Hbase 的javaAPI基本操作用 在idea上的实现

1.保证集群开启：

jps有如下进程

2.pom文件中的依赖

<?xml version="1.0" encoding="UTF-8"?>
<project xmlns="http://maven.apache.org/POM/4.0.0"
         xmlns:xsi="http://www.w3.org/2001/XMLSchema-instance"
         xsi:schemaLocation="http://maven.apache.org/POM/4.0.0 http://maven.apache.org/xsd/maven-4.0.0.xsd">
    <modelVersion>4.0.0</modelVersion>

    <groupId>com.zhiyou100</groupId>
    <artifactId>hbasedemo</artifactId>
    <version>1.0-SNAPSHOT</version>

    <properties>
        <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding>
        <hbase.version>1.4.8</hbase.version>
    </properties>

    <dependencies>
        <!--hbase-->
        <dependency>
            <groupId>org.apache.hbase</groupId>
            <artifactId>hbase-client</artifactId>
            <version>${hbase.version}</version>
        </dependency>
        <dependency>
            <groupId>org.apache.hbase</groupId>
            <artifactId>hbase-common</artifactId>
            <version>${hbase.version}</version>
        </dependency>
        <!--要使用HBase的MapReduce API-->
        <dependency>
            <groupId>org.apache.hbase</groupId>
            <artifactId>hbase-server</artifactId>
            <version>${hbase.version}</version>
        </dependency>
    </dependencies>
    
</project>

3.编写配置文件：hbase-site.xml

将集群上$HBASE_HOME/conf/hbase-site.xml拷贝过来就可以，也可以直接复制下面内容

<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>
<!--
/**
 *
 * Licensed to the Apache Software Foundation (ASF) under one
 * or more contributor license agreements.  See the NOTICE file
 * distributed with this work for additional information
 * regarding copyright ownership.  The ASF licenses this file
 * to you under the Apache License, Version 2.0 (the
 * "License"); you may not use this file except in compliance
 * with the License.  You may obtain a copy of the License at
 *
 *     http://www.apache.org/licenses/LICENSE-2.0
 *
 * Unless required by applicable law or agreed to in writing, software
 * distributed under the License is distributed on an "AS IS" BASIS,
 * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 * See the License for the specific language governing permissions and
 * limitations under the License.
 */
-->
<configuration>
    <property>
        <name>hbase.rootdir</name>
        <value>hdfs://master2:9000/hbase</value>
    </property>
    <property>
        <name>hbase.cluster.distributed</name>
        <value>true</value>
    </property>
<!--conf.set("hbase.zookeeper.quorum", "master2");-->
    <!--// 设置Zookeeper,直接设置IP地址-->
    <property>
        <name>hbase.zookeeper.quorum</name>
        <value>master2</value>
    </property>

</configuration>

---注意：如果没有再本地的C:WindowsSystem32driversetc路径下的hosts文件中配置IP 与之对应的主机名

请将上面的主机名（master2）填写成自己的IP

4.编写java代码--创建类：HBaseDDL

package com.hbase.DDL;

import com.google.common.io.Resources;
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.*;
import org.apache.hadoop.hbase.util.Bytes;

import java.io.IOException;

public class HBaseDDL {
    private static Configuration configuration;
    private static Connection connection;
    private static Admin admin;
    static {
        //1.获得Configuration实例并进行相关设置
        configuration = HBaseConfiguration.create();
        configuration.addResource(Resources.getResource("hbase-site.xml"));
        //2.获得Connection实例
        try {
            connection = ConnectionFactory.createConnection(configuration);
            //3.1获得Admin接口
            admin = connection.getAdmin();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }
    public static void main(String[] args) throws IOException {
        //创建表
        String  familyNames[]={"nature","social"};
        createTable("test_hbase",familyNames);
        //向表中插入数据
        insert("test_hbase","libai","nature","height","25");
        //删除表
        dropTable("test_hbase");
    }
    /**
     * 创建表
     * @param tableName 表名
     * @param familyNames 列族名
     * */
    public static void createTable(String tableName, String familyNames[]) throws IOException {
        //如果表存在退出
        if (admin.tableExists(TableName.valueOf(tableName))) {
            System.out.println("Table exists!");
            return;
        }
        //通过HTableDescriptor类来描述一个表，HColumnDescriptor描述一个列族
        HTableDescriptor tableDescriptor = new HTableDescriptor(TableName.valueOf(tableName));
        for (String familyName : familyNames) {
            tableDescriptor.addFamily(new HColumnDescriptor(familyName));
        }
        //tableDescriptor.addFamily(new HColumnDescriptor(familyName));
        admin.createTable(tableDescriptor);
        System.out.println("createtable success!");
    }

    /**
     * 删除表
     * @param tableName 表名
     * */
    public static void dropTable(String tableName) throws IOException {
        //如果表不存在报异常
        if (!admin.tableExists(TableName.valueOf(tableName))) {
            System.out.println(tableName+"不存在");
            return;
        }

        //删除之前要将表disable
        if (!admin.isTableDisabled(TableName.valueOf(tableName))) {
            admin.disableTable(TableName.valueOf(tableName));
        }
        admin.deleteTable(TableName.valueOf(tableName));
        System.out.println("deletetable " + tableName + "ok.");
    }

    /**
     * 指定行/列中插入数据
     * @param tableName 表名
     * @param rowKey 主键rowkey
     * @param family 列族
     * @param column 列
     * @param value 值
     * TODO: 批量PUT
     */
    public static void insert(String tableName, String rowKey, String family, String column, String value) throws IOException {
        //3.2获得Table接口,需要传入表名
        Table table =connection.getTable(TableName.valueOf(tableName));
        Put put = new Put(Bytes.toBytes(rowKey));
        put.addColumn(Bytes.toBytes(family), Bytes.toBytes(column), Bytes.toBytes(value));
        table.put(put);
        System.out.println("insertrecored " + rowKey + " totable " + tableName + "ok.");
    }

    /**
     * 删除表中的指定行
     * @param tableName 表名
     * @param rowKey rowkey
     * TODO: 批量删除
     */
    public static void delete(String tableName, String rowKey) throws IOException {
        //3.2获得Table接口,需要传入表名
        Table table = connection.getTable(TableName.valueOf(tableName));
        Delete delete = new Delete(Bytes.toBytes(rowKey));
        table.delete(delete);
    }
}

测试：1.创建表-----createTable("test_hbase",familyNames);

在hbase shell中list查看表

---

2.向创建的表中插入数据-----insert("test_hbase","luban","nature","height","250");

在hbase shell中scan 'test_hbase'查看表内容

---

3.删除表------dropTable("test_hbase");

在hbase shell中list查看表,已经没有了test_hbase