textarea替换回车换行空格

while(jianjie.indexOf("\n")!=-1){
jianjie = jianjie.substring(0,jianjie.indexOf("\n"))+"<br>"+jianjie.substring(jianjie.indexOf("\n")+1);
}
while(jianjie.indexOf(" ")!=-1){
jianjie = jianjie.substring(0,jianjie.indexOf(" "))+"&nbsp;"+jianjie.substring(jianjie.indexOf(" ")+1);
}
out.println(jianjie);