博客

原文地址：http://www.blogjava.net/landon/archive/2010/12/20/341197.html

把一个大文件切割成多个小文件

package chow.nio;

import java.io.FileInputStream;
import java.io.FileOutputStream;
import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.FileChannel;

public class ReadLargeTextNio {
	/**
	 * 
	 * 用NIO读取大文本（1G以上）
	 * 
	 */
	public static void main(String... args) throws IOException {
		FileInputStream fin = new FileInputStream("C:/xmlDir2/20m.xml");
		FileChannel fcin = fin.getChannel();

		ByteBuffer buffer = ByteBuffer.allocate(1024 * 1024 * 1); //1M

		int count = 1;
		while (true) {
			buffer.clear();
			int flag = fcin.read(buffer);
			if (flag == -1) {
				break;
			}
			buffer.flip();
			FileOutputStream fout = new FileOutputStream("c:\\xmlDir2\\" + count
					+ ".xml");
			FileChannel fcout = fout.getChannel();
			fcout.write(buffer);
			System.out.println("create file " + count);
			count++;
		}
	}
}