behavior singleton model

exampleBehavior.js

(function(){

var SocketConnection = function() {
  this.connection = instanceConnection();
};

// This is a globally shared connection.
var singletonConnection = null;

window.SocketConnectionBehavior = {
  properties: {
    connection: {
      type: Object,
      value: function() {
        return getConnection();
      }
    }
  },
  // This function returns the global connection and creates an instance of it if necessary.
  getConnection: function() {
    if (singletonConnection === null) {
      singletonConnection = new SocketConnection();
    }
    return singletonConnection;
  }
});