hbase 查看元数据

package com.jason.lala.pipe.dbinfo

import com.jason.lala.common.query.option.HbaseOptions
import org.apache.hadoop.hbase.{CellUtil, HBaseConfiguration, TableName}
import org.apache.hadoop.hbase.client.{Connection, ConnectionFactory, HTable, Scan}
import org.apache.hadoop.hbase.filter.PageFilter
import org.apache.hadoop.hbase.util.Bytes

class HbaseShow(private val map: Map[String, String]) {
  private val con = HbaseShow.getCon
  private val hBaseAdmin = con.getAdmin
  private val nameSpace = map.getOrElse(HbaseOptions.NAMESPACE, "")
  private val tbl = map.getOrElse(HbaseOptions.TBL, "")
  private val cf = map.getOrElse(HbaseOptions.CF, "")
  private val hbaseTable = s"${nameSpace}:${tbl}"

  /**
    * 获取hbase 中的namespaces
    *
    * @return
    */
  def getNamespaces: String = {
    val tableNames = hBaseAdmin.listTableNames
    val arrString = for {
      tableName <- tableNames
      arr = tableName.getNameAsString.split(":", )
    } yield {
      arr()
    }
    arrString.toSet.mkString(",")
  }

  /**
    * 获取对应namespace 下的tablenames
    *
    * @return
    */
  def getTableNames(): String = {
    val tableNames = hBaseAdmin.listTableNames
    val arrString = for {
      tableName <- tableNames
      arr = tableName.getNameAsString.split(":", )
      if arr() == nameSpace
    } yield {
      arr()
    }
    arrString.mkString(",")
  }

  def getColumnsWithCF(): String = getColumnsWithCF().mkString(",")

  def getColumns(): String = getColumns().mkString(",")

  /**
    * namespace:colname,namespace2:colname2
    *
    * @param limitScan
    * @return
    */
  private def getColumnsWithCF(limitScan: Int): Array[String] = {
    val columnList = scala.collection.mutable.TreeSet[String]()
    //val hTable = new HTable(hBaseConfiguration, hbaseTable)
    val hTable = con.getTable(TableName.valueOf(hbaseTable))
    val scan = new Scan
    scan.setFilter(new PageFilter(limitScan))
    val results = hTable.getScanner(scan)
    import scala.collection.JavaConversions._

    //========================
    for (result <- results) {
      for (cell <- result.listCells()) {
        val family = Bytes.toString(CellUtil.cloneFamily(cell))
        val qualifier = Bytes.toString(CellUtil.cloneQualifier(cell))
        columnList.add(s"$family:$qualifier")
      }
    }

    //========================
    Array("rowkey:key1") ++ (columnList.toArray[String])
  }

  /**
    * colname,colname2...
    *
    * @param limitScan
    * @return
    */
  private def getColumns(limitScan: Int): Array[String] = {
    val columnList = getColumnsWithCF(limitScan)
    val list = columnList.filter {
      s =>
        val arr = s.split(":", )
        arr() == cf
    }.map(_.split(":", )())
    list
  }

  def getCfs(): String = {
    val htd = hBaseAdmin.getTableDescriptor(TableName.valueOf(hbaseTable))
    val cfs = for (cf <- htd.getColumnFamilies) yield {
      cf.getNameAsString
    }
    cfs.mkString(",")
  }

  /**
    *
    * @param limitScan
    * @return
    */
  def getSampleData(limitScan: Long = DBShow.Num): String = {
    val hTable = con.getTable(TableName.valueOf(hbaseTable))
    val scan = new Scan
    scan.setFilter(new PageFilter(limitScan))
    val results = hTable.getScanner(scan)
    import scala.collection.JavaConversions._
    val sample = for {
      result <- results
      cell <- result.listCells()
    } yield {
      //取行健
      val rowKey = Bytes.toString(CellUtil.cloneRow(cell));
      //取到时间戳
      val timestamp = cell.getTimestamp();
      //取到族列
      val family = Bytes.toString(CellUtil.cloneFamily(cell));
      //取到修饰名
      val qualifier = Bytes.toString(CellUtil.cloneQualifier(cell));
      //取到值
      val value = Bytes.toString(CellUtil.cloneValue(cell));
      //stu1                        column=course:english, timestamp=1544063446429, value=90
      s"$rowKey, column=$family:$qualifier, timestamp=$timestamp, value=${value}"

    }
    sample.mkString("\n")
  }

}

object HbaseShow {
  private var conn: Connection = null

  def getCon: Connection = {
    if (conn == null) {
      val hBaseConfiguration = HBaseConfiguration.create()
      conn = ConnectionFactory.createConnection(hBaseConfiguration)
    }
    conn
  }
}