Java: OutputStream and InputStream

I have a class CBZip2OutputStream from "apache bzi2 libr开发者_Python百科ary" , it can transform binary data stream to bzi2 data stream. But I need to archive a string. Therefore, i think, i should create an input stream from that outputstream, write that data to outputstream and read archived data from inputstream... but how to link outputstream and inputstream?

You can just read from input stream and write to output stream. It is a common practice. IOUtils.copy() (from jakarta commons) does it, so you event do not need to implement the loop.

Alternatively you can use PipedInputStream and PipedOutputStream.

First, you probably want a DataOutputStream: it is designed to take primitives and objects and convert them to bytes. It does handle strings as well.

Next, use piped I/O: PipedInputStream and PipedOutputStream. You can use them to link streams together, similar to piping input from one process into another from the command line.

You can use several method to get an InputStream out of an OutputStream.

• write the data the data into a memory buffer (ByteArrayOutputStream) get the byteArray and read it again with a ByteArrayInputStream. This is the best approach if you're sure your data fits into memory.
• copy your data to a temporary file and read it back.
• use pipes: this is the best approach both for memory usage and speed (you can take full advantage of the multi-core processors) and also the standard solution offered by Oracle.
• use "circular buffers" or pipes trough an external library.

Here is a complete tutorial.