does anyone know how to convert String to primitive int without use of Wrapper classes.
Not sure I understand what you are asking. Do you want to do something like
without using the nice builtin parse functions?
The obvious way is to convert the String into a byte array, then iterate over the array. Pick up a byte, subtract "0" (ascii character zero) to get the value as an integer, then add it, and multiply by ten every time you pick up the next character.
Not sure this is really "advanced" so maybe I'm not understanding.
I shall make my question clear to you.. For example String s="12"; I want to know how this string can be converted to primitive int without using the methods of Wrapper Class ie Integer class methods should not be used to convert it to primitive. Thanks in advance..
Following program shows a logic to convert a string to int without using wrapper class. But this logic will work when input is only a positive number. For negative number input you can modify the logic.
[ August 21, 2007: Message edited by: prakash chandra ] [ August 24, 2007: Message edited by: prakash chandra ]
Not that I think it matters, but are you sure that it's faster?
No, I'm never sure without hard cold benchmarks. And even then, I'm not sure that the benchmarks are measuring what I think they are measuring.
But
is likely to be slower than
Its less flexible, but when you don't care about radix, it skips a routine call setup/return. Code doesn't get much faster than subtracting a constant.