JavaScript--Promise(2)

阿新 • • 發佈：2020-12-06

ddl的操作

package com.bigdata.admin;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;

/**
 * namespace 的操作
 */
public class HBaseDemo01
{
    private Connection connection;
    @Before
    public void init() throws Exception {
        Configuration conf = HBaseConfiguration.create();
        conf.set("hbase.zookeeper.quorum","hadoop84:2181,hadoop85:2181,hadoop86:2181");
        connection = ConnectionFactory.createConnection(conf);
    }

    //create namespace
    @Test
    public void test01() throws IOException {
        Admin admin = connection.getAdmin();

        NamespaceDescriptor descriptor = NamespaceDescriptor.create("java_nameSpace").build();
        admin.createNamespace(descriptor);
        admin.close();
    }


    //list namespace
    @Test
    public void test02() throws IOException {
        Admin admin = connection.getAdmin();
        NamespaceDescriptor[] descriptors = admin.listNamespaceDescriptors();
        for (NamespaceDescriptor descriptor : descriptors) {
            System.out.println(descriptor.getName());
        }
        admin.close();
    }

    //list_namespace_tables
    @Test
    public void test03() throws IOException {
        Admin admin = connection.getAdmin();
        TableName[] defaults = admin.listTableNamesByNamespace("default");
        for (TableName tableName : defaults) {
            System.out.println(tableName.getNameAsString());
        }

        admin.close();
    }

    //describe_namespace
    @Test
    public void test04() throws IOException {
        Admin admin = connection.getAdmin();
        NamespaceDescriptor descriptor = admin.getNamespaceDescriptor("java_nameSpace");
        System.out.println(descriptor);

        admin.close();
    }
    //alter_namespace

    @Test
    public void test05() throws IOException {
        Admin admin = connection.getAdmin();
        NamespaceDescriptor descriptor = admin.getNamespaceDescriptor("java_nameSpace");
        descriptor.setConfiguration("author","wangWu");
        admin.modifyNamespace(descriptor);
        admin.close();
    }

    //drop_namespace

    @Test
    public void test06() throws IOException {
        Admin admin = connection.getAdmin();
        admin.deleteNamespace("java_nameSpace");
        admin.close();
    }
    @After
    public void close() throws IOException {
        connection.close();
    }
}

　#table的建立

package com.bigdata.admin;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.Admin;
import org.apache.hadoop.hbase.client.Connection;
import org.apache.hadoop.hbase.client.ConnectionFactory;
import org.apache.hadoop.hbase.client.Table;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.util.List;

/**
 * 
 */
public class HBaseDemo02
{
    private Connection connection;
    @Before
    public void init() throws Exception {
        Configuration conf = HBaseConfiguration.create();
        conf.set("hbase.zookeeper.quorum","hadoop84:2181,hadoop85:2181,hadoop86:2181");
        connection = ConnectionFactory.createConnection(conf);
    }

    //create table
    @Test
    public void test01() throws IOException {
        Admin admin = connection.getAdmin();

        HTableDescriptor descriptor = new HTableDescriptor(TableName.valueOf("t_java01"));

        HColumnDescriptor hColumnDescriptor = new HColumnDescriptor("cf01");
        descriptor.addFamily(hColumnDescriptor);//新增列族
        admin.createTable(descriptor);
        admin.close();
    }
    //create table--分割槽
    @Test
    public void test02() throws IOException {
        Admin admin = connection.getAdmin();

        HTableDescriptor descriptor = new HTableDescriptor(TableName.valueOf("t_java02"));

        HColumnDescriptor hColumnDescriptor = new HColumnDescriptor("cf01");
        descriptor.addFamily(hColumnDescriptor);//新增列族
        byte[][] splitKeys={"10".getBytes(),"20".getBytes()};
        admin.createTable(descriptor,splitKeys);
        admin.close();
    }

    //建表-預分割槽
    @Test
    public void test03() throws IOException {
        Admin admin = connection.getAdmin();

        TableName tableName = TableName.valueOf("t_java003");
        HTableDescriptor descriptor = new HTableDescriptor(tableName);

        HColumnDescriptor hColumnDescriptor = new HColumnDescriptor("cf02");
        descriptor.addFamily(hColumnDescriptor);

        admin.createTable(descriptor,"10".getBytes(),"30".getBytes(),3);

        admin.close();
    }
    //describe
    @Test
    public void test04() throws IOException {
        Admin admin = connection.getAdmin();

        HTableDescriptor descriptor = admin.getTableDescriptor(TableName.valueOf("t2"));
        System.out.println(descriptor);

        admin.close();
    }

    //exists
    //禁用
    //刪除表
    @Test
    public void test05() throws IOException {
        Admin admin = connection.getAdmin();
        TableName tableName = TableName.valueOf("t_java02");
        boolean b = admin.tableExists(tableName);
        if(b){
            admin.disableTable(tableName);//禁用
            admin.deleteTable(tableName);//刪除表
        }

        admin.close();
    }

    //list
    @Test
    public void test06() throws IOException {
        Admin admin = connection.getAdmin();
        //TableName tableName = TableName.valueOf("t_java");
        TableName[] tableNames = admin.listTableNames();
        for (TableName name : tableNames) {
            System.out.println(name.getNameAsString());
        }

        admin.close();
    }

    //list_regions
    @Test
    public void test07() throws IOException {
        Admin admin = connection.getAdmin();
        List<HRegionInfo> regions = admin.getTableRegions(TableName.valueOf("t_java003"));
        for (HRegionInfo region : regions) {
            System.out.println(region);
        }
        admin.close();
    }
    //alter
    @Test
    public void test08() throws IOException {
        Admin admin = connection.getAdmin();
        TableName tableName = TableName.valueOf("t_java003");
        HTableDescriptor descriptor = new HTableDescriptor(tableName);
        HColumnDescriptor columnDescriptor = new HColumnDescriptor("cf01");
        descriptor.addFamily(columnDescriptor);
        columnDescriptor.setVersions(1,5);
        admin.modifyTable(tableName,descriptor);
        admin.close();
    }
    @After
    public void close() throws IOException {
        connection.close();
    }
}

　　#table的操作

package com.bigdata.table;


import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.*;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.util.ArrayList;
import java.util.Iterator;
import java.util.List;

/**
 * @version 1.0
 * @name mir zhou
 * @date 2020/12/2 10:15
 * @function table 的操作
 * @return
 */
public class HBaseDemo03
{
    private Connection connection;
    @Before
    public void init() throws Exception {
        Configuration conf = HBaseConfiguration.create();
        conf.set("hbase.zookeeper.quorum","hadoop84:2181,hadoop85:2181,hadoop86:2181");
        connection = ConnectionFactory.createConnection(conf);
    }
    //get
    @Test
    public void test01() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Get get = new Get(Bytes.toBytes("1001"));
        Result result = table.get(get);
        List<Cell> cells = result.listCells();
        for (Cell cell : cells) {
            System.out.println(Bytes.toString(CellUtil.cloneValue(cell)));
            System.out.println(Bytes.toString(CellUtil.cloneRow(cell)));
            System.out.println("--------------");
        }
        table.close();
    }

    //get 指定列
    @Test
    public void test001() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Get get = new Get(Bytes.toBytes("1001"));
        get.addColumn(Bytes.toBytes("cf01"),Bytes.toBytes("name"));
        Result result = table.get(get);
        List<Cell> cells = result.listCells();
        for (Cell cell : cells) {
            System.out.println(Bytes.toString(CellUtil.cloneValue(cell)));
            System.out.println(Bytes.toString(CellUtil.cloneRow(cell)));

        }
        table.close();
    }

    //scan 掃描所有 慎用
    @Test
    public void test02() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Scan scan = new Scan();
        ResultScanner scanner = table.getScanner(scan);
        Iterator<Result> iterator = scanner.iterator();

        while(iterator.hasNext()){
            Result result = iterator.next();
            List<Cell> cells = result.listCells();
            for (Cell cell : cells) {
                System.out.println(Bytes.toString(CellUtil.cloneValue(cell)));
                System.out.println(Bytes.toString(CellUtil.cloneRow(cell)));
                System.out.println("=---------------");
            }
        }
        table.close();
    }

    //scan 指定掃描
    @Test
    public void test03() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Scan scan = new Scan();
        scan.withStartRow(Bytes.toBytes("1001"));
        scan.withStopRow(Bytes.toBytes("1002")); //包左不包右
       // scan.setOneRowLimit()
        scan.setRaw(true);//開啟raw模式  會掃描添加了刪除標記的，但未真正刪除的
        ResultScanner scanner = table.getScanner(scan);

//        for (Result result : scanner) {
//
//        }
        Iterator<Result> iterator = scanner.iterator();

        while(iterator.hasNext()){
            Result result = iterator.next();
            List<Cell> cells = result.listCells();
            for (Cell cell : cells) {
                System.out.println(Bytes.toString(CellUtil.cloneValue(cell)));
                System.out.println(Bytes.toString(CellUtil.cloneRow(cell)));
                System.out.println(Bytes.toString(CellUtil.cloneQualifier(cell)));
                System.out.println("---------------");
            }
        }
        table.close();
    }

    // put Mutation
    @Test
    public void test04() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Put put = new Put(Bytes.toBytes("1004")); //可以新增多條
        put.addColumn(Bytes.toBytes("cf01"),Bytes.toBytes("phone"),Bytes.toBytes("11111111"));
        put.addColumn(Bytes.toBytes("cf01"),Bytes.toBytes("qq"),Bytes.toBytes("12211111"));

        table.put(put);
        table.close();
    }
    //append
    @Test
    public void test05() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Append append = new Append(Bytes.toBytes("1004")); //指定rowkey
        append.add(Bytes.toBytes("cf01"),Bytes.toBytes("phone"),Bytes.toBytes("_11111111"));
        Result result = table.append(append);
        List<Cell> cells = result.listCells();
        for (Cell cell : cells) {
            System.out.println(Bytes.toString(CellUtil.cloneValue(cell)));
        }
        table.close();
    }

    //delete
    @Test
    public void test06() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Delete delete = new Delete(Bytes.toBytes("1004")); //指定rowKey
       // delete.addFamily(Bytes.toBytes("cf01"));//指定cf
        delete.addColumn(Bytes.toBytes("cf01"),Bytes.toBytes("phone"));//指定col 和列限定符(qualifier)
        table.delete(delete);
        table.close();
    }
    @After
    public void close() throws IOException {
        connection.close();
    }
}

　　#過濾器的使用

package com.bigdata.table;

import org.apache.hadoop.conf.Configuration;
import org.apache.hadoop.hbase.Cell;
import org.apache.hadoop.hbase.CellUtil;
import org.apache.hadoop.hbase.HBaseConfiguration;
import org.apache.hadoop.hbase.TableName;
import org.apache.hadoop.hbase.client.*;
import org.apache.hadoop.hbase.filter.BinaryPrefixComparator;
import org.apache.hadoop.hbase.filter.CompareFilter;
import org.apache.hadoop.hbase.filter.SingleColumnValueFilter;
import org.apache.hadoop.hbase.filter.SubstringComparator;
import org.apache.hadoop.hbase.util.Bytes;
import org.junit.After;
import org.junit.Before;
import org.junit.Test;

import java.io.IOException;
import java.util.Iterator;
import java.util.List;


/**
 * @version 1.0
 * @name mir zhou
 * @date 2020/12/2 14:32
 * @function
 * @return
 */
public class HBaseDemo04
{
    private Connection connection;
    @Before
    public void init() throws Exception {
        Configuration conf = HBaseConfiguration.create();
        conf.set("hbase.zookeeper.quorum","hadoop84:2181,hadoop85:2181,hadoop86:2181");
        connection = ConnectionFactory.createConnection(conf);
    }
    //age > 20
    @Test
    public void test02() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Scan scan = new Scan();
        SingleColumnValueFilter filter = new SingleColumnValueFilter(
                Bytes.toBytes("cf01"),
                Bytes.toBytes("age"),
                CompareFilter.CompareOp.GREATER,
                Bytes.toBytes("20")
        );
        filter.setFilterIfMissing(true); //如果沒有age欄位就過濾掉
        scan.setFilter(filter);
        ResultScanner scanner = table.getScanner(scan);
        for (Result result : scanner) {
            List<Cell> cells = result.listCells();
            for (Cell cell : cells) {
                System.out.println(Bytes.toString(CellUtil.cloneRow(cell)));
            }
        }

        table.close();
    }

    //name  zh打頭 or 含有 g
    @Test
    public void test03() throws IOException {
        Table table = connection.getTable(TableName.valueOf("t2"));
        Scan scan = new Scan();

        SingleColumnValueFilter filter = new SingleColumnValueFilter(
                Bytes.toBytes("cf01"),
                Bytes.toBytes("name"),
                CompareFilter.CompareOp.EQUAL,
                new BinaryPrefixComparator(Bytes.toBytes("zh"))
                //new SubstringComparator("g") //含有g
        );

        filter.setFilterIfMissing(true); //如果沒有age欄位就過濾掉。
        scan.setFilter(filter);

        ResultScanner scanner = table.getScanner(scan);
        for (Result result : scanner) {
            List<Cell> cells = result.listCells();
            for (Cell cell : cells) {
                System.out.println(Bytes.toString(CellUtil.cloneRow(cell)));
            }
        }
        table.close();
    }
    @After
    public void close() throws IOException {
        connection.close();
    }
}

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