Module: ActiveRecord::ConnectionAdapters::Jdbc::ArelSupport::ClassMethods

Defined in:
lib/arjdbc/jdbc/arel_support.rb

Instance Method Summary collapse

Instance Method Details

#arel_visitor_name(spec) ⇒ Object 



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# File 'lib/arjdbc/jdbc/arel_support.rb', line 13

def arel_visitor_name(spec)
  if spec
    if spec.respond_to?(:arel_visitor_name)
      spec.arel_visitor_name # for AREL built-in visitors
    else
      spec.name.split('::').last.downcase # ArJdbc::PostgreSQL -> postgresql
    end
  else # AR::ConnnectionAdapters::MySQLAdapter => mysql
    name.split('::').last.sub('Adapter', '').downcase
  end
end

#bind_substitution(visitor) ⇒ Class

Generates a class for the given visitor type, this new Class instance is a sub-class of Arel::Visitors::BindVisitor.

Returns:

  • (Class) —

    class for given visitor type



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# File 'lib/arjdbc/jdbc/arel_support.rb', line 89

def bind_substitution(visitor)
  # NOTE: similar convention as in AR (but no base substitution type) :
  # class BindSubstitution < ::Arel::Visitors::ToSql
  #   include ::Arel::Visitors::BindVisitor
  # end
  return const_get(:BindSubstitution) if const_defined?(:BindSubstitution)

  @@bind_substitutions ||= Java::JavaUtil::HashMap.new
  unless bind_visitor = @@bind_substitutions.get(visitor)
    @@bind_substitutions.synchronized do
      unless @@bind_substitutions.get(visitor)
        bind_visitor = Class.new(visitor) do
          include ::Arel::Visitors::BindVisitor
        end
        @@bind_substitutions.put(visitor, bind_visitor)
      end
    end
    bind_visitor = @@bind_substitutions.get(visitor)
  end
  bind_visitor
end

#resolve_visitor_type(config) ⇒ Object 



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# File 'lib/arjdbc/jdbc/arel_support.rb', line 32

def resolve_visitor_type(config)
  raise "missing :adapter in #{config.inspect}" unless adapter = config[:adapter]

  visitor_type = RESOLVED_VISITORS[ adapter ]

  if visitor_type.nil? || adapter == 'jdbc'
    if adapter_spec = config[:adapter_spec]
      if adapter_spec.respond_to?(:arel_visitor_type)
        visitor_type = adapter_spec.arel_visitor_type(config)
      elsif adapter_spec.respond_to?(:arel2_visitors) # backwards compat
        visitor_type = adapter_spec.arel2_visitors(config).values.first
      else # auto-convention ArJdbc::MySQL -> Arel::Visitors::MySQL
        const_name = adapter_spec.name.split('::').last
        visitor_type = ::Arel::Visitors.const_get(const_name) rescue nil
      end
    elsif respond_to?(:arel_visitor_type)
      visitor_type = arel_visitor_type(config) # adapter_class' override
    end

    if visitor_type && RESOLVED_VISITORS[ adapter ] # adapter == 'jdbc'
      if visitor_type != RESOLVED_VISITORS[ adapter ]
        ArJdbc.warn("overriding visitor for 'adapter: jdbc' (from #{RESOLVED_VISITORS[ adapter ]} to #{visitor_type})")
      end
    end

    visitor_type ||= ::Arel::Visitors::VISITORS[ arel_visitor_name(adapter_spec) ]
    visitor_type ||= ::Arel::Visitors::ToSql # default (if nothing resolved)

    RESOLVED_VISITORS.to_java.synchronized do
      RESOLVED_VISITORS[ adapter ] = ::Arel::Visitors::VISITORS[ adapter ] = visitor_type
    end
  end

  visitor_type
end

#visitor_for(pool) ⇒ Object

Note:

called from ActiveRecord::ConnectionAdapters::ConnectionPool.checkout (up till AR-3.2)



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# File 'lib/arjdbc/jdbc/arel_support.rb', line 78

def visitor_for(pool)
  visitor = resolve_visitor_type(config = pool.spec.config)
  ( prepared_statements?(config) ? visitor : bind_substitution(visitor) ).new(pool)
end