Solved

Small memory related question

Posted on 2004-09-10
2
237 Views
Last Modified: 2010-03-31
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

0
Comment
Question by:oroussea
[X]
Welcome to Experts Exchange

Add your voice to the tech community where 5M+ people just like you are talking about what matters.

  • Help others & share knowledge
  • Earn cash & points
  • Learn & ask questions
  • 2
2 Comments
 
LVL 86

Accepted Solution

by:
CEHJ earned 125 total points
ID: 12028502
1. Probably not. Since these concatenations are done by StringBuffer internally, they will probably get appended as characters to the StringBuffer
2. No 'memory' as such is allocated (although of course memory is allocated for the StringBuffer) as an append happens (see 1.)
3. It's a good idea, as it makes the code more readable, although it won't affect the code footprint as far as memory/execution time is concerned. The Java convention is to capitalize constants.
4. Yes
0
 
LVL 86

Expert Comment

by:CEHJ
ID: 12028996
8-)
0

Featured Post

PeopleSoft Has Never Been Easier

PeopleSoft Adoption Made Smooth & Simple!

On-The-Job Training Is made Intuitive & Easy With WalkMe's On-Screen Guidance Tool.  Claim Your Free WalkMe Account Now

Question has a verified solution.

If you are experiencing a similar issue, please ask a related question

Suggested Solutions

Title # Comments Views Activity
How to get all the API from website? 11 160
collection output issue 9 91
passing enum to a method 4 49
Selenium findElement(By.classname  identifier 15 32
An old method to applying the Singleton pattern in your Java code is to check if a static instance, defined in the same class that needs to be instantiated once and only once, is null and then create a new instance; otherwise, the pre-existing insta…
Java contains several comparison operators (e.g., <, <=, >, >=, ==, !=) that allow you to compare primitive values. However, these operators cannot be used to compare the contents of objects. Interface Comparable is used to allow objects of a cl…
Viewers learn about the third conditional statement “else if” and use it in an example program. Then additional information about conditional statements is provided, covering the topic thoroughly. Viewers learn about the third conditional statement …
Viewers will learn about arithmetic and Boolean expressions in Java and the logical operators used to create Boolean expressions. We will cover the symbols used for arithmetic expressions and define each logical operator and how to use them in Boole…
Suggested Courses

734 members asked questions and received personalized solutions in the past 7 days.

Join the community of 500,000 technology professionals and ask your questions.

Join & Ask a Question