Java 按行切割文件

最近公司项目需要把一个大文件按行分割为若干个小文件，对每一个小文件进行单独处理，以提高效率。

SplitFileTest.java

import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.io.InputStream;
import java.io.InputStreamReader;
import java.io.OutputStream;
import java.io.OutputStreamWriter;

/**
 * 按行分割文件 工具类
 * @author FX_SKY
 *
 */
public class SplitFileTest {

	/**
	 * @param args
	 */
	public static void main(String[] args) {
		test();
	}

	private static void test() {
		int startRowNumber = 0;
		int rowNumberSize = 60000;
		String dirPath = "D:/fbb/myWorkSpacev_GanJiC/FinalDB/";
		String sourceFileName = "201348-feng-v001ganjicom";
		
		for(int i=0;i<11;i++){
			startRowNumber = i*rowNumberSize;
			splitFile(startRowNumber,rowNumberSize,dirPath,sourceFileName);
		}
	}

	/**
	 * 从指定行数 startRowNumber起，截取 rowNumberSize 行保存到一个单独的文件，命名为 sourceFileName_1.后缀名
	 * @param startRowNumber
	 * @param rowNumberSize
	 * @param dirPath
	 * @param sourceFileName 
	 */
	public static void splitFile(int startRowNumber, int rowNumberSize,
			String dirPath, String sourceFileName) {
		
		File inputFile = new File(dirPath+sourceFileName);
		
		if(inputFile==null || !inputFile.exists()){
			throw new RuntimeException("待处理的数据文件不存在,文件路径:"+inputFile.getAbsolutePath());
		}
		
		System.out.println("开始分割文件  "+sourceFileName);
		
		String suffix = "";
		String realFileName = sourceFileName;
		int index = sourceFileName.lastIndexOf(".");
		
		if(index>0){
			//abc.txt
			suffix = sourceFileName.substring(index, sourceFileName.length());	//.txt
			realFileName = sourceFileName.substring(0, sourceFileName.lastIndexOf("."));	//abc
		}
		
		int serilizeNumber = 1;
		String outputPath = dirPath+realFileName+"_"+serilizeNumber + suffix;
		File outputFile = new File(outputPath);
		
		while(outputFile.exists()){	//判断分割后的文件是否已经存在
			
			serilizeNumber++;
			
			outputPath = dirPath+realFileName+"_"+serilizeNumber + suffix;
			outputFile = new File(outputPath);
		}
		
		System.out.println("分割后的文件 "+outputPath);
		
		int currentIndex = 0;	//当前的行数
		int writeNumber = 0;	//已经写出的行数
		
		InputStream in = null;
		InputStreamReader reader = null;
		BufferedReader br = null;
		
		OutputStream out = null;
		OutputStreamWriter writer = null;
		BufferedWriter bw = null;
		
		try {
			in = new FileInputStream(inputFile);
			reader = new InputStreamReader(in,"utf-8");//指定编码
			br = new BufferedReader(reader);

			//写出
			out = new FileOutputStream(outputFile);
			writer = new OutputStreamWriter(out, "utf-8");
			bw = new BufferedWriter(writer);
			
			String line = null;
			String newLine = null;

			
			while((line=br.readLine())!=null){
				
				currentIndex++;
				
				if(writeNumber>=rowNumberSize){
					break;
				}
				
				if(currentIndex>=startRowNumber){
					newLine = line;
					
					bw.write(newLine);
					bw.newLine();
					
					writeNumber++;
				}
			}
			
			bw.flush();
			
			System.out.println("分割文件完成...");
			
		}catch (Exception e) {
			e.printStackTrace();
		}finally{
			try {
				br.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
			try {
				bw.close();
			} catch (IOException e) {
				e.printStackTrace();
			}
		}
	}
}

OK，搞定啦，时间比较仓促，程序有不完善的地方还请大家赐教，呼呼...