package com.test;

import java.io.BufferedInputStream;
import java.io.BufferedReader;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileReader;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.LineNumberReader;

import org.databene.contiperf.PerfTest;
import org.databene.contiperf.junit.ContiPerfRule;
import org.junit.Rule;
import org.junit.Test;

public class HugeFileLineCounter {

	public static final String hugeFilePath = "c:/test.log";

	@Rule
	public ContiPerfRule rule = new ContiPerfRule();

	// samples: 20
	// max: 1353
	// average: 1308.55
	// median: 1309
	@Test
	@PerfTest(invocations = 20, threads = 1)
	public void count1() throws IOException {
		LineNumberReader reader = new LineNumberReader(new FileReader(new File(
				hugeFilePath)));
		reader.skip(Long.MAX_VALUE);
		reader.close();
		System.out.println(reader.getLineNumber());
	}

	// most quickly sloution
	// samples: 20
	// max: 654
	// average: 507.6
	// median: 494
	@Test
	@PerfTest(invocations = 20, threads = 1)
	public void count2() throws IOException {
		InputStream is = new BufferedInputStream(new FileInputStream(
				hugeFilePath));
		int count = 0;
		try {
			byte[] c = new byte[1024];
			int readChars = 0;
			while ((readChars = is.read(c)) != -1) {
				for (int i = 0; i < readChars; ++i) {
					if (c[i] == '\n')
						++count;
				}
			}
		} finally {
			is.close();
		}
		System.out.println(count);
	}

	// samples: 20
	// max: 622
	// average: 504.8
	// median: 495
	@Test
	@PerfTest(invocations = 20, threads = 1)
	public void count3() throws IOException {
		InputStream is = new BufferedInputStream(new FileInputStream(
				hugeFilePath));
		int count = 0;
		try {
			byte[] c = new byte[2048];
			int readChars = 0;
			while ((readChars = is.read(c)) != -1) {
				for (int i = 0; i < readChars; ++i) {
					if (c[i] == '\n')
						++count;
				}
			}
		} finally {
			is.close();
		}
		System.out.println(count);
	}

	// samples: 20
	// max: 1138
	// average: 1050.75
	// median: 1047
	@Test
	@PerfTest(invocations = 20, threads = 1)
	public void count4() throws IOException {
		BufferedReader reader = new BufferedReader(new InputStreamReader(
				new FileInputStream(hugeFilePath), "UTF8"));
		int count = 0;
		try {
			char[] c = new char[1024];
			int readChars = 0;
			while ((readChars = reader.read(c)) != -1) {
				for (int i = 0; i < readChars; ++i) {
					if (c[i] == '\n')
						++count;
				}
			}
		} finally {
			reader.close();
		}
		System.out.println(count);
	}
}