关于URL.openStream()长度限制问题

我在使用URL.openStream()的时候后台报错，但没看出来报什么错，URL的内容是https://XXX.XXX.XX.XXX/MMCPInterface_mt/CPInterface_mt.aspx?cpid=XXXon&mid=XXX&mobile=XXXXXXXX&port=&ywid=1002&msg=%E9%AB%98%E5%B1%B1%E5%B9%B3%E5%8E%9F%E5%8F%88%E5%90%8D%E4%B9%9D%E6%B9%96%E5%9D%AA%EF%BC%8C%E4%BD%8D%E4%BA%8E%E5%B7%9D%E9%84%82%E4%BA%A4%E7%95%8C%E5%A4%84%E3%80%82%E9%9D%A2%E7%A7%AF3%E4%B8%87%E5%A4%9A%E4%BA%A9%EF%BC%8C%E6%B5%B7%E6%8B%941700%E7%B1%B3%EF%BC%8C%E5%8D%97%E5%8C%97%E9%95%BF%E7%BA%A615%E5%85%AC%E9%87%8C%EF%BC%8C%E4%B8%9C%E8%A5%BF%E5%AE%BD%E7%BA%A63%E5%85%AC%E9%87%8C%EF%BC%8C%E8%A2%AB%E7%A7%B0%E4%B8%BA%E2%80%9C%E7%A5%9E%E5%86%9C%E6%B1%9F%E5%8D%97%E2%80%9D%E3%80%82%E4%B9%9D%E6%B9%96%E5%9D%AA%E5%9B%9B%E5%91%A8%E9%AB%98%E5%B1%B1%E7%8E%AF%E7%BB%95%EF%BC%8C%E6%9C%80%E9%AB%98%E5%B3%B02800%E7%B1%B3%EF%BC%8C%E5%BD%A2%E6%88%90%E4%B8%80%E9%81%93%E5%A4%A9%E7%84%B6%E5%B1%8F%E9%9A%9C%E3%80%82%E5%9C%A8%E4%B8%9C%E8%A5%BF%E6%9C%89%E4%B9%9D%E4%B8%AA%E5%A4%A7%E5%B1%B1%E6%A2%81%EF%BC%8C%E6%A2%81%E4%B8%8A%E6%A3%AE%E6%9E%97%E5%AF%86%E5%B8%83%EF%BC%8C%E6%B0%94%E5%8A%BF%E9%9B%84%E4%BC%9F%E3%80%82%E5%B1%B1%E6%A2%81%E9%97%B4%E4%B9%9D%E6%9D%A1%E5%B0%8F%E6%BA%AA%E7%8A%B9%E5%A6%82%E4%B9%9D%E6%9D%A1%E7%8E%89%E5%B8%A6%E4%BB%8E%E4%BA%91%E9%9B%BE%E4%B8%AD%E9%A3%98%E8%88%9E%E4%B8%8B%E6%9D%A5%E3%80%82%E5%9C%A8%E8%BF%99%E9%AB%98%E5%B1%B1%E5%B9%B3%E5%8E%9F%E4%B8%8A%E4%B9%9F%E6%81%B0%E5%A5%BD%E6%9C%89%E4%B9%9D%E4%B8%AA%E6%B9%96%E6%B3%8A%E9%B3%9E%E5%85%89%E9%97%AA%E9%97%AA%E3%80%82%E4%B8%80%E5%B1%B1%E4%B9%8B%E9%9A%94%E7%9A%84%E5%B0%8F%E4%B9%9D%E6%B9%96%E9%9D%A2%E7%A7%AF%E4%B8%BA5000%E4%BA%A9%EF%BC%8C%E4%B8%80%E6%9D%A1%E5%B0%8F%E6%BA%AA%E8%BF%9E%E4%B8%B2%E7%9D%80%E4%B9%9D%E4%B8%AA%E5%B0%8F%E6%B9%96%E6%B3%8A%E3%80%82%E5%A4%A7%E4%B9%9D%E6%B9%96%EF%BC%8C%E5%B0%8F%E4%B9%9D%E6%B9%96%E7%94%B1%E6%AD%A4%E8%80%8C%E5%BE%97%E5%90%8D%E3%80%82%E5%A4%A7%E4%B9%9D%E6%B9%96%E8%A5%BF%E9%80%9A%E5%9B%9B%E5%B7%9D%EF%BC%8C%E5%8C%97%E9%80%9A%E9%99%95%E8%A5%BF%EF%BC%8C%E5%8D%97%E8%BE%BE%E5%B7%B4%E4%B8%9C%E4%B8%8E%E9%95%BF%E6%B1%9F%E4%B8%89%E5%B3%A1%E7%9B%B8%E6%8E%A5%EF%BC%8C%E6%98%AF%E8%BF%9E%E9%80%9A%E5%B7%9D%E3%80%81%E9%84%82%E3%80%81%E9%99%95%E4%BA%A4%E9%80%9A%E7%9A%84%E4%B8%AD%E8%BD%AC%E7%AB%99%E3%80%82%E5%A4%A7%E4%B9%9D%E6%B9%96%E6%97%A2%E6%98%AF%E6%9C%A8%E6%9D%90%E5%9F%BA%E5%9C%B0%EF%BC%8C%E5%8F%88%E6%98%AF%E5%A4%A9%E7%84%B6%E7%89%A7%E5%9C%BA%E3%80%82%E5%90%84%E7%A7%8D%E7%BB%8F%E6%B5%8E%E6%9E%97%E6%9C%A8%E9%81%8D%E5%B8%83%E5%B1%B1%E9%87%8E%EF%BC%8C%E9%99%A4%E9%87%91%E4%B8%9D%E7%8C%B4%EF%BC%8C%E5%8D%8E%E5%8D%97%E8%99%8E%E7%AD%89%E7%8F%8D%E7%A8%80%E5%8A%A8%E7%89%A9%E5%A4%96%EF%BC%8C%E8%BF%98%E5%BB%BA%E6%9C%89%E4%BA%BA%E5%B7%A5%E5%85%BB%E9%B9%BF%E5%9C%BA%E3%80%82%E5%A4%A7%E4%B9%9D%E6%B9%96%E8%87%AA%E7%84%B6%E9%A3%8E%E5%85%89%E6%80%A1%E4%BA%BA%EF%BC%8C%E4%BC%A0%E8%AF%B4%E9%81%97%E5%9D%80%E4%BC%97%E5%A4%9A%EF%BC%8C%E4%B8%BB%E8%A6%81%E6%9C%89%EF%BC%9A%E6%B4%97%E9%A9%AC%E6%B1%A0%E3%80%81%E8%96%9B%E4%BB%81%E8%B4%B5%E5%90%8E%E8%A3%94%E3%80%81%E8%96%9B%E5%88%9A%E5%8F%8D%E5%91%A8%EF%BC%88%E6%AD%A6%E5%88%99%E5%A4%A9%E5%9B%BD%E5%8F%B7%EF%BC%89%E7%9A%84%E5%8D%81%E5%AD%97%E5%8F%B7%E3%80%81%E5%A8%98%E5%A8%98%E5%9D%9F%E3%80%81%E5%8D%B8%E7%94%B2%E5%A5%97%E7%AD%89%E9%81%97%E5%9D%80%E5%92%8C%E5%8F%A4%E8%BF%B9 我在使用URL.openStream()的时候后台报错，但没看出来报什么错，URL的内容是ht