在 Java 中解析 A​​pache 访问日志

// Java program to count the no. of IP address
// count for successful http response 200 code.
import java.io.*;
import java.util.*;
import java.util.regex.Matcher;
import java.util.regex.Pattern;
 
class FindSuccessIpCount {
 
	public static void findSuccessIpCount(String record)
	{
		// Creating a regular expression for the records
		final String regex = "^(\\S+) (\\S+) (\\S+) " +
			"\\[([\\w:/]+\\s[+\\-]\\d{4})\\] \"(\\S+)" +
			" (\\S+)\\s*(\\S+)?\\s*\" (\\d{3}) (\\S+)";
 
		final Pattern pattern = Pattern.compile(regex, Pattern.MULTILINE);
		final Matcher matcher = pattern.matcher(record);
 
		// Creating a Hashmap containing string as
		// the key and integer as the value.
		HashMap countIP = new HashMap();
		while (matcher.find()) {
 
			String IP = matcher.group(1);
			String Response = matcher.group(8);
			int response = Integer.parseInt(Response);
 
			// Inserting the IP addresses in the
			// HashMap and maintaining the frequency
			// for each HTTP 200 code.
			if (response == 200) {
				if (countIP.containsKey(IP)) {
					countIP.put(IP, countIP.get(IP) + 1);
				}
				else {
					countIP.put(IP, 1);
				}
			}
		}
 
		// Printing the hashmap
		for (Map.Entry entry : countIP.entrySet()) {
			System.out.println(entry.getKey() + " " + entry.getValue());
		}
	}
	public static void main(String[] args)
	{
		final String log = "123.123.123.123 - - [26/Apr/2000:00:23:48 -0400] \"GET /pics/wpaper.gif HTTP/1.0\" 200 6248 \"http:// www.jafsoft.com/asctortf/\" \"Mozilla/4.05 (Macintosh; I; PPC)\"\n"
						+ "123.123.123.123 - - [26/Apr/2000:00:23:47 -0400] \"GET /asctortf/ HTTP/1.0\" 200 8130 \"http:// search.netscape.com/Computers/Data_Formats/Document/Text/RTF\" \"Mozilla/4.05 (Macintosh; I; PPC)\"\n"
						+ "123.123.123.124 - - [26/Apr/2000:00:23:48 -0400] \"GET /pics/5star2000.gif HTTP/1.0\" 200 4005 \"http:// www.jafsoft.com/asctortf/\" \"Mozilla/4.05 (Macintosh; I; PPC)\"\n"
						+ "123.123.123.123 - - [26/Apr/2000:00:23:50 -0400] \"GET /pics/5star.gif HTTP/1.0\" 404 1031 \"http:// www.jafsoft.com/asctortf/\" \"Mozilla/4.05 (Macintosh; I; PPC)\"\n"
						+ "123.123.123.126 - - [26/Apr/2000:00:23:51 -0400] \"GET /pics/a2hlogo.jpg HTTP/1.0\" 200 4282 \"http:// www.jafsoft.com/asctortf/\" \"Mozilla/4.05 (Macintosh; I; PPC)\"\n"
						+ "123.123.123.123 - - [26/Apr/2000:00:23:51 -0400] \"GET /cgi-bin/newcount?jafsof3&width=4&font=digital&noshow HTTP/1.0\" 200 36 \"http:// www.jafsoft.com/asctortf/\" \"Mozilla/4.05 (Macintosh; I; PPC)\"\n";
 
		findSuccessIpCount(log);
	}
}

输出：