><value>hdfs://chidianwei-VirtualBox:9000/hbase</value></property><property><name>hbase.cluster.distributed</name><value>true</value></property><property><name>hbase.zookeeper.quorum</name><value>chidianwei-VirtualBox</value></property><property><name>dfs.replication</name><value>1</value></property>
</configuration>3.下面我们就可以写一个初始化表测试类，创建了两张表，word和stat。（其中的HbaseUtil类代码见最后一步）代码如下：
public class InitData {public static void main(String[] args) throws IOException {//创建一个word表，只有一个列族contentHBaseUtil.createTable("word","content");//获取word表HTable htable = HBaseUtil.getHTable("word");htable.setAutoFlush(false);//创建测试数据List<Put> puts = new ArrayList<Put>();Put put1 = HBaseUtil.getPut("1","content",null,"The Apache Hadoop software library is a framework");Put put2 = HBaseUtil.getPut("2","content",null,"The common utilities that support the other Hadoop modules");Put put3 = HBaseUtil.getPut("3","content",null,"Hadoop by reading the documentation");Put put4 = HBaseUtil.getPut("4","content",null,"Hadoop from the release page");Put put5 = HBaseUtil.getPut("5","content",null,"Hadoop on the mailing list");puts.add(put1);puts.add(put2);puts.add(put3);puts.add(put4);puts.add(put5);//提交测试数据htable.put(puts);htable.flushCommits();htable.close();//创建stat表，只有一个列祖resultHBaseUtil.createTable("stat","result");}
}4.hbase工具类，里面涉及到java对hbase数据库创建表，删除表，常见的crud操作等等。具体参照代码：
package com.oracle.hbase.weifenbushi;import java.io.IOException;
import java.util.Arrays;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.MasterNotRunningException;
import org.apache.hadoop.hbase.ZooKeeperConnectionException;
import org.apache.hadoop.hbase.client.Get;
import org.apache.hadoop.hbase.client.HBaseAdmin;
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.filter.CompareFilter.CompareOp;
import org.apache.hadoop.hbase.filter.Filter;
import org.apache.hadoop.hbase.filter.FilterList;
import org.apache.hadoop.hbase.filter.FilterList.Operator;
import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
import org.apache.hadoop.hbase.util.Bytes;public class HBaseUtil {/*** 初始化HBase的配置文件* @return*/public static Configuration getConfiguration(){Configuration conf = HBaseConfiguration.create();//和hbase-site.xml中配置的一致conf.set("hbase.zooker.quorum", "192.168.10.127");
// conf.set("hbase.zooker.quorum", "oraclehadoop1");return conf;}/*** 实例化HBaseAdmin,HBaseAdmin用于对表的元素据进行操作* @return* @throws MasterNotRunningException* @throws ZooKeeperConnectionException*/public static HBaseAdmin getHBaseAdmin() throws MasterNotRunningException, ZooKeeperConnectionException{HBaseAdmin a=null;try {a= new HBaseAdmin(getConfiguration());} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}return a;}/*** 创建表* @param tableName 表名* @param columnFamilies 列族* @throws IOException*/public static void createTable(String tableName,String...columnFamilies) throws IOException {HTableDescriptor htd = new HTableDescriptor(tableName.getBytes());//for(String fc : columnFamilies) {htd.addFamily(new HColumnDescriptor(fc));}getHBaseAdmin().createTable(htd);}/*** 获取HTableDescriptor* @param tableName* @return* @throws IOException*/public static HTableDescriptor getHTableDescriptor(byte[] tableName) throws IOException{return getHBaseAdmin().getTableDescriptor(tableName); }/*** 获取表* @param tableName 表名* @return* @throws IOException*/public static HTable getHTable(String tableName) throws IOException{return new HTable(getConfiguration(),tableName);}/*** 获取Put,Put是插入一行数据的封装格式* @param tableName* @param row* @param columnFamily* @param qualifier* @param value* @return* @throws IOException*/public static Put getPut(String row,String columnFamily,String qualifier,String value) throws IOException{Put put = new Put(row.getBytes());if(qualifier==null||"".equals(qualifier)) {put.add(columnFamily.getBytes(), null, value.getBytes());}else {put.add(columnFamily.getBytes(), qualifier.getBytes(), value.getBytes());}return put;}/*** 查询某一行的数据* @param tableName 表名* @param row 行键* @return* @throws IOException*/public static Result getResult(String tableName,String row) throws IOException {Get get = new Get(row.getBytes());HTable htable = getHTable(tableName);Result result = htable.get(get);htable.close();return result;}/*** 条件查询* @param tableName 表名* @param columnFamily 列族* @param queryCondition 查询条件值* @param begin 查询的起始行* @param end 查询的终止行* @return* @throws IOException*/public static ResultScanner getResultScanner(String tableName,String columnFamily,String queryCondition,String begin,String end) throws IOException{Scan scan = new Scan();//设置起始行scan.setStartRow(Bytes.toBytes(begin));//设置终止行scan.setStopRow(Bytes.toBytes(end));//指定要查询的列族scan.addColumn(Bytes.toBytes(columnFamily),null);//查询列族中值等于queryCondition的记录Filter filter1 = new SingleColumnValueFilter(Bytes.toBytes(columnFamily),null,CompareOp.EQUAL,Bytes.toBytes(queryCondition));//Filter filter2 = new SingleColumnValueFilter(Bytes.toBytes(columnFamily),null,CompareOp.EQUAL,Bytes.toBytes("chuliuxiang"));FilterList filterList = new FilterList(Operator.MUST_PASS_ONE,Arrays.asList(filter1));scan.setFilter(filterList);HTable htable = getHTable(tableName);ResultScanner rs = htable.getScanner(scan);htable.close();return rs;}public static void main(String[] args) {try {Result result = getResult("word", "1");System.out.println(new String(result.list().get(0).getValue()));} catch (IOException e) {// TODO Auto-generated catch blocke.printStackTrace();}}}
总结：
以上就是java对hbase伪分布式的访问，对集群的访问也是一样，api是不会变的，变化的是配置文件，对应的quorum是zookeeper集群，配置变为： conf.set("hbase.zookeeper.quorum", "weekend05:2181,weekend06:2181,weekend07:2181");
ok，希望对大家会有帮助。
