Amending a string value with Performance and Efficency in mind

[Bryan Murphss]

Hi,

A few thoughts about the following would be great,

I have a String that can vary in length from null to 500 characters in length,
When the String contains the name of a book, i need the name of the book to be replaced with %BOOKSTART%book:<nameOfBook>%BOOKEND%,
there can be multiple books in the String (i.e. "There is a book:where and another one here book:here" - will be replaced with "There is a %BOOKSTART%book:where%BOOKEND% and another one here %BOOKSTART%book:here%BOOKEND%"

Whats the best way to do this with performance and efficency in mind?

Thanks in Advance,

Bryan

[Jesper de Jong]

Welcome to the Ranch.

Class String has lots of useful methods to search for a substring inside a string and replace text. Those methods are reasonably efficient.

[fred rosenberger]

I wouldn't do this in java at all...this is the kind of project perl or awk excel at. Of course, that assumes you are reading this from a file.

[Paul Clapham]

Jesper de Jong wrote:Those methods are reasonably efficient.

And if your strings are only 500 characters long, it very likely isn't worth anybody's time to consider alternative methods. At the present it appears you may be guilty of Premature Optimization.

[Bryan Murphss]

Hi,

Thanks for the comments,
I Appreciate the advice,

The String value is coming from an external third party web service so it isn't read from a file or can be pre-factored,

i have the following method:

	private String formatValue(String value){
		StringBuilder builder = new StringBuilder();
		boolean continueCheck = true;
		while (continueCheck){
			int position = value.indexOf("book");
			if(position >-1){
				String start = value.substring(0, value.indexOf("book"));
				String bookString = value.substring(value.indexOf("book"));
				String book;
				if(book.indexOf(" ") > -1)
					book = bookString.substring(0, book.indexOf(" "));
				else
					book = bookString;
				builder.append(start);
				builder.append("%BOOKSTART%");
				builder.append(book);
				builder.append("%BOOKEND%");
				value = value.substring(start.length() + book.length());
			}
			else {
				continueCheck = false;
				builder.append(value);
			}
		}
		return builder.toString();
	}

do you think this is efficent enough or should there be a more better performance way?

Thanks,

Bryan

[Paul Clapham]

I think it's efficient enough, yes. Although I haven't looked at the code at all. My point is, what I think about the efficiency of your code is irrelevant. If it isn't efficient enough for you, then you should look at doing something about that. Nobody else's opinion matters.

[Bryan Murphss]

Your right.

Thanks for the advice