请问下：在servlet和applet通信 servlet传序列化地想的问题

Question

请问下：在servlet和applet通信时 HttpURLConnection 对象的getInputStream 为什么一直报
 Server returned HTTP response code: 500 for URL:
at sun.net. www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
可以正常的从applet将序列化对象传到servlet，但是从servlet传过来就收不到啦java.io.IOException: Server returned HTTP response code: 500 for URL: http://localhost:8888/servlet/test?role=select
at sun.net.www.protocol.http.HttpURLConnection.getInputStream(Unknown Source)
at com.zcsoft.test.employee.ui.EmployeeFrame.initEmployees(EmployeeFrame.java:158)
at com.zcsoft.test.employee.ui.EmployeeFrame.init(EmployeeFrame.java:109)
at com.zcsoft.test.employee.ui.EmployeeFrame.<init>(EmployeeFrame.java:37)
at com.zcsoft.test.employee.ui.EmployeeFrame.main(EmployeeFrame.java:215)从applet传出去的servlet能正常接收

Answer 1

servlet返回的内容不对, 或者没有返回的内容. 把响应http://localhost:8888/servlet/test?role=select的servlet代码贴出来看看.