大三每日总结

今日完成,修改hbasebug,不过出现新的bug,但不影响hbase的正常使用.

顺利实现idea连接hbase数据库,同时顺利实现hbase数据库中数据的增删改查,以下是相关代码

package org.example;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.client.AsyncConnection;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;

import java.io.IOException;
import java.util.concurrent.CompletableFuture;

public class HbaseConection {
    //声明静态属性
    public static Connection connection = null;
    static {
        try {
            connection = ConnectionFactory.createConnection();
        } catch (IOException e) {
            System.out.println("连接获取失败");
            throw new RuntimeException(e);
        }
    }
    public static void closeConnection() throws IOException {
        if(connection != null)
        connection.close();
    }
    public static void main(String[] args) throws IOException {
        System.out.println(HbaseConection.connection);
        HbaseConection.closeConnection();
    }
}

package org.example;

import org.apache.hadoop.hbase.NamespaceDescriptor;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.util.Bytes;

import java.io.IOException;

public class HBaseDDL {
    // 添加静态属性 connection 指向单例连接
    public static Connection connection = HbaseConection.connection;
    //创建表格
    public static void createNamespace(String namespace) throws IOException {
        Admin admin = connection.getAdmin();
        NamespaceDescriptor.Builder builder = NamespaceDescriptor.create(namespace);
        builder.addConfiguration("user","atguigu");
        try {
            admin.createNamespace(builder.build());
        } catch (IOException e) {
            System.out.println("命令空间已经存在");
            e.printStackTrace();
        }
        admin.close();
    }
    //判断命名空间是否存在namespace命名空间,tablename表格名
    public static  boolean isTableExists(String namespace,String tablename) throws IOException {
       //获取admin
        Admin admin = connection.getAdmin();
        boolean b = false;
        try {
            b = admin.tableExists(TableName.valueOf(namespace, tablename));
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        admin.close();
        return b;
    }
    public static void createTable(String namespace,String tableName,String... columnFamilies) throws IOException {
        //判断列族
        if(columnFamilies.length == 0)
        {
            System.out.println("要求至少有一个列族");
            return;
        }
        //判断表格是否存在
        if(isTableExists(namespace,tableName))
        {
            System.out.println("表格已经存在");
            return;
        }
        //创建表格 columnFamilies列族名称,可有多个
        Admin admin = connection.getAdmin();
        //创建表格描述
        TableDescriptorBuilder tableDescriptorBuilder = TableDescriptorBuilder.newBuilder(TableName.valueOf(namespace, tableName));
        for(String columnFamily : columnFamilies) {
            ColumnFamilyDescriptorBuilder columnFamilyDescriptorBuilder = ColumnFamilyDescriptorBuilder.newBuilder(Bytes.toBytes(columnFamily));
            columnFamilyDescriptorBuilder.setMaxVersions(5);
            tableDescriptorBuilder.setColumnFamily(columnFamilyDescriptorBuilder.build());
        }
        try {
            admin.createTable(tableDescriptorBuilder.build());
        } catch (IOException e) {
            System.out.println("表格已经存在");
            throw new RuntimeException(e);
        }
        admin.close();

    }
    public static void modifyTable(String namespace,String tableName,String columnFamily,int version) throws IOException {
        if(!isTableExists(namespace,tableName))
        {
            return;
        }
        Admin admin = connection.getAdmin();

        try {
            TableDescriptor descriptor = admin.getDescriptor(TableName.valueOf(namespace, tableName));
            TableDescriptorBuilder tableDescriptorBuilder = TableDescriptorBuilder.newBuilder(descriptor);
            ColumnFamilyDescriptor columnFamily1 = descriptor.getColumnFamily(Bytes.toBytes(columnFamily));
            ColumnFamilyDescriptorBuilder columnFamilyDescriptorBuilder = ColumnFamilyDescriptorBuilder.newBuilder(columnFamily1);
            columnFamilyDescriptorBuilder.setMaxVersions(version);
            tableDescriptorBuilder.modifyColumnFamily(columnFamilyDescriptorBuilder.build());
            admin.modifyTable(tableDescriptorBuilder.build());
        } catch (IOException e) {
            throw new RuntimeException(e);
        }
        admin.close();
    }
    public static  boolean deleteTable(String namespace,String tablename) throws IOException {
        if(isTableExists(namespace,tablename))
        {
            System.out.println("表格不存在,无法删除");
            return false;
        }
        Admin admin = connection.getAdmin();

        try {
           TableName tableName1 = TableName.valueOf(namespace, tablename);
            admin.disableTable(tableName1);
            admin.deleteTable(tableName1);
        } catch (IOException e) {
            throw new RuntimeException(e);
        }

        admin.close();
        return true;
    }

    private static TableName getTableName(String namespace, String tablename) {
        return TableName.valueOf(namespace, tablename);
    }

    public static void main(String[] args) throws IOException {
        //测试命名空间
        //createNamespace("atguigu");
        //判断表格是否存在
        //System.out.println(isTableExists("bigdata", "student"));
        //创建表格
        createTable("atguigu","student","info1");
        //修改表格
        modifyTable("atguigu","student","info",6);
        System.out.println("其他代码");
        HbaseConection.closeConnection();
    }
}