example.js

(function() {
  var PackerMap=function(element,options){
  };
  
  PackerMap.prototype.center=function(lat,lng){
    
    
  }
  $.fn.packerMap = function(options,prop,prop2) {
    var args = Array.prototype.slice.call(arguments);
    return this.each(function() {
        var $this = $(this);
        var data = $this.data('packerMap');
        if (!data){
            $this.data('packerMap', (data = new PackerMap(this, options)));
        }
        if(typeof options  == 'string'){
          var argumentArray = args.slice(1);
          data[options].apply(data,argumentArray);
        }
    });
  } 
  $.fn.packerMap.Constructor =PackerMap;
  $.fn.packerMap.defaults={
    mapId:"map"

};
})();

use.js

$("#map").pacerMap(); //single map  
$("#map").packerMap("center",121,22);  //  move map center to  lat,lng:  121.22   # call PackerMap.center(121,22)

// 

$(".map").packerMap();  //  init multi google maps  if there are many  objects  with css class "map "