保存输入流

public class SaveStream {
    private InputStream input;
    private byte[] data = new byte[0];

    public SaveStream(InputStream input) throws IOException {
        this.input = input;
        save();
    }

    private void save() throws IOException {
        ByteArrayOutputStream output = new ByteArrayOutputStream();
        byte[] buffer = new byte[1024];
        int len = -1;
        while ((len = input.read(buffer)) != -1) {
            output.write(buffer, 0, len);
        }
        data = output.toByteArray();
    }

    public InputStream getInputStream() {
        return new ByteArrayInputStream(data);
    }
}