Small memory related question

Dear Java experts

I was wondering... in my code... to display a variable to the console i use the following like 1000+ times:

System.out.println("" + varName);

and

System.out.println("" + varName + " " + varName2);



My questions are related to the "" and " ".

1. In the examples above... does Java consider "" and " " as Strings? i mean... does it allocate (forgive my C example here) sizeof(String) + (numberOfCharsInString * 2 bytes per chars)?

2. Since there are more than 1000 of each in the code... does Java allocate memory for only one " " and ""? or does Java allocate 1000+ " " and ""?

3. Should i do this instead:

private final static String strEmptyString = "";
private final static String strSingleSpace = " ";

System.out.println(strEmptyString  + varName + strSingleSpace  + varName2);

4. Out of curiosity... in Java... can we do: "This is a String".length( );


So thanks in advance to everyone who will take time to clarify this!!

   -Mike