Windows平台下的Java远程操作Linux系统中的HBase

迷南。 2022-06-09 08:47 124阅读 0赞

首先修改过windows客户端的C:\\Windows\\System32\\drivers\\etc\\hosts文件，添加hadoop集群的节点IP地址：

192.168.180.137 master
    192.168.180.135 slave-1
    192.168.180.134 slave-2

我这是用的maven管理jar包，现在pom.xml加入Hbase的jar包依赖：

<dependency>
        <groupId>org.apache.hbase</groupId>
        <artifactId>hbase</artifactId>
        <version>1.3.1</version>
        <type>pom</type>
    </dependency>

启动hadoop集群以及Hbase，这里就不多说了，直接进入代码阶段：

连接Linux系统上Hbase数据库，这里的192.168.180.137:2181要与Linux上Hbase的hbase-site.xml一致，以确保能连接上HBase数据库：

Configuration HBASE_CONFIG = new Configuration();  
      
     HBASE_CONFIG.set("hbase.zookeeper.quorum", "192.168.180.137:2181");  
      
     cfg = new HBaseConfiguration(HBASE_CONFIG);  
            
     admin = new HBaseAdmin(cfg);

首先先试试创建一张student表：

// 创建一张表，指定表名，列族  
        public void createTable(String tableName, String columnFarily)  
                throws Exception {  
      
            if (admin.tableExists(tableName)) {  
                System.out.println(tableName + "存在！");  
                System.exit(0);  
            } else {  
                HTableDescriptor tableDesc = new HTableDescriptor(tableName);  
                tableDesc.addFamily(new HColumnDescriptor(columnFarily));  
                admin.createTable(tableDesc);  
                System.out.println("创建表成功！");  
            }  
        }

测试：

public static void main(String[] args) {  
            try {  
                HbaseTest hbase = new HbaseTest();  
                hbase.createTable("student", "fam1");  
                //hbase.getAllTables();  
      
            }catch (Exception e) {  
                e.printStackTrace();  
            }  
        }

![这里写图片描述][SouthEast]

这里我们可以看到，在hadoop的Hbase数据库中有了一张student表。

这是一个插入数据的例子，插入数据，主要用到的是Hbase的Put方法：

package Hbase.HbaseTest;
    
    import java.io.IOException;
    
    import org.apache.hadoop.conf.Configuration;
    import org.apache.hadoop.hbase.HBaseConfiguration;
    import org.apache.hadoop.hbase.client.HTable;
    import org.apache.hadoop.hbase.client.Put;
    import org.apache.hadoop.hbase.util.Bytes;
    
    public class InsertData {
    	public static void main(String[] args) throws IOException {
    
    		// Instantiating Configuration class
    		//Configuration config = HBaseConfiguration.create();
    		Configuration HBASE_CONFIG = new Configuration();  
    		  
            HBASE_CONFIG.set("hbase.zookeeper.quorum", "192.168.180.137:2181");  
            HBaseConfiguration config = new HBaseConfiguration(HBASE_CONFIG);
    
    		// Instantiating HTable class
    		HTable hTable = new HTable(config, "emp");
    
    		// Instantiating Put class
    		// accepts a row name.
    		Put p = new Put(Bytes.toBytes("row1"));
    
    		// adding values using add() method
    		// accepts column family name, qualifier/row name ,value
    		p.add(Bytes.toBytes("personal data"), Bytes.toBytes("name"), Bytes.toBytes("raju"));
    
    		p.add(Bytes.toBytes("personal data"), Bytes.toBytes("city"), Bytes.toBytes("hyderabad"));
    
    		p.add(Bytes.toBytes("professional data"), Bytes.toBytes("designation"), Bytes.toBytes("manager"));
    
    		p.add(Bytes.toBytes("professional data"), Bytes.toBytes("salary"), Bytes.toBytes("50000"));
    
    		// Saving the put Instance to the HTable.
    		hTable.put(p);
    		System.out.println("data inserted");
    
    		// closing HTable
    		hTable.close();
    
    	}
    
    }

![这里写图片描述][SouthEast 1]

接下来是查询例子，主要用到的是get()方法，这里查询的是personal data的name和city的值：

package Hbase.HbaseTest;
    
    import java.io.IOException;
    
    import org.apache.hadoop.conf.Configuration;
    import org.apache.hadoop.hbase.HBaseConfiguration;
    import org.apache.hadoop.hbase.client.Get;
    import org.apache.hadoop.hbase.client.HTable;
    import org.apache.hadoop.hbase.client.Result;
    import org.apache.hadoop.hbase.util.Bytes;
    
    public class RetriveData {
    	public static void main(String[] args) throws IOException {
    		Configuration HBASE_CONFIG = new Configuration();
    
    		HBASE_CONFIG.set("hbase.zookeeper.quorum", "192.168.180.137:2181");
    		HBaseConfiguration config = new HBaseConfiguration(HBASE_CONFIG);
    
    		// Instantiating HTable class
    		HTable table = new HTable(config, "emp");
    
    		Get g = new Get(Bytes.toBytes("row1"));
    
    		// Reading the data
    		Result result = table.get(g);
    
    		// Reading values from Result class object
    		byte[] value = result.getValue(Bytes.toBytes("personal data"), Bytes.toBytes("name"));
    
    		byte[] value1 = result.getValue(Bytes.toBytes("personal data"), Bytes.toBytes("city"));
    
    		// Printing the values
    		String name = Bytes.toString(value);
    		String city = Bytes.toString(value1);
    
    		System.out.println("name: " + name + " city: " + city);
    	}
    
    }

![这里写图片描述][SouthEast 2]

控制台输出的信息与shell命名查询对比，我们可以看到查询到的信息与HBase数据库里的信息一致。  
![这里写图片描述][SouthEast 3]

以上的例子参考于：[http://www.yiibai.com/hbase/hbase\_read\_data.html\#article-start和http://blog.csdn.net/kkdelta/article/details/20457319][http_www.yiibai.com_hbase_hbase_read_data.html_article-start_http_blog.csdn.net_kkdelta_article_details_20457319]

[SouthEast]: /images/20220609/2b1bdfd3e70a4a57a15f7ddf21f7b3d5.png
[SouthEast 1]: /images/20220609/d0ea304070c14f1fbdffc27000e20245.png
[SouthEast 2]: /images/20220609/439246a25caf4539bcbac00a6945fd09.png
[SouthEast 3]: /images/20220609/fbd7cdc98ac24d868bdeff874c19a6db.png
[http_www.yiibai.com_hbase_hbase_read_data.html_article-start_http_blog.csdn.net_kkdelta_article_details_20457319]: http://www.yiibai.com/hbase/hbase_read_data.html#article-start%E5%92%8Chttp://blog.csdn.net/kkdelta/article/details/20457319