JAVA 文本高效行数统计

测试程序:
    网上有说使用正则表达式,若文件较大的话效率不是很高!

import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.IOException;
import java.io.InputStreamReader;
import java.io.LineNumberReader;

public class TestIO {

	public static void main(String[] args) {
		getLineNumber("c:\\test.txt");
	}

	// 统计行数
	private static int getLineNumber(String fileName) {
		long start = System.currentTimeMillis();
		int lineNum = 0;
		char[] buf = new char[8192];
		LineNumberReader lnr = null;

		try {
			lnr = new LineNumberReader(new InputStreamReader(
					new FileInputStream(fileName)));

			while (lnr.read(buf) != -1) {
				;
			}

			lineNum = lnr.getLineNumber() + 1;
		} catch (FileNotFoundException e) {
			e.printStackTrace();
		} catch (IOException e) {
			e.printStackTrace();
		} finally {
			try {
				if (null != lnr) {
					lnr.close();
				}
			} catch (IOException ex) {
				ex.printStackTrace();
			}
		}

		long end = System.currentTimeMillis();

		System.out.println("Use Time: " + (end - start) + " Line Num: "
				+ lineNum);

		return lineNum;
	}

}
     

执行结果:
Use Time: 109ms Line Num: 2400000