hbase-shell/src/main/ruby/shell/commands/get_counter.rb

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module Shell
  module Commands
    class GetCounter < Command
      def help
        return <<-EOF
Return a counter cell value at specified table/row/column coordinates.
A counter cell should be managed with atomic increment functions on HBase
and the data should be binary encoded (as long value). Example:

  hbase> get_counter 'ns1:t1', 'r1', 'c1'
  hbase> get_counter 't1', 'r1', 'c1'

The same commands also can be run on a table reference. Suppose you had a reference
t to table 't1', the corresponding command would be:

  hbase> t.get_counter 'r1', 'c1'
EOF
      end

      def command(table, row, column)
        get_counter(table(table), row, column)
      end

      def get_counter(table, row, column)
        if cnt = table._get_counter_internal(row, column)
          puts "COUNTER VALUE = #{cnt}"
        else
          puts "No counter found at specified coordinates"
        end
      end
    end
  end
end

::Hbase::Table.add_shell_command('get_counter')