import java.io.BufferedReader;
import java.io.BufferedWriter;
import java.io.File;
import java.io.FileInputStream;
import java.io.FileNotFoundException;
import java.io.FileOutputStream;
import java.io.FileReader;
import java.io.FileWriter;
import java.util.ArrayList;
import java.util.List;

public class Test1
{

    static File file = new File("D:\\11");

    static List<File> lists = new ArrayList<File>();// 存储所有.txt文件的绝对路径

    /**
     * 将所有文件合并到同一个文件当中
     * 
     * @throws Exception
     */
    public static void uniteFile() throws Exception
    {
        File newFile = new File("D:\\11\\final.txt");

        FileReader fr;

        FileWriter fw = new FileWriter(newFile, true);
        ;

        BufferedReader bufr = null;

        BufferedWriter bufw = new BufferedWriter(fw);

        for (File file : lists)
        {
            fr = new FileReader(file);

            bufr = new BufferedReader(fr);

            String len = bufr.readLine();

            while (null != len)
            {
                bufw.write(len);

                bufw.flush();

                len = bufr.readLine();
            }

        }
        bufw.close();
        bufr.close();
    }

    /**
     * 将文件按照1KB分割
     * 
     * @param f
     * @throws Exception
     */
    public static void divideFile() throws Exception
    {
        FileInputStream fis = new FileInputStream("D:\\11\\final.txt");

        FileOutputStream fos = null;

        byte[] b = new byte[1024];

        for (int i = 1;; i++)
        {
            if (fis.read(b) == -1)
            {
                break;
            }
            int length = fis.read(b);

            File smallfile = new File("D:\\11\\22\\33\\" + i + ".txt");

            fos = new FileOutputStream(smallfile);

            fos.write(b);
            System.out.println("写入文件" + i + "成功！");

        }
        fos.close();
        fis.close();
    }

    public static void seekTxt(File f)
    {
        File[] files = f.listFiles();

        for (File file : files)
        {
            if (file.isDirectory())
            {
                seekTxt(file);
            }
            else
            {
                if (file.getName().split("\\.")[1].equals("txt"))
                {
                    lists.add(file);
                }
            }
        }

    }

    public static void main(String[] args) throws Exception
    {
        seekTxt(file);

        uniteFile();

        divideFile();

    }

}