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POReading in large text files, problems with the garbage collector and Scanner object
 

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    <p>I am writing a program that needs to read in very large files (about 150Mb of text). I am running into an out of memory error when I try to read in files that are larger than 50Mb. Here is an excerpt from my code.</p> <pre><code>if (returnVal == JFileChooser.APPROVE_OPTION) { file = fc.getSelectedFile(); gui.setTitle("Fluent Helper - " + file.toString()); try{ scanner = new Scanner(new FileInputStream(file)); gui.getStatusLabel().setText("Reading Faces..."); while(scanner.hasNext()){ count++; if(count&lt;1000000){ System.gc(); count = 0; } readStr = scanner.nextLine()+ "\n"; if(readStr.equals("#\n")){ isFaces = false; gui.getStatusLabel().setText("Reading Cells..."); }else if(isFaces){ faces.add(new Face(readStr)); }else{ cells.add(new Cell(readStr)); } } }catch (Exception e){ e.printStackTrace(); }finally{ try{ scanner.close(); }catch(Exception e){ e.printStackTrace(); } } System.out.println("flie selected"); } else { System.out.println("file not selected"); } </code></pre> <p>the small block that calls the garbage collector every arbitrary number of reads is something I added to solve the memory problem, but it doesn't work. Instead the program hangs and never gets to the cells portion of the file (which should happen in less than a second). Here is the block.</p> <pre><code> if(count&lt;1000000){ System.gc(); count = 0; } </code></pre> <p>My guess is that maybe the Scanner's pointer is getting garbage collected or something. I really don't have any clue. Launching the program with a larger heap is not really an option for me. The program should be usable by people with out very much computer knowledge.</p> <p>I would like a solution to get the file in with out a problem, be it a memory management one or fixing the scanner or a more efficient means of reading the file. Thanks everyone.</p>
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