TeeOutputStream does not call branch.close() when main.close() throws an exception

TeeOutputStream.close() looks like this:

    /**
     * Closes both streams. 
     * @throws IOException if an I/O error occurs
     */
    @Override
    public void close() throws IOException {
        super.close();
        this.branch.close();
    }

It is obvious that this.branch.close() is not executed when super.close() raises an exception. super.close() may in fact raise an IOException since ProxyOutputStream.handleIOException(IOException) is not overridden.