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POBufferedReader seems to only read last line of file
 

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  1. POBufferedReader seems to only read last line of file
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    <p>I'm trying to write a method to take a multiline tab-delimited file and return the contents of that file as an arraylist of String arrays (each line is a String[], and each such String[] is an element of an arraylist). My problem is, I can't tell if the output is correct or not. I've printed each arraylist element and String[] element as they are saved to the arraylist, and those printings look correct. But after the arraylist is returned and I print the String[] in it, they appear to only have the contents of the very last line of the file. I'm suspecting it might be something about FileReader or BufferedReader that I don't know. Anyhoo, here's the code:</p> <pre><code>public class DataParsingTest { static File AAPLDailyFile = new File("./textFilesForMethodTests/dataParsingPractice2.tsv"); public static void main(String[] args) throws FileNotFoundException, IOException { ArrayList&lt;String[]&gt; stringArrayList = fileToStringArray(AAPLDailyFile); System.out.println("stringArray.size() = " + stringArrayList.size()); System.out.println(stringArrayList.get(0)[0]); for (int i = 0; i &lt; stringArrayList.size(); i++) { for (int j = 0; j &lt; stringArrayList.get(i).length; j++) { System.out.println("index of arraylist is " + i + " and element at index " + j + " of that array is " + stringArrayList.get(i)[j]); } } } public static ArrayList&lt;String[]&gt; fileToStringArray(File file) throws FileNotFoundException, IOException { ArrayList&lt;String[]&gt; arrayListOfStringArrays = new ArrayList&lt;String[]&gt;(); FileReader fileReader = new FileReader(file); BufferedReader bufferedReader = new BufferedReader(fileReader); int nextChar = 0; int noOfTokens = 1; // because the first token doesn't have a tab or newline before it int startIndex = 0, endIndex = 0, tokenIndex = 0; String toRead = ""; toRead = bufferedReader.readLine(); for (int i = 0; i &lt; toRead.length(); i++) { if (toRead.charAt(i) == '\t') { noOfTokens++; } } System.out.println("noOfTokens = " + noOfTokens); bufferedReader.close(); fileReader.close(); String[] productString = new String[noOfTokens]; startIndex = 0; endIndex = 0; tokenIndex = 0; FileReader fileReader2 = new FileReader(file); BufferedReader bufferedReader2 = new BufferedReader(fileReader2); tokenIndex = 0; int count = 1; while ((toRead = bufferedReader2.readLine()) != null) { System.out.println("toRead = " + toRead); startIndex = -1; // [L - so that the first time an array element is assigned, it's upped to 0] endIndex = 0; tokenIndex = 0; while (true) { endIndex = toRead.indexOf("\t", startIndex + 1); if (endIndex == -1) { productString[tokenIndex] = toRead.substring(startIndex + 1); System.out.println("tokenIndex = " + tokenIndex); System.out.println("productString[" + tokenIndex + "] = " + productString[tokenIndex]); tokenIndex++; count++; arrayListOfStringArrays.add(productString); System.out.println("just added an array to the list. the first element is " + productString[0]); break; } productString[tokenIndex] = toRead.substring(startIndex + 1, endIndex); System.out.println("tokenIndex = " + tokenIndex); System.out.println("productString[" + tokenIndex + "] = " + productString[tokenIndex]); startIndex = endIndex; tokenIndex++; count++; } } fileReader2.close(); bufferedReader2.close(); return arrayListOfStringArrays; } } </code></pre> <p>The input file is:</p> <pre><code>1 2 3 4 5 6 </code></pre> <p>The output is:</p> <pre><code>noOfTokens = 2 toRead = 1 2 tokenIndex = 0 productString[0] = 1 tokenIndex = 1 productString[1] = 2 just added an array to the list. the first element is 1 toRead = 3 4 tokenIndex = 0 productString[0] = 3 tokenIndex = 1 productString[1] = 4 just added an array to the list. the first element is 3 toRead = 5 6 tokenIndex = 0 productString[0] = 5 tokenIndex = 1 productString[1] = 6 just added an array to the list. the first element is 5 stringArray.size() = 3 5 // from here on up, it looks like the method works correctly index of arraylist is 0 and element at index 0 of that array is 5 index of arraylist is 0 and element at index 1 of that array is 6 index of arraylist is 1 and element at index 0 of that array is 5 index of arraylist is 1 and element at index 1 of that array is 6 index of arraylist is 2 and element at index 0 of that array is 5 index of arraylist is 2 and element at index 1 of that array is 6 //these 6 lines only reflect the last line of the input file. </code></pre> <p>Thanks a mil!</p>
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