response.sendRedirect的多次转的问题，感谢，出错了，

if ("".equals(username_html)) {
response.sendRedirect("showwrong.jsp?wrong=usernameisnull");
}

if ("".equals(password_html)) {
response.sendRedirect("showwrong.jsp?wrong=passwordisnull"); }
if ("".equals(repassword_html)) {
response.sendRedirect("showwrong.jsp?wrong=repasswordisnull"); }总是提示我第二个
response.sendRedirect("showwrong.jsp?wrong=passwordisnull");这句有错误，，是不是第一次满足转的条件，，代码继续执行，系统不知道到底转哪个呀？？出错信息为：Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:504)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:387)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:314)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:264)
javax.servlet.http.HttpServlet.service(HttpServlet.java:802)
root cause java.lang.IllegalStateException
org.apache.catalina.connector.ResponseFacade.sendRedirect(ResponseFacade.java:432)
org.apache.jsp.newuser_jsp._jspService(newuser_jsp.java:141)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:97)感谢