How to read last 5 lines of a .txt file into java

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长发绾君心
长发绾君心 2020-12-15 03:03

I have a text file that consists of several entries such as:

hello
there
my
name
is
JoeBloggs

How would I read the last five entries in des

9条回答
  •  被撕碎了的回忆
    2020-12-15 03:31

    Follow This Code To Improve Core Java Logic By Using Collectios.

    import java.io.FileNotFoundException;
        import java.io.FileReader;
        import java.util.ArrayList;
        import java.util.Collection;
        import java.util.Collections;
        import java.util.Scanner;
    
        public class REVERSE {
            public static void main(String[] args) {
                ArrayList al = new ArrayList();
                try {
                    Scanner sc = new Scanner(new FileReader("input.txt"));
                    while (sc.hasNextLine()) {
                        al.add(sc.nextLine());
                    }
                    System.out.println(al.get(0));
                    System.out.println(al.get(1));
                    System.out.println(al.get(2));
                    System.out.println(al.get(3));
                    System.out.println(al.get(4));
    
                    Collections.reverse(al);
                    /*
                     * for (String s : al) { System.out.println(s); }
                     */
                    System.out.println(al.get(0));
                    System.out.println(al.get(1));
                    System.out.println(al.get(2));
                    System.out.println(al.get(3));
                    System.out.println(al.get(4));
                    /*
                     * for (int i = 0; i < al.size(); i++) {
                     * System.out.println(al.get(i)); }
                     */
                } catch (FileNotFoundException e) {
    
                }
    
            }
        }
    

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