Convert JDBC ResultSet into Ruby Hash with JRuby

jdbc_sample.rb

require 'java'
require 'jt400'
require 'date'
require 'bigdecimal'

java_import 'com.ibm.as400.access.AS400JDBCDriver'

def get_records
  @connection ||= java.sql.DriverManager.get_connection("jdbc:as400://127.0.0.1/",'username','password')
  rs = @connection.createStatement.executeQuery("SELECT * FROM RANDOM_TABLE")
  puts resultset_to_hash(rs).inspect
end

def resultset_to_hash(resultset)
  meta = resultset.meta_data
  rows = []

  while resultset.next
    row = {}

    (1..meta.column_count).each do |i|
      name = meta.column_name i
      row[name]  =  case meta.column_type(i)
                    when -6, -5, 5, 4
                      # TINYINT, BIGINT, INTEGER
                      resultset.get_int(i).to_i
                    when 41
                      # Date
                      resultset.get_date(i)
                    when 92
                      # Time
                      resultset.get_time(i).to_i
                    when 93
                      # Timestamp
                      resultset.get_timestamp(i)
                    when 2, 3, 6
                      # NUMERIC, DECIMAL, FLOAT
                      case meta.scale(i)
                      when 0
                        resultset.get_long(i).to_i
                      else
                        BigDecimal.new(resultset.get_string(i).to_s)
                      end
                    when 1, -15, -9, 12
                      # CHAR, NCHAR, NVARCHAR, VARCHAR
                      resultset.get_string(i).to_s
                    else
                      resultset.get_string(i).to_s
                    end
    end

    rows << row
  end
  rows
end

Your code for converting resultset to hash helped a lot. I have a JRuby+Sinatra+AS400 example @ http://opensourcetips.blogspot.com/2014/09/datatablesnet-jruby-sinatra.html

It's amazing to me that this code still works, a dozen years later!

I just had to update two things:

• change meta.column_name to meta.get_column_name
• change meta.column_type to meta.get_column_type

Thank you, @rwjblue !