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  1. PO
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    <p>It is highly unlikely that any realistic use of split would "consume lots of memory". Your input would have to be huge (many, many megabytes) and your result split into <em>many millions</em> of parts for it to even be noticed.</p> <p>Here's some code that creates a random string of approximately 1.8 million characters and splits it into over 1 million Strings and outputs the memory used and time taken.</p> <p>As you can see, it ain't much: 61Mb consumed in just 350ms.</p> <pre><code>public static void main(String[] args) throws Exception { StringBuilder sb = new StringBuilder(); for (int i = 0; i &lt; 99999; i++) { sb.append(Math.random()); } long begin = System.currentTimeMillis(); String string = sb.toString(); sb = null; System.gc(); long startFreeMem = Runtime.getRuntime().freeMemory(); String[] strings = string.split("(?=[0-5])"); long endFreeMem = Runtime.getRuntime().freeMemory(); long execution = System.currentTimeMillis() - begin; System.out.println("input length = " + string.length() + "\nnumber of strings after split = " + strings.length + "\nmemory consumed due to split = " + (startFreeMem - endFreeMem) + "\nexecution time = " + execution + "ms"); } </code></pre> <p>Output (run on fairly typical windows box):</p> <pre><code>input length = 1827035 number of strings after split = 1072788 memory consumed due to split = 71740240 execution time = 351ms </code></pre> <p>Interestingly, <em>without</em> <code>System.gc()</code> the memory used was about 1/3:</p> <pre><code>memory consumed due to split = 29582328 </code></pre>
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    1. POMemory issues with String.split()
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    1. USBohemian
    1. USBohemian
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      1. VTUpMod
    1. COI would use `-XX:-UseTLAB` for more accurate memory usage and move the `sb.toString()` to before your `start` Splitting on 60% of characters is a little crazy. How about `[0-1]`?
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      1. USPeter Lawrey
    2. COPet hate: Don't use StringBuffer is you can use StringBuilder. ;)
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      1. USPeter Lawrey
    3. CO@PeterLawrey Crap! I meant to use `StringBuilder`. And I moved the `toString()`. Bit less memory used by `split()`. Splitting on so much because I wanted to create a crazy number of String objects to prove `split()` is not the villain.
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