Adding Property names on Property Transfer by groovy

Hi,

I am trying to add propety names to the property transfer step through groovy taking property names from a file . But failed.

Please help me on this. Below is the code...

// read the file
def properties = new java.util.Properties();
properties.load( new java.io.FileInputStream( "C:\\def.txt" ));
System.out.println("File was found........");
def targetStep = testRunner.testCase.getTestStepByName( "Property Transfer" );

//def names = properties.propertyNames();
def names = [];
names =  properties.propertyNames();

while( names.hasMoreElements() )
{
def name = names.nextElement();

targetStep.addProperty( name ) ;

}