Are you trying to open these to allow access from the internet, or are you trying to open them just for fun? If so, a simple Java loop can do that:
for(int i=6500; i<=7000; i++){
ServerSocket sSock;
try{
sSock=new ServerSocket(i);
catch (IOException e){
System.out.println(e);
}
}
}
sSock.close();