是这样的,我用的是Intellij 导入了一个MyEclipse的包(该包已部署在服务器上，所以是没有大错误的)。
然后在一个jsp文件出现了个问题：
莫名奇妙地println变成了红色，执行的时候就直接抛出异常了。
今天刚接触JavaWeb不太懂，到底是怎么回事呢？
异常：
type Exception report
message An exception occurred processing JSP page /blackphones.jsp at line 15
description The server encountered an internal error that prevented it from fulfilling this request.
exception
org.apache.jasper.JasperException: An exception occurred processing JSP page /blackphones.jsp at line 15
12:
13: String [] phones = (String []) request.getAttribute("blackphones");
14:
15: out.println("褰撳墠鏈� + phones.length + "涓墜鏈哄彿鐮侊細
");
16:
17: for(String phone : phones){
18: out.println(phone + " ");
Stacktrace:
org.apache.jasper.servlet.JspServletWrapper.handleJspException(JspServletWrapper.java:575)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:477)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:339)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
com.aspire.mmlite.server.servlet.LogFilter.doFilter(LogFilter.java:63)
root cause
java.lang.NullPointerException
org.apache.jsp.blackphones_jsp._jspService(blackphones_jsp.java:96)
org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:439)
org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395)
org.apache.jasper.servlet.JspServlet.service(JspServlet.java:339)
javax.servlet.http.HttpServlet.service(HttpServlet.java:731)
org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)
com.aspire.mmlite.server.servlet.LogFilter.doFilter(LogFilter.java:63)
