Go语言视频零基础入门到精通

dmweji

java.lang.NullPointerException

    at com.szjz.system.serviceImpl.UserManagementAddServiceImpl.AddUser(UserManagementAddServiceImpl.java:24)

    at com.szjz.system.action.UserManagementAddAction.doExecute(UserManagementAddAction.java:84)

    at com.szjz.system.utils.BaseAction.execute(BaseAction.java:22)

    at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)

    at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)

    at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)

    at com.szjz.system.utils.MyActionServlet.doPost(MyActionServlet.java:38)

    at javax.servlet.http.HttpServlet.service(HttpServlet.java:637)

    at javax.servlet.http.HttpServlet.service(HttpServlet.java:717)

    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)

    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)

    at com.szjz.system.utils.EncodingFilter.doFilter(EncodingFilter.java:29)

    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)

    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)

    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)

    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:191)

    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)

    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)

    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)

    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:286)

    at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:857)

    at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:565)

    at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1509)

    at java.lang.Thread.run(Thread.java:595)



解决方法：第一种：将你需要注入的参数设置为static的，然后将设值方法setXXX的返回值设置为非void型，比如你的

protected IDaoService daoService;   //注入类的属性

改为

protected static IDaoService daoService;   //注入类的属性