reading dates from file - how to format

Hello again,
I cannot understand how to format dates in interpreted Java. I have the following in my script:-

File inputFile = new File( "Datefile.txt" );

import java.text.SimpleDateFormat;
FileReader in = new FileReader( inputFile );
BufferedReader buffRead = new BufferedReader( in );

while( ( searchTerm = buffRead.readLine() )!=null)
{

SimpleDateFormat formatter = new SimpleDateFormat( "dd/MM/yyyy" );
String formattedDate = formatter.format( searchTerm );
session.setVariable( "ActDate", formattedDate );
session.log( session.getVariable( "ActDate" ) );

}

in.close();
buffRead.close();

Any help appreciated as Im not a coder of Java....

thanks, Kerri