作业4-8-7：HBase的Java 编程（增删改查）

素颜马尾好姑娘i 2022-11-17 03:49 28阅读 0赞

### 1、请使用Java API实现以下功能，并将程序代码和运行结果都截图提交。 ###

1.  列出所有表名
2.  创建表
3.  删除表
4.  插入一条数据到单元格
5.  删除一个单元格的数据
6.  显示打印一个单元格的数据信息

正确答案：

我的答案：

package com.test;
    import java.io.IOException;
    import org.apache.hadoop.conf.*;
    import org.apache.hadoop.hbase.*;
    import org.apache.hadoop.hbase.client.*;
    public class HBaseTset {
    
     public static void main(String[] args) {
    
     list()；
    
     //createTable("tb3",new String[] {"lie1","lie2","lie3","lie4"});
     //deleteTable("sc");
     //insertData("course","c01","Cname","","Lucy");
     //insertData("course","c01","Ccredit","Math","85");
     //deleteData("course","c02","Cname","");
    
     printData("course","c01","Ccredit","Math");
     printData("course","c01","Cname","");
    
     list();
    
     }
    
     //1.Configuration：配置类
    
     private static Configuration conf;
    
     //2.Connection：连接类
    
     private static Connection conn;
    
     //3.Admin:管理员类
    
     private static Admin admin;
    
     
     //显示打印一个单元格的数据信息
    
     public static void printData(String tableName,String rowKey,String colFamily,String col) {
    
     init();
    
     try {
    
     Table t = conn.getTable(TableName.valueOf(tableName));
    
     Get get = new Get(rowKey.getBytes());
    
     get.addFamily(colFamily.getBytes());
    
     get.addColumn(colFamily.getBytes(), col.getBytes());
    
     Result result = t.get(get);
    
     printResult(result);
    
     t.close(); 
    
     } catch (IOException e) {
    
     e.printStackTrace();
    
     }close();
    
     }
    
     private static void printResult(Result result) {
    
     // TODO Auto-generated method stub
    
     
    
     }
    
     //删除一个单元格的数据
    
     public static void deleteData(String tableName,String rowKey,String colFamily,String col) {
    
     init();
    
     try {
    
     Table t = conn.getTable(TableName.valueOf(tableName));
    
     Delete delete = new Delete(rowKey.getBytes());
    
     delete.addFamily(colFamily.getBytes());
    
     delete.addColumn(colFamily.getBytes(), col.getBytes());
    
     t.delete(delete);
    
     t.close();
    
     System.out.println("数据删除成功！");
    
     } catch (IOException e) {
    
     e.printStackTrace();
    
     }close();
    
     }
    
     //插入一条数据到单元格
    
     public static void insertData(String tableName,String rowKey,String colFamily,String col,String val) {
    
     init();
    
     TableName tn = TableName.valueOf(tableName);
    
     try {
    
     Table t = conn.getTable(tn);
    
     Put put = new Put(rowKey.getBytes());
    
     put.addColumn(colFamily.getBytes(), col.getBytes(), val.getBytes());
    
     t.put(put);
    
     t.close();
    
     System.out.println("添加数据成功！"); 
    
     } catch (IOException e) {
    
     e.printStackTrace();
    
     }close();
    
     }
    
     
    
     //删除表
    
     public static void deleteTable(String tableName) {
    
     init();
    
     //1.String型tableName封装成TableName
    
     TableName tn = TableName.valueOf(tableName);
    
     //2.判断表是否存在
    
     try {
    
     if(admin.tableExists(tn)) {
    
     //1.disable
    
     admin.disableTable(tn);
    
     //2.删除表
    
     admin.deleteTable(tn);
    
     System.out.println(tableName+"删除成功！");
    
     }
    
      }catch (IOException e) {
    
     e.printStackTrace();
    
     }close();
    
     }
    
     //创建表
    
      public static void createTable(String tableName,String[] colFamilies) {
    
       init();
    
       TableName tn = TableName.valueOf(tableName);
    
       try {
    
        if(admin.tableExists(tn)) {
    
         System.out.println(tableName+"已经存在，不能创建！");
    
        }else {
    
         HTableDescriptor htd = new HTableDescriptor(tn);
    
         for(String colFamily:colFamilies) {
    
          HColumnDescriptor hcd = new HColumnDescriptor(colFamily);
    
          htd.addFamily(hcd);
    
         }
    
         admin.createTable(htd);
    
         System.out.println(tableName+"创建成功！");
    
        }
    
       } catch (IOException e) {
    
        e.printStackTrace();
    
       }
    
       close();
    
      }
    
     //list方法
    
     public static void list() {
    
     init(); //初始化
    
     try {
    
     TableName[] tns = admin.listTableNames();
    
     //遍历数组
    
     for(TableName tn:tns) {
    
     System.out.println(tn.toString());
    
     }
    
     } catch (IOException e) {
    
     e.printStackTrace();
    
     }
    
     close();
    
     }
    
     //1.初始化的方法
    
     public static void init() {
    
     conf = HBaseConfiguration.create();
    
     //做配置
    
     conf.set("hbase.rootdir", "hdfs://localhost:9000/hbase");
    
     //得到连接
    
     try {
    
     conn = ConnectionFactory.createConnection(conf);
    
     //得到管理员admin
    
     admin = conn.getAdmin();
    
     } catch (IOException e) {
    
     // TODO Auto-generated catch block
    
     e.printStackTrace();
    
     }
    
     }
    
     //2.关闭的方法
    
     public static void close() {
    
     if(admin !=null){
    
     try {
    
     admin.close();
    
     } catch (IOException e) {
    
     // TODO Auto-generated catch block
    
     e.printStackTrace();
    
     }
    
     }
    
     if(conn!=null) {
    
     try {
    
     conn.close();
    
     } catch (IOException e) {
    
     // TODO Auto-generated catch block
    
     e.printStackTrace();
    
     }
    
     }
    
     }
    
    }

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[97303336e20bcb774be61b83a5d57165.png]: /images/20221022/bb43869b1d474527a89cd066dd2da626.png