Hbase-day03-API操作

package com.atguigu.test;

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.apache.hadoop.yarn.webapp.hamlet.Hamlet;

import java.io.IOException;

/**
 *
 * ddl
 * 1:判断表是否存在
 * 2:创建表
 * 3：创建命名空间
 * 4：删除表
 *
 * dml
 * 1:插入数据
 * 2:查数据（get）
 * 3：查数据（scan）
 * 4：删除数据
 *
 */
public class TestAPI {

    private static Connection connection = null;
    private static Admin admin = null;

    static {
        try {
            //1.获取配置信息
            Configuration configuration = HBaseConfiguration.create();
            configuration.set("hbase.zookeeper.quorum","hadoop102,hadoop103,hadoop104");

            //2.创建连接对象
            connection = ConnectionFactory.createConnection(configuration);

            //3.创建admin对象
            admin = connection.getAdmin();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

    //1.判断表是否存在
    public static boolean isTableExist(String tableName) throws IOException {

        /*//1.获取配置信息
        //HBaseConfiguration configuration = new HBaseConfiguration();

        Configuration configuration = HBaseConfiguration.create();
        configuration.set("hbase.zookeeper.quorum","hadoop102,hadoop103,hadoop104");

        //2.获取管理员对象
        //HBaseAdmin admin = new HBaseAdmin(configuration);
        Connection connection = ConnectionFactory.createConnection(configuration);
        Admin admin = connection.getAdmin();


        //3.判断表是否存在
        //boolean exists = admin.tableExists(tableName);*/
        boolean exists = admin.tableExists(TableName.valueOf(tableName));

        //4.关闭连接
     //  admin.close();

        //5.返回结果
        return exists;
    }

    //2.创建表
    public static void createTable(String tableName,String... cfs) throws IOException {

        //1.判断是否存在列族信息
        if(cfs.length <= 0){
            System.out.println("请设置列族信息");
            return;
        }

        //2.判断表是否存在
        if(isTableExist(tableName)){
            System.out.println(tableName+"表已存在！");
            return;
        }

        //3.创建表描述器
        HTableDescriptor hTableDescriptor = new HTableDescriptor(TableName.valueOf(tableName));

        //4.循环添加列族信息
        for (String cf : cfs) {

            //5.创建列族描述器
            HColumnDescriptor hColumnDescriptor = new HColumnDescriptor(cf);

            //6.添加具体的列族信息
            hTableDescriptor.addFamily(hColumnDescriptor);

        }

        //7.创建表
        admin.createTable(hTableDescriptor);

    }

    //3.删除表
    public static void dropTable(String tableName) throws IOException {

        //1.判断表是否存在
        if(!isTableExist(tableName)){
            System.out.println(tableName+"表不存在！");
            return;
        }

        //2.使表下线
        admin.disableTable(TableName.valueOf(tableName));

        //3.删除表
        admin.deleteTable(TableName.valueOf(tableName));

    }

    //4.创建命名空间
    public static void createNameSpace(String ns){

        //1.创建命名空间描述器
        NamespaceDescriptor namespaceDescriptor = NamespaceDescriptor.create(ns).build();

        //2.创建命名空间
        try {
            admin.createNamespace(namespaceDescriptor);
        }catch (NamespaceExistException e){
            System.out.println(ns+"命名空间已存在");
        } catch (IOException e) {
            e.printStackTrace();
        }

        System.out.println("尽管存在，依然可以显示");
    }

    //5.向表插入数据
    public static void putData(String tableName,String rowKey,String cf,String cn,String value) throws IOException {

        //1.获取表对象
        Table table = connection.getTable(TableName.valueOf(tableName));

        //2.创建put对象
        Put put = new Put(Bytes.toBytes(rowKey));

        //3.给put对象赋值
        put.addColumn(Bytes.toBytes(cf), Bytes.toBytes(cn),Bytes.toBytes(value));

        //4.插入数据
        table.put(put);

        //5.关闭表连接
        table.close();
    }

    //6.获取数据
    public static void getData(String tableName,String rowKey,String cf,String cn) throws IOException {

        //1.获取表对象
        Table table = connection.getTable(TableName.valueOf(tableName));

        //2.创建get对象
        Get get = new Get(Bytes.toBytes(rowKey));

        //2.1指定获取的列族
        get.addFamily(Bytes.toBytes(cf));

        //2.2指定列族和列
        get.addColumn(Bytes.toBytes(cf),Bytes.toBytes(cn));

        //3.获取数据
        Result result = table.get(get);

        //4.解析result并打印
        for (Cell cell : result.rawCells()) {

            //5.打印数据
            System.out.println("CF"+Bytes.toString(CellUtil.cloneFamily(cell))+"CN"+Bytes.toString(CellUtil.cloneQualifier(cell))+"VALUE"+Bytes.toString(CellUtil.cloneValue(cell)));
        }

        //6.关闭表连接
        table.close();
    }

    //7.获取数据（Scan）
    public static void scanTable(String tableName) throws IOException {

        //1.获取表对象
        Table table = connection.getTable(TableName.valueOf(tableName));

        //2.获取scan对象
        Scan scan = new Scan();

        //3.扫描表
        ResultScanner resultScanner = table.getScanner(scan);

        //4.解析resultScanner
        for (Result result : resultScanner) {
            //5.解析result并打印
            for (Cell cell : result.rawCells()) {
                //6.打印数据
                System.out.println("CF"+Bytes.toString(CellUtil.cloneFamily(cell))+"CN"+Bytes.toString(CellUtil.cloneQualifier(cell))+"VALUE"+Bytes.toString(CellUtil.cloneValue(cell)));
            }
        }

        //7.关闭连接
        table.close();
    }

    //8.删除数据
    public static void deleteData(String tableName,String rowKey,String cf,String cn) throws IOException {

        //1.获取表对象
        Table table = connection.getTable(TableName.valueOf(tableName));

        //2.构建删除对象
        Delete delete = new Delete(Bytes.toBytes(rowKey));

        //2.1:设置删除的列
        delete.addColumn()

        //3.执行删除操作
        table.delete(delete);

        //4.关闭连接
        table.close();

    }

    public static void close(){
        if (admin != null){
            try {
                admin.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }

        if (connection != null){
            try {
                connection.close();
            } catch (IOException e) {
                e.printStackTrace();
            }
        }
    }

    public static void main(String[] args) throws IOException {

        //1.测试是否存在
        System.out.println(isTableExist("stu5"));

        //2.创建表测试
        createTable("stu5","info1","info2");

        System.out.println(isTableExist("stu5"));

        //3.删除表测试
        dropTable("stu5");

        System.out.println(isTableExist("stu5"));

        //4.创建命名空间测试
        createNameSpace("0408");

        //5.创建数据测试
        putData("stu","1001","info2","name","zhangsan");

        //6.获取单行数据
        getData("stu","1002","info2","asas");

        //7.测试并扫描数据
        scanTable("stu");

        //8.删除
        deleteData("stu","1005","info","asas");
        //关闭资源
        close();

    }

}