SequenceInputStream merges and cuts streams

Combine multiple streams into one stream

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

Example: Combine multiple files into one stream and write to one file:

                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();

Merge files

ArrayList<FileInputStream> aList = new ArrayList<FileInputStream>();// Why use list, because Vector is outdated.
		
		for (int x = 1; x <= 4; x++)
		{
			aList.add(new FileInputStream("d:\\tmp\\" + x + ".part"));// Add the part files under d:\\tmp\\ to aList cyclically
		}
		
		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();

cut file

		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();