educoder-HBase 开发：使用Java操作HBase各关卡通关答案

约定不等于承诺〃 2022-10-06 01:58 170阅读 0赞

## 第1关：创建表 ##

package step1;
    import java.io.IOException;
    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.TableName;
    import org.apache.hadoop.hbase.client.Admin;
    import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
    import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
    import org.apache.hadoop.hbase.client.Connection;
    import org.apache.hadoop.hbase.client.ConnectionFactory;
    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.client.TableDescriptor;
    import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
    import org.apache.hadoop.hbase.util.Bytes;
    /**
    * HBase 1.0 version of ExampleClient that uses {@code Connection},
    * {@code Admin} and {@code Table}.
    */
    public class Task{
        
    public void createTable()throws Exception{
        
    /********* Begin *********/
    Configuration config = HBaseConfiguration.create();
    Connection connection = ConnectionFactory.createConnection(config);
    try {
        
    // Create table
    Admin admin = connection.getAdmin();
    try {
        
    TableName tableName = TableName.valueOf("dept");
    // 新 API 构建表
    // TableDescriptor 对象通过 TableDescriptorBuilder 构建；
    TableDescriptorBuilder tableDescriptor =
    TableDescriptorBuilder.newBuilder(tableName);
    ColumnFamilyDescriptor family =
    ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes("data")).build();// 构建列族对象
    tableDescriptor.setColumnFamily(family); // 设置列族
    admin.createTable(tableDescriptor.build()); // 创建表
    
    
    TableName emp = TableName.valueOf("emp");
    // 新 API 构建表
    // TableDescriptor 对象通过 TableDescriptorBuilder 构建；
    TableDescriptorBuilder empDescriptor =
    TableDescriptorBuilder.newBuilder(emp);
    ColumnFamilyDescriptor empfamily =
    ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes("emp")).build();// 构建列族对象
    empDescriptor.setColumnFamily(empfamily); // 设置列族
    admin.createTable(empDescriptor.build()); // 创建表
    } finally {
        
    admin.close();
    }
    } finally {
        
    connection.close();
    }
    /********* End *********/
    }
    }

命令行：
    
    start-dfs.sh （ Hadoop 启动）
    回车
    start-hbase.sh （ hbase 启动）

## 第2关：添加数据 ##

package step2;
    import java.io.IOException;
    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.TableName;
    import org.apache.hadoop.hbase.client.Admin;
    import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
    import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
    import org.apache.hadoop.hbase.client.Connection;
    import org.apache.hadoop.hbase.client.ConnectionFactory;
    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.client.TableDescriptor;
    import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
    import org.apache.hadoop.hbase.util.Bytes;
    public class Task {
        
     public void insertInfo()throws Exception{
        
     /********* Begin *********/
     Configuration config = HBaseConfiguration.create();
     Connection connection = ConnectionFactory.createConnection(config);
     Admin admin = connection.getAdmin();
     TableName tableName = TableName.valueOf("tb_step2");
     TableDescriptorBuilder tableDescriptor = TableDescriptorBuilder.newBuilder(tableName);
     ColumnFamilyDescriptor family = ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes("data")).build();//  构建列族对象
     tableDescriptor.setColumnFamily(family); //  设置列族
     admin.createTable(tableDescriptor.build()); //  创建表
     // 添加数据
     byte[] row1 = Bytes.toBytes("row1");
     Put put1 = new Put(row1); 
     byte[] columnFamily1 = Bytes.toBytes("data"); // 列
     byte[] qualifier1 = Bytes.toBytes(String.valueOf(1)); // 列族修饰词
     byte[] value1 = Bytes.toBytes("张三丰"); // 值
     put1.addColumn(columnFamily1, qualifier1, value1);
     byte[] row2 = Bytes.toBytes("row2");
     Put put2 = new Put(row2); 
     byte[] columnFamily2 = Bytes.toBytes("data"); // 列
     byte[] qualifier2 = Bytes.toBytes(String.valueOf(2)); // 列族修饰词
     byte[] value2 = Bytes.toBytes("张无忌"); // 值
     put2.addColumn(columnFamily2, qualifier2, value2);
     Table table = connection.getTable(tableName);
     table.put(put1);
     table.put(put2);
     /********* End *********/
     }
    }

## 第3关：获取数据 ##

package step3;
    import java.io.IOException;
    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.TableName;
    import org.apache.hadoop.hbase.client.Admin;
    import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
    import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
    import org.apache.hadoop.hbase.client.Connection;
    import org.apache.hadoop.hbase.client.ConnectionFactory;
    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.client.TableDescriptor;
    import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
    import org.apache.hadoop.hbase.util.Bytes;
    public class Task {
        
     public void queryTableInfo()throws Exception{
        
     /********* Begin *********/
     Configuration config = HBaseConfiguration.create();
     Connection connection = ConnectionFactory.createConnection(config);
     Admin admin = connection.getAdmin();
     TableName tableName = TableName.valueOf("t_step3");
     Table table = connection.getTable(tableName);
     // 获取数据
     Get get = new Get(Bytes.toBytes("row1")); // 定义 get 对象
     Result result = table.get(get); // 通过 table 对象获取数据
     //System.out.println("Result: " + result);
     // 很多时候我们只需要获取“值”   这里表示获取  data:1  列族的值
     byte[] valueBytes = result.getValue(Bytes.toBytes("data"), Bytes.toBytes("1")); // 获取到的是字节数组
     // 将字节转成字符串
     String valueStr = new String(valueBytes,"utf-8");
     System.out.println("value:" + valueStr);
     TableName tableStep3Name = TableName.valueOf("table_step3");
     Table step3Table = connection.getTable(tableStep3Name);
     // 批量查询
     Scan scan = new Scan();
     ResultScanner scanner = step3Table.getScanner(scan);
     try {
        
     int i = 0;
     for (Result scannerResult: scanner) {
        
     //byte[] value = scannerResult.getValue(Bytes.toBytes("data"), Bytes.toBytes(1));
     // System.out.println("Scan: " + scannerResult);
     byte[] row = scannerResult.getRow();
     System.out.println("rowName:" + new String(row,"utf-8"));
     }
     } finally {
        
     scanner.close();
     }
     /********* End *********/
     }
    }

## 第4关：删除表 ##

package step4;
    import java.io.IOException;
    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.TableName;
    import org.apache.hadoop.hbase.client.Admin;
    import org.apache.hadoop.hbase.client.ColumnFamilyDescriptor;
    import org.apache.hadoop.hbase.client.ColumnFamilyDescriptorBuilder;
    import org.apache.hadoop.hbase.client.Connection;
    import org.apache.hadoop.hbase.client.ConnectionFactory;
    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.client.TableDescriptor;
    import org.apache.hadoop.hbase.client.TableDescriptorBuilder;
    import org.apache.hadoop.hbase.util.Bytes;
    public class Task {
        
     public void deleteTable()throws Exception{
        
     /********* Begin *********/
     Configuration config = HBaseConfiguration.create();
     Connection connection = ConnectionFactory.createConnection(config);
     Admin admin = connection.getAdmin();
     TableName tableName = TableName.valueOf("t_step4");
     admin.disableTable(tableName);
     admin.deleteTable(tableName);
     /********* End *********/
     }
    }