Log File Parser in Java: Explanation & Practice

Problem summary

Parse a log file and extract entries matching a severity level.

Starter code

import java.io.*;

public class Main {
    public static void main(String[] args) {
        String level = "ERROR"; // Test case 1
        
        // Filter log entries by level
        // Print matching entries
    }
}

Expected output and test cases

• Error entries

  2024-01-15 10:30:00 ERROR Database connection failed
  2024-01-15 10:35:00 ERROR Timeout occurred

• Warning entries

  2024-01-15 10:32:00 WARN Low memory

• No matches

Hints

1. Check if line contains level
2. Print matching lines only
3. Consider using indexOf or contains

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