Sort File Lines in Java: Explanation & Practice

Problem summary

Read file lines, sort them alphabetically, and write to output.

Starter code

import java.io.*;
import java.util.*;

public class Main {
    public static void main(String[] args) {
        // Sort lines alphabetically
        // Print sorted lines
    }
}

Expected output and test cases

• Sorted alphabetically

  Apple
  Banana
  Cherry

• Single chars sorted

  A
  B
  C
  D
  E

• Single line

  Zebra

Hints

1. Collect all lines in List
2. Use Collections.sort()
3. Write sorted list to file

Related File I/O exercises

• Practice Merge Multiple Files in Java
• Practice Remove Duplicate Lines in Java
• Practice File Statistics in Java

Practice all File I/O exercises · Run this idea in the Java compiler