ServletActionContext.getRequest()空指针问题

ServletActionContext.getRequest()空指针问题

我的表单内部有按钮，还有视图选择框，

当点击“视图选择框”，选择视图中一条记录后，系统会执行void cn.myapps.core.dynaform.activity.ejb.ActivityType.addButton(String innerText, String function, String className, int permissionType)
的以下代码：

1.                 HttpSession session = ServletActionContext.getRequest().getSession();
   
2.                 String skinType = (String) session.getAttribute("SKINTYPE");
   
3.                 if (skinType != null && !skinType.equals("") && skinType.equals("gray")) {
   
4.                         htmlBuilder.append("<input icon='icon-save' type='button' ");
   
5.                         htmlBuilder.append(" name='" + getButtonId() + "'");
   
6.                         htmlBuilder.append(" title='" + act.getName() + "'");
   
7.                         if (PermissionType.MODIFY == permissionType) {
   
8.                                 htmlBuilder.append(" onclick="" + function + """);
   
9.                         }
   
10.                         if (PermissionType.DISABLED == permissionType) {
    
11.                                 htmlBuilder.append(" disabled='disabled'");
    
12.                         }
    
13.                         htmlBuilder.append(" value='" + innerText + "'>&nbsp;&nbsp;");
    
14.                 }

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可是，调试这段代码时候，发现ServletActionContext.getRequest()是空指针了？
执行完这段代码后，报出异常：

1. java.lang.NullPointerException
   
2.         at cn.myapps.core.dynaform.activity.ejb.ActivityType.addButton(ActivityType.java:403)
   
3.         at cn.myapps.core.dynaform.activity.ejb.ActivityType.toButtonHtml(ActivityType.java:316)
   
4.         at cn.myapps.core.dynaform.activity.ejb.Activity.toButtonHtml(Activity.java:835)
   
5.         at cn.myapps.core.dynaform.form.ejb.ButtonField.toHtmlTxt(ButtonField.java:121)
   
6.         at cn.myapps.core.dynaform.form.ejb.FormField.getRefreshScript(FormField.java:1225)
   
7.         at cn.myapps.core.dynaform.form.ejb.TabNormal.getRefreshScript(TabNormal.java:393)
   
8.         at cn.myapps.core.dynaform.form.ejb.TabField.getRefreshScript(TabField.java:190)
   
9.         at cn.myapps.core.dynaform.form.action.FormHelper.refresh(FormHelper.java:558)
   
10.         at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    
11.         at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
    
12.         at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
    
13.         at java.lang.reflect.Method.invoke(Method.java:589)
    
14.         at uk.ltd.getahead.dwr.impl.ExecuteQuery.execute(ExecuteQuery.java:239)
    
15.         at uk.ltd.getahead.dwr.impl.DefaultExecProcessor.handle(DefaultExecProcessor.java:48)
    
16.         at uk.ltd.getahead.dwr.impl.DefaultProcessor.handle(DefaultProcessor.java:81)
    
17.         at uk.ltd.getahead.dwr.AbstractDWRServlet.doPost(AbstractDWRServlet.java:162)
    
18.         at javax.servlet.http.HttpServlet.service(HttpServlet.java:710)
    
19.         at javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
    
20.         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:290)
    
21.         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    
22.         at cn.myapps.base.web.dwr.filter.DWRFilter.doFilter(DWRFilter.java:44)
    
23.         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    
24.         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    
25.         at com.opensymphony.webwork.dispatcher.FilterDispatcher.doFilter(FilterDispatcher.java:177)
    
26.         at cn.myapps.base.web.filter.OBPMFilterDispatcher.doFilter(OBPMFilterDispatcher.java:43)
    
27.         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    
28.         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    
29.         at cn.myapps.base.web.filter.AjaxMultiLanguageFilter.doFilter(AjaxMultiLanguageFilter.java:40)
    
30.         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    
31.         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    
32.         at cn.myapps.base.web.filter.PersistenceFilter.doFilter(PersistenceFilter.java:30)
    
33.         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    
34.         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    
35.         at cn.myapps.base.web.filter.SecurityFilter.doFilter(SecurityFilter.java:72)
    
36.         at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:235)
    
37.         at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:206)
    
38.         at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:233)
    
39.         at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:175)
    
40.         at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:128)
    
41.         at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:102)
    
42.         at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:109)
    
43.         at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:263)
    
44.         at org.apache.coyote.http11.Http11AprProcessor.process(Http11AprProcessor.java:852)
    
45.         at org.apache.coyote.http11.Http11AprProtocol$Http11ConnectionHandler.process(Http11AprProtocol.java:584)
    
46.         at org.apache.tomcat.util.net.AprEndpoint$Worker.run(AprEndpoint.java:1508)
    
47.         at java.lang.Thread.run(Thread.java:619)
    
48. 23:02:03,921  WARN DefaultExecProcessor:59 - Erroring: id[4503_1303830123531] message[uk.ltd.getahead.dwr.OutboundVariable@cfd69]
    

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你好，你的问题已收到，但暂时我处理不了，但我会尽快将你的问题转给其他技术人员，给您造成的不便敬请谅解。

HttpSession session =getContext().getSession();
这样获取session试试

回复 3# cynthia1


    这样改是否合适，怎么会出现这样一个空指针的问题的？

回复 3# cynthia1


    这样改不行的呀。The method getContext() is undefined for the type ActivityType

你这问题先等等，我让同事帮你跟进

对了，你是更改了原代码吗

回复 7# cynthia1


   没有呀，没有更改任何代码

回复 7# cynthia1


    有人说这段代码不能在ejb包里面访问session，session会不确定的消亡呀，怎么办？