把回车换成"\n",给你一段例子:
假设你输入文章的表单名叫article,则:String content=request.getParameter("article");
String contentc="";
int find=0;
int lastfind=0;
while(find!=-1)
{   find=content.indexOf("\n",find+1);
  
// out.print(Integer.toString(find));
  if(find==-1)
    {
    find=content.length();
    contentc+=content.substring(lastfind,find);
    find=-1;
    }
else{ 
contentc+=content.substring(lastfind,find);
}
contentc+="<br><br>";
lastfind=find;
}