String s=request.getParameter("content");
s=s.replaceAll("<","<");
s=s.replaceAll(">",">");
s=s.replaceAll(" "," ");
s=s.replaceAll("\n","<br>");
s=s.replaceAll("<","<");
s=s.replaceAll(">",">");
s=s.replaceAll(" "," ");
s=s.replaceAll("\n","<br>");
s=s.replaceAll("\r\n","<br>");
这样写有问题的,如果输入很多
asf asdf asdf asdf asdf asdf asdf as 等等,
会把这些看成一个单词,从而出现错误。