SequenceInputStream 合併流與切割流

將多個流合併成一個流

SequenceInputStream(Enumeration<? extends InputStream> e) 
SequenceInputStream(InputStream s1, InputStream s2) 

例：將多個文件合併到一個流中，再寫到一個文件中：

                Vector<FileInputStream> v = new Vector<FileInputStream>();

		v.add(new FileInputStream("c:\\1.txt"));
		v.add(new FileInputStream("c:\\2.txt"));
		v.add(new FileInputStream("c:\\3.txt"));

		Enumeration<FileInputStream> en = v.elements();

		SequenceInputStream sis = new SequenceInputStream(en);

		FileOutputStream fos = new FileOutputStream("c:\\4.txt");

		byte[] buf = new byte[1024];

		int len =0;
		while((len=sis.read(buf))!=-1)
		{
			fos.write(buf,0,len);
		}

		fos.close();
		sis.close();

合併文件

ArrayList<FileInputStream> aList = new ArrayList<FileInputStream>();// 爲什麼要用list,因爲Vector已經過時了。

		for (int x = 1; x <= 4; x++)
		{
			aList.add(new FileInputStream("d:\\tmp\\" + x + ".part"));// 循環的將d:\\tmp\\下的part文件加入aList中
		}

		final Iterator<FileInputStream> it = aList.iterator();

		Enumeration<FileInputStream> en = new Enumeration<FileInputStream>()
		{

			@Override
			public FileInputStream nextElement()
			{

				// TODO Auto-generated method stub
				return it.next();
			}

			@Override
			public boolean hasMoreElements()
			{

				// TODO Auto-generated method stub
				return it.hasNext();
			}
		};

		SequenceInputStream sis = new SequenceInputStream(en);
		FileOutputStream fos = new FileOutputStream("d:\\tmp\\aa.exe");
		byte[] buf = new byte[1024 * 1024];
		int len = 0;
		while ((len = sis.read(buf)) != -1)
		{
			fos.write(buf, 0, len);
		}
		fos.close();
		sis.close();

切割文件

		FileInputStream fis = new FileInputStream("d:\\tmp\\plsqldev.exe");
		FileOutputStream fos = null;
		byte[] bytes = new byte[1024 * 1024 * 3];
		int len = 0;
		int count = 1;
		while ((len = fis.read(bytes)) != -1)
		{

			fos = new FileOutputStream("d:\\tmp\\" + (count++) + ".part");
			fos.write(bytes, 0, len);
		}

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