public class StreamTest {

    public static void main(String[] args) {

        //准备一个文件文件内容是LOL，用来 字节输入流读取文件

        File file1 = new File("D:\\lolfilder\\lol.exe\\lol.txt");

        //准备一个空文件，用来字节输出流写入文件

        File file2 = new File("D:\\lolfilder\\lol.exe\\lol1.txt");

        try {

            FileInputStream fis = new FileInputStream(file1);

            FileOutputStream fos = new FileOutputStream(file2);

            byte[] all = new byte[(int) file1.length()];

            byte[] all2 = {65,97};

            fis.read(all);

            fos.write(all2);

            for(byte temp:all) {

                System.out.println(temp);

            }

            fis.close();

            fos.close();

        } catch (Exception e) {

            e.printStackTrace();

        }

    }

public class FileSplitTest {

    private static final int SPLIT_SIZE=100;

    public static void main(String[] args) {

         File file = new File("D:\\lolfilder\\lol.exe\\filesplitdemo.txt");

         splitFile(file, SPLIT_SIZE);

    }

    public static void splitFile(File file,int size) {

        try/*(FileInputStream fis = new FileInputStream(file);)

        可以将流定义在try中，当try，catch或finally结束后会自动关闭流，这是jdk7之后的技术

        */ {

            FileInputStream fis = new FileInputStream(file);

            byte []fisb = new byte[size];

            //fis.read(fisb);

            for(int i=1;fis.read(fisb, 0, size)>0;i++) {

                File subFile = new File(file.getAbsolutePath().replace(".txt",  "_" + i + ".txt"));

                FileOutputStream fos = new FileOutputStream(subFile);

                fos.write(fisb);

                fos.close();

            }

            fis.close();

        } catch (Exception e) {

            // TODO Auto-generated catch block

            e.printStackTrace();

        }

    }

public static void main(String[] args) {

         int i = 1;

         //建立输入文件

         File outFile = new File("D:\\lolfilder\\lol.exe\\mergedfile.txt");

         try {

             //建立输出流

         FileOutputStream fos = new FileOutputStream(outFile);

         //通过i依次读取

         while(new File("D:\\lolfilder\\lol.exe\\filesplitdemo_"+i+".txt").exists()) {

                File f = new File("D:\\lolfilder\\lol.exe\\filesplitdemo_"+i+".txt");

                FileInputStream fis = new FileInputStream(f);

                byte[] temp = new byte[fis.available()];

                fis.read(temp);

                fos.write(temp);

                i++;

                fis.close();

            }

         fos.close();

         }catch (Exception e) {

                // TODO Auto-generated catch block

                e.printStackTrace();

            }

         }