code: function(roleName)
  	{
          var app = this;
  		var role = {permissions:[]};
  		try
  		{
              if(app.roles.hasOwnProperty(roleName)){
                  role = app.roles[roleName];
              }else{                
                  throw "not found";
              }
  		}
  		catch(e)
  		{
  			var objFilePath = path.join(app._path,"roles",roleName);
  			if(fs.existsSync(objFilePath+".js"))
  			{
  				var roleConfig = require(objFilePath);
                  if(typeof app.roles != "object") app.roles={};
  				app.roles[roleName]= roleConfig.permissions;                    
                  if(roleConfig.hasOwnProperty('isDefault') && roleConfig.isDefault == true){
                      app.defaultRoles.push(roleName);
                  }
                  role = roleConfig.permissions;
  			}
  		}
  		return role;
  	}
docs: Get specified openbiz pre-defined system role.
  
  This method it part of {@link openbiz.objects.Application},
  please never call this directly by ObjectService.
  
  if need to call this method, you have to use javascript's function.apply(applicationPointer,params)
  please see sample
  @memberof openbiz.services.ObjectService
  @param {string} roleName - The specified system role name
  @returns {array.<string>} Array of permission names,
  the permission could be used by {@link openbiz.policies.ensurePermission} middle-ware for protect resource access
  @example
  //below code is how to get the role named "cubi-admin"
  //cubiApp is instance of openbiz.objects.Application
  var cubiAdmin = app.getRole("cubi-admin");
  
  //cubiAdmin will looks like below
  // [
  //   "cubi-user-manage",
  //   "cubi-contact-manage",
  //   "cubi-account-manage"
  // ]
  @example
  //if you want to call this method directly , please try this way
  require('openbiz/services/ObjectService').getRole.apply(applicationPointer,roleName)