import java.io.BufferedReader;

import java.io.FileReader;

import java.io.IOException;

import java.util.ArrayList;

import java.util.HashMap;

import java.util.List;

import java.util.Map;

public class LogAnomalyDetector {

private static final int ANOMALY_THRESHOLD = 3; // Define anomaly threshold

private static final String LOG_FILE_PATH = "logfile.txt"; //Default logfile path

public static void main(String[] args) {

if (args.length > 0) {

LOG_FILE_PATH = args[0]; //Use argument if provided

}

try {

List<String> logEntries = readLogFile(LOG_FILE_PATH);

detectAndFlagAnomalies(logEntries);

} catch (IOException e) {

System.err.println("Error reading log file: " + e.getMessage());

}

}

/**

* Reads log entries from a file.

* @return A list of log entries.

* @throws IOException If an error occurs while reading the file.

*/

public static List<String> readLogFile(String filePath) throws IOException {

List<String> logEntries = new ArrayList<>();

try (BufferedReader reader = new BufferedReader(new FileReader(filePath))) {

String line;

while ((line = reader.readLine()) != null) {

logEntries.add(line);

}

}

return logEntries;

}

/**

* Detects and flags anomalies in the log entries.

* @param logEntries A list of log entries.

*/

public static void detectAndFlagAnomalies(List<String> logEntries) {

Map<String, Integer> wordCounts = new HashMap<>();

// Count word occurrences in each log entry

for (String entry : logEntries) {

String[] words = entry.toLowerCase().split("\\s+"); // Split into words, convert to lowercase

for (String word : words) {

wordCounts.put(word, wordCounts.getOrDefault(word, 0) + 1);

}

}

// Identify anomalies based on word frequency

for (String entry : logEntries) {

int anomalyCount = 0;

String[] words = entry.toLowerCase().split("\\s+");

for (String word : words) {

if (wordCounts.getOrDefault(word, 0) > ANOMALY_THRESHOLD) {

anomalyCount++;

}

}

if (anomalyCount > 0) {

System.out.println("Anomaly detected: " + entry);

}

}

}

}