FTPClientでのログ取得方法

    FTPClient client = new FTPClient() {
        public OutputStream getOutputStream() {
            return new VerboseOutputStream( super.getOutputStream() );
        }
    };

    static class VerboseOutputStream extends FilterOutputStream {
        ByteArrayOutputStream log;
        public VerboseOutputStream( OutputStream _out ) {
            super( _out );
            log = new ByteArrayOutputStream();
        }
        public void write( byte[] _b, int _off, int _len ) throws IOException {
            out.write( _b, _off, _len );
            log.write( _b, _off, _len );
        }
        public void write( byte[] _b ) throws IOException {
            out.write( _b );
            log.write( _b );
        }
        public void write( int _b ) throws IOException {
            out.write( _b );
            log.write( _b );
        }
        public void flush() throws IOException {
            out.flush();
            System.out.println( new String( this.log.toByteArray() ) ); // ここを適宜変更
            log.reset();
        }
    }