src/org/nutz/lang/stream/StringOutputStream.java
@Override
    public void write(int b) throws IOException {
        if (null == baos)
            throw new IOException("Stream is closed");
        baos.write(b);
    }
@Override
    public void write(int b) throws IOException {
        if (null == baos)
            throw new IOException("Stream is closed");
        baos.write(b);
    }
完成本方法后,确认字符串已经完成写入后,务必调用flash方法!