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Postsdbo
PO
 

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  1. PO
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    <p>If you want to store all lines in 2D array, you can use something like that:</p> <pre><code>public static void main(String[] args) throws Exception { FileInputStream inputStream = new FileInputStream("file.txt"); InputStreamReader streamReader =new InputStreamReader(inputStream,"UTF-8"); BufferedReader in = new BufferedReader(streamReader); int increment = 10; int size = 0; // number of lines String[][] all = new String[increment][]; for(String line; (line = in.readLine()) != null;) { String[] data = line.split(","); all[size++] = data; if(all.length == size) { // Increment capacity String[][] tmp = new String[all.length + increment][]; for(int i = 0; i &lt; data.length; i++) { tmp[i] = all[i]; } all = tmp; } } // Trim to size String[][] tmp = new String[size][]; for(int i = 0; i &lt; size; i++) { tmp[i] = all[i]; } all = tmp; </code></pre> <p>Sorting: If your teacher not say nothing about <code>java.util.Comparator</code>:</p> <pre><code> Arrays.sort(all, new Comparator&lt;String[]&gt;() { @Override public int compare(String[] a, String[] b) { // By year? int yearA = Integer.parseInt(a[0]); int yearB = Integer.parseInt(b[0]); return yearA - yearB; } }); </code></pre> <p>Although it may not be very useful sort, because the structure does not allow a quick search.</p> <p>Query: And finally the user input:</p> <pre><code> String input = null; Scanner sc = new Scanner(System.in); do { System.out.print("Input the year: "); String year = sc.nextLine(); for(int i = 0; i &lt; size; i++) { if (all[i][0].equals(year)) { // out data } } } while (input == null || input.isEmpty()); } </code></pre>
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    1. POHow to make an array from array of objects
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    1. USPaul Vargas
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    1. COthank you so much for your help, learnt a lot just reading that lol
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