HBaseAPI

环境准备

新建项目后在pom.xml中添加依赖:

<dependency>
    <groupId>org.apache.hbase</groupId>
    <artifactId>hbase-server</artifactId>
    <version>1.3.1</version>
</dependency>

<dependency>
    <groupId>org.apache.hbase</groupId>
    <artifactId>hbase-client</artifactId>
    <version>1.3.1</version>
</dependency>

<dependency>
    <groupId>jdk.tools</groupId>
    <artifactId>jdk.tools</artifactId>
    <version>1.8</version>
    <scope>system</scope>
    <systemPath>${JAVA_HOME}/lib/tools.jar</systemPath>
</dependency>

HBaseAPI

获取Configuration对象

public static Configuration conf;

static{

    //使用HBaseConfiguration的单例方法实例化

    conf = HBaseConfiguration.create();

conf.set("hbase.zookeeper.quorum", "192.168.9.102");

conf.set("hbase.zookeeper.property.clientPort", "2181");

}

 判断表是否存在

public static boolean isTableExist(String tableName) throws MasterNotRunningException,

 ZooKeeperConnectionException, IOException{

    //在HBase中管理、访问表需要先创建HBaseAdmin对象

//Connection connection = ConnectionFactory.createConnection(conf);

//HBaseAdmin admin = (HBaseAdmin) connection.getAdmin();

    HBaseAdmin admin = new HBaseAdmin(conf);

    return admin.tableExists(tableName);

}

创建表

public static void createTable(String tableName, String... columnFamily) throws

 MasterNotRunningException, ZooKeeperConnectionException, IOException{

    HBaseAdmin admin = new HBaseAdmin(conf);

    //判断表是否存在

    if(isTableExist(tableName)){

       System.out.println("表" + tableName + "已存在");

       //System.exit(0);

    }else{

       //创建表属性对象,表名需要转字节

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

       //创建多个列族

       for(String cf : columnFamily){

           descriptor.addFamily(new HColumnDescriptor(cf));

       }

       //根据对表的配置,创建表

       admin.createTable(descriptor);

       System.out.println("表" + tableName + "创建成功!");

    }

}

删除表

public static void dropTable(String tableName) throws MasterNotRunningException,

 ZooKeeperConnectionException, IOException{

    HBaseAdmin admin = new HBaseAdmin(conf);

    if(isTableExist(tableName)){

       admin.disableTable(tableName);

       admin.deleteTable(tableName);

       System.out.println("表" + tableName + "删除成功!");

    }else{

       System.out.println("表" + tableName + "不存在!");

    }

}

向表中插入数据

public static void addRowData(String tableName, String rowKey, String columnFamily, String

 column, String value) throws IOException{

    //创建HTable对象

    HTable hTable = new HTable(conf, tableName);

    //向表中插入数据

    Put put = new Put(Bytes.toBytes(rowKey));

    //向Put对象中组装数据

    put.add(Bytes.toBytes(columnFamily), Bytes.toBytes(column), Bytes.toBytes(value));

    hTable.put(put);

    hTable.close();

    System.out.println("插入数据成功");

}

 删除多行数据

public static void deleteMultiRow(String tableName, String... rows) throws IOException{

    HTable hTable = new HTable(conf, tableName);

    List<Delete> deleteList = new ArrayList<Delete>();

    for(String row : rows){

       Delete delete = new Delete(Bytes.toBytes(row));

       deleteList.add(delete);

    }

    hTable.delete(deleteList);

    hTable.close();

}

6.2.7 获取所有数据

public static void getAllRows(String tableName) throws IOException{

    HTable hTable = new HTable(conf, tableName);

    //得到用于扫描region的对象

    Scan scan = new Scan();

    //使用HTable得到resultcanner实现类的对象

    ResultScanner resultScanner = hTable.getScanner(scan);

    for(Result result : resultScanner){

       Cell[] cells = result.rawCells();

       for(Cell cell : cells){

           //得到rowkey

           System.out.println("行键:" + Bytes.toString(CellUtil.cloneRow(cell)));

           //得到列族

           System.out.println("列族" + Bytes.toString(CellUtil.cloneFamily(cell)));

           System.out.println("列:" + Bytes.toString(CellUtil.cloneQualifier(cell)));

           System.out.println("值:" + Bytes.toString(CellUtil.cloneValue(cell)));

       }

    }

}

6.2.8 获取某一行数据

public static void getRow(String tableName, String rowKey) throws IOException{

    HTable table = new HTable(conf, tableName);

    Get get = new Get(Bytes.toBytes(rowKey));

    //get.setMaxVersions();显示所有版本

    //get.setTimeStamp();显示指定时间戳的版本

    Result result = table.get(get);

    for(Cell cell : result.rawCells()){

       System.out.println("行键:" + Bytes.toString(result.getRow()));

       System.out.println("列族" + Bytes.toString(CellUtil.cloneFamily(cell)));

       System.out.println("列:" + Bytes.toString(CellUtil.cloneQualifier(cell)));

       System.out.println("值:" + Bytes.toString(CellUtil.cloneValue(cell)));

       System.out.println("时间戳:" + cell.getTimestamp());

    }

}

6.2.9 获取某一行指定“列族:列”的数据

public static void getRowQualifier(String tableName, String rowKey, String family, String

 qualifier) throws IOException{

    HTable table = new HTable(conf, tableName);

    Get get = new Get(Bytes.toBytes(rowKey));

    get.addColumn(Bytes.toBytes(family), Bytes.toBytes(qualifier));

    Result result = table.get(get);

    for(Cell cell : result.rawCells()){

       System.out.println("行键:" + Bytes.toString(result.getRow()));

       System.out.println("列族" + Bytes.toString(CellUtil.cloneFamily(cell)));

       System.out.println("列:" + Bytes.toString(CellUtil.cloneQualifier(cell)));

       System.out.println("值:" + Bytes.toString(CellUtil.cloneValue(cell)));

    }

}

HBaseAPI

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