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POjava- Read data from a file for further processing
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  1. POjava- Read data from a file for further processing
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    copied!<p>I'm new to java and I would like to ask you for help. I have some data stored in a txt file, each line holds three integers, separated by space. I would like to read the data from the file and then put this data in arrays for further processing, if certain conditions are met (in my case- third int is greater than 50). I read some questions about how to read the number of lines in a file or the file itself, but I can't seem to combine it all together to make it work. The latest version of the code looks like this:</p> <pre><code>public class readfile { private Scanner x; public void openFile(){ try{ x = new Scanner(new File("file.txt")); } catch (Exception e){ System.out.println("could not find file"); } } public void readFile() throws IOException{ LineNumberReader lnr = new LineNumberReader(new FileReader(new File("file.txt"))); int i = lnr.getLineNumber(); int[] table1 = new int[i]; int[] table2 = new int[i]; while(x.hasNextInt()){ int a = x.nextInt(); int b = x.nextInt(); int c = x.nextInt(); for (int j=0; j&lt; table1.length; j++) { if(c &gt; 50) { table1[j]=a; table2[j]=b; } } }System.out.printf(" %d %d", table1, table2); } public void closeFile(){ x.close(); } } </code></pre> <p>main is located in another file.</p> <pre><code>public static void main(String[] args) { readfile r = new readfile(); r.openFile(); try { r.readFile(); } catch (Exception IOException) {} //had to use this block or it wouldn't compile r.closeFile(); } </code></pre> <p>when I use %d on printf method i don't see anything, when I use %s I get some gibberish on the output like </p> <pre><code>[I@1c3cb1e1 [I@54c23942 </code></pre> <p>what should I do to make it work (ie. print pairs of a b when c is > 50)?</p> <p>Thanks in advance for any help, and sorry if this turns out to be some blatantly obvious problem, but I really ran out of ideas on how to improve this :)</p>
 

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