Storing an array of objects

Question

I am trying to store an array of objects;

class ColumnMapping
    @@column = nil
    @@method = nil

    def initialize(col, meth)
        @@column = col
        @@method = meth
    end

    def get_metadata_field()
        return @@column
    end

    def get_method()
        return @@method
    end
end

class Massage
    require 'thread'

    @@column_mappings = []
    @ba = nil

    def initialize()        
        @@column_mappings << ColumnMapping.new("ESI Folder Path", "get_esi_folder_path")
        @@column_mappings << ColumnMapping.new("Has Embedded Files", "get_has_embedded_items")
        @ba = $utilities.getBulkAnnotatercolumn_mappings
    end
end

When I debug, the data in @@column_mappings are two instances of the second line; @@column_mappings << ColumnMapping.new("Has Embedded Files", "get_has_embedded_items").

For some reason, it overwrites the array with the last inserted item, why?

Answer 1

For some reason, it overwrites the array with the last inserted item, why?

No, it doesn't. The items are separate/distinct. But the initializer for the second item mutates the "global" class variables, so all items look the same.

Don't use class variables (@@column), use instance variables (@column).

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