java - When to use string concat -

-

i have read quite few articles on +, stringbuilderappend , concat. but, if have 1 single concatenation best option?

  1. str1 + str2
  2. use string builder
  3. use string concat

i looking explanation when , 2 strings involved.

also when 2 strings involved complexity of string concat o(n) n length of longest string?

if you're doing single concatenation, use str1 + str2. easy read, , translated string concat compiler, fine if you're not going through loop or something. in fact, it's faster using stringbuilder if you're going concatenate strings single time.

see http://blog.codinghorror.com/the-sad-tragedy-of-micro-optimization-theater/ description of why shouldn't bother using string builder if you're not looping.

also when 2 strings involved complexity of string concat o(n) n length of longest string?

you that. i'd it's o(n) n combined length of 2 strings, since shortest string cannot, definition, order of magnitude larger longest string comes out same.


Comments

Post a Comment

Popular posts from this blog

javascript - How do I find how many occurences are there of a highlighted string, and which occurence is it? -

-
as title says, have website text inside div, there way highlight part of , know occurence is? if text has 4 occurences of word "something", , highlight 3rd, how information using javascript/jquery? http://jsfiddle.net/g09g35xa/6/ here's method seems work. highlight string want , when click button alert index of highlighted word in div. markup: <div id="thediv"> <p>the quick brown quick fox jumps on lazy dog</p> </div> <br /> <input id="findindex" type="button" value="find index of highlighted string" /> and js: function getselectedhtml() { try { if (window.activexobject) { var c = document.selection.createrange(); return c.htmltext; } return getselection().getrangeat(0).tostring(); } catch (e) { if (window.activexobject) { return document.selection.createrange(); } else { return ...
Read more

javascript - How to synchronize the Three.js and HTML/SVG coordinate systems (especially w.r.t. the y-axis)? -

-
i'm combining 3d content three.js html , svg content. three.js cssloader pretty job synchronizing placement of html , svg content in 3d world. but svg/html coordinate systems 'left-handed', whereas three.js coordinate system 'right-handed'. means y-axes reversed. in svg/html, y / top goes go down screen, , three.js uses more standard mathematical convention of y going down go down screen. i have continually convert 1 other, pretty error prone. know not first run (for example, look here ). has come general solution? here's tried: do in object3d .scale.y = -1 . may suspect, turns out disaster. turns inside-out, , don't try put camera in there. do in object3d .rotate.x = math.pi . more promising, z axis no longer consistent html concept of z-index. still, i'm using now. in html, don't use top , use bottom . in svg , inside <g transform="scale(1, -1)"> inside <g transform="translate(0, imageheight)"> . h...
Read more

java - Reading data from multiple zip files and combining them to one -

-
i want read data lets 4 zip files called zip1, zip2, zip3, zip4. of these zip files split 1 big zip file called "bigzip". want combine zip files 1 , compare bytes if 1 bigzip file matches size of bytes combined zip file of (zip1+zip2+zip3+zip4). getting small file size when combine size of 4 zip files. doing wrong? here code same: targetfilepath1, targetfilepath2, targetfilepath3, targetfilepath4 belongs path of 4 zip files. sourcefilepath path bigzip file class test { public static void main(string args[]) { zipoutputstream outstream = new zipoutputstream(new fileoutputstream(sourcebigzip)); readzip(sourcefilepath, targetfilepath1); readzip(sourcefilepath, targetfilepath2); readzip(sourcefilepath, targetfilepath3); readzip(sourcefilepath, targetfilepath4); outstream.close(); } static void readzip(string sourcebigzip, string targetfile) throws exception { zipinputstream instream = new zipinputstream(new file...
Read more