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自定义对象列表不能在运行时添加对象给出“空指针异常”

2012-12-06 43 views
0

我在创建自定义类型对象列表的一个列表并在该列表中添加一些对象时遇到了一些问题。 我有一个advertise对象列表自定义对象列表不能在运行时添加对象给出“空指针异常”

public int ajax_GenerateReports(ResourceRequest request, ResourceResponse response) throws Exception { 

    log.info("ajax_Generate Reports Enter"); 

    String strcamp_id = request.getParameter("CMD"); 

    log.info("ajax_Generate Reports Enter"+strcamp_id); 

    long camp_id = Long.parseLong(strcamp_id); 

    log.info("camp_ID:-"+ camp_id); 

    int iResult = 1; 

    List<campaign_map_adv> camp_map_adv_List = null; 

    List<advertise> adv_List = null; 

    camp_map_adv_List = campaign_map_advLocalServiceUtil.getAllCamp_Map_Adv_By_campID(camp_id); 

    log.info("CAMPIAGN MAP OBJECT : - "+ camp_map_adv_List.get(0)); 
    log.info("CAMPIAGN MAP OBJECT List Count : - "+ camp_map_adv_List.size()); 

    if(!camp_map_adv_List.isEmpty()) { //Search For Each Camp entry in camp_map Adv 

     for (campaign_map_adv campaign_map_advitem : camp_map_adv_List) {     
      //add each advertise to temporary list file of advertise from camp_map_adv 
      advertise temp_ad = advertiseLocalServiceUtil.getadvertise(campaign_map_advitem.getAdvId()); 

      adv_List.add(temp_ad); 
     } 

    } 
    //   

    //////////////// 
    System.setProperty("java.awt.headless", "true"); 
    System.out.println(java.awt.GraphicsEnvironment.isHeadless()); 
    System.out.println("IN GENRATE REPORTS "); 

    System.out.println("IN GENRATE LIST " +adv_List.size()); 

    JRBeanCollectionDataSource beanCollectionDataSource = new JRBeanCollectionDataSource(adv_List); 

    System.out.println(" bean collection " + beanCollectionDataSource.getRecordCount()); 

    System.out.println("Test!!"); 

    JasperPrint jasperPrint = JasperFillManager 
      .fillReport(
        "C:/liferay/tomcat-7.0.27/webapps/eMenuAdvertise-portlet/src_reports/report3.jasper", 
        new HashMap<String, Object>(), beanCollectionDataSource); 

    System.out.println(" report path "); 
    JasperExportManager.exportReportToHtmlFile(jasperPrint, "c:/liferay/report.html"); 

    /////////////// 

    log.info("ajax_GenerateReports Leave"); 

    return iResult; 
}

从以下行开始我的代码具有运行时错误插入第一个对象后：

advertise temp_ad = advertiseLocalServiceUtil.getadvertise(campaign_map_advitem.getAdvId()); 

adv_List.add(temp_ad);

因此，如果任何人都可以指导我...

堆栈跟踪： -

18:32:21,719 INFO [http-bio-8080-exec-56][RestaurantPortlet:2311] serveResource Start 
18:32:21,746 INFO [http-bio-8080-exec-56][RestaurantPortlet:2322] Resource Id - generate_report 
18:32:21,747 INFO [http-bio-8080-exec-56][RestaurantPortlet:2225] ajax_Generate Reports Enter 
18:32:21,747 INFO [http-bio-8080-exec-56][RestaurantPortlet:2228] ajax_Generate Reports Enter22901 
18:32:21,747 INFO [http-bio-8080-exec-56][RestaurantPortlet:2230] camp_ID:-22901 
18:32:21,778 INFO [http-bio-8080-exec-56][RestaurantPortlet:2237] CAMPIAGN MAP OBJECT : - {id=22902, campaignId=22901, advId=18726, restId=15101, isactive=true, adtypeId=4} 
18:32:21,779 INFO [http-bio-8080-exec-56][RestaurantPortlet:2238] CAMPIAGN MAP OBJECT : - 7 
java.lang.NullPointerException 
    at emenu.advertise.portlet.RestaurantPortlet.ajax_GenerateReports(RestaurantPortlet.java:2248) 
    at emenu.advertise.portlet.RestaurantPortlet.serveResource(RestaurantPortlet.java:2437) 
    at com.liferay.portlet.FilterChainImpl.doFilter(FilterChainImpl.java:118) 
    at com.liferay.portal.kernel.portlet.PortletFilterUtil.doFilter(PortletFilterUtil.java:71) 
    at com.liferay.portal.kernel.servlet.PortletServlet.service(PortletServlet.java:111) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:72) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilter.doFilter(InvokerFilter.java:73) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684) 
    at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:471) 
    at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:402) 
    at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:329) 
    at com.liferay.portlet.InvokerPortletImpl.invoke(InvokerPortletImpl.java:531) 
    at com.liferay.portlet.InvokerPortletImpl.invokeResource(InvokerPortletImpl.java:626) 
    at com.liferay.portlet.InvokerPortletImpl.serveResource(InvokerPortletImpl.java:436) 
    at com.liferay.portal.action.LayoutAction.processPortletRequest(LayoutAction.java:1075) 
    at com.liferay.portal.action.LayoutAction.processLayout(LayoutAction.java:719) 
    at com.liferay.portal.action.LayoutAction.execute(LayoutAction.java:249) 
    at org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431) 
    at org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236) 
    at com.liferay.portal.struts.PortalRequestProcessor.process(PortalRequestProcessor.java:176) 
    at org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196) 
    at org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:621) 
    at com.liferay.portal.servlet.MainServlet.callParentService(MainServlet.java:560) 
    at com.liferay.portal.servlet.MainServlet.service(MainServlet.java:537) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:72) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:163) 
    at com.liferay.portal.servlet.filters.secure.SecureFilter.processFilter(SecureFilter.java:294) 
    at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:57) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilter.doFilter(InvokerFilter.java:73) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    at org.apache.catalina.core.ApplicationDispatcher.invoke(ApplicationDispatcher.java:684) 
    at org.apache.catalina.core.ApplicationDispatcher.processRequest(ApplicationDispatcher.java:471) 
    at org.apache.catalina.core.ApplicationDispatcher.doForward(ApplicationDispatcher.java:402) 
    at org.apache.catalina.core.ApplicationDispatcher.forward(ApplicationDispatcher.java:329) 
    at com.liferay.portal.servlet.FriendlyURLServlet.service(FriendlyURLServlet.java:138) 
    at javax.servlet.http.HttpServlet.service(HttpServlet.java:722) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:305) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:72) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:163) 
    at com.liferay.portal.servlet.filters.gzip.GZipFilter.processFilter(GZipFilter.java:123) 
    at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:57) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:163) 
    at com.liferay.portal.servlet.filters.secure.SecureFilter.processFilter(SecureFilter.java:294) 
    at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:57) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:163) 
    at com.liferay.portal.servlet.filters.i18n.I18nFilter.processFilter(I18nFilter.java:241) 
    at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:57) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:163) 
    at com.liferay.portal.servlet.filters.autologin.AutoLoginFilter.processFilter(AutoLoginFilter.java:246) 
    at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:57) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:163) 
    at com.liferay.portal.servlet.filters.sso.ntlm.NtlmPostFilter.processFilter(NtlmPostFilter.java:83) 
    at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:57) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:163) 
    at com.liferay.portal.sharepoint.SharepointFilter.processFilter(SharepointFilter.java:80) 
    at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:57) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.BaseFilter.processFilter(BaseFilter.java:163) 
    at com.liferay.portal.servlet.filters.virtualhost.VirtualHostFilter.processFilter(VirtualHostFilter.java:216) 
    at com.liferay.portal.kernel.servlet.BaseFilter.doFilter(BaseFilter.java:57) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDirectCallFilter(InvokerFilterChain.java:187) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:95) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at org.tuckey.web.filters.urlrewrite.UrlRewriteFilter.doFilter(UrlRewriteFilter.java:738) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDoFilter(InvokerFilterChain.java:206) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:108) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDirectCallFilter(InvokerFilterChain.java:167) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:95) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDirectCallFilter(InvokerFilterChain.java:167) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:95) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:116) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.processDirectCallFilter(InvokerFilterChain.java:187) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilterChain.doFilter(InvokerFilterChain.java:95) 
    at com.liferay.portal.kernel.servlet.filters.invoker.InvokerFilter.doFilter(InvokerFilter.java:73) 
    at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:243) 
    at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:210) 
    at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:225) 
    at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:169) 
    at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:472) 
    at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:168) 
    at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:98) 
    at org.apache.catalina.valves.AccessLogValve.invoke(AccessLogValve.java:927) 
    at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:118) 
    at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:407) 
    at org.apache.coyote.http11.AbstractHttp11Processor.process(AbstractHttp11Processor.java:999) 
    at org.apache.coyote.AbstractProtocol$AbstractConnectionHandler.process(AbstractProtocol.java:565) 
    at org.apache.tomcat.util.net.JIoEndpoint$SocketProcessor.run(JIoEndpoint.java:309) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.runTask(ThreadPoolExecutor.java:886) 
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:908) 
    at java.lang.Thread.run(Thread.java:619)

来源

2012-12-06 Bhavik Kama

+0

您声明“从插入第一个对象之后，我的代码有运行时错误”，这是否意味着您可以成功添加至少一个“advertise”对象到您的“adv_List”中？ – 2012-12-06 14:46:00

+0

您能否提供异常的相关堆栈跟踪？谢谢 –

+0

no @ rhod我只是在adv之前得到异常）List.add（temp_ad）; –

回答

0

你回答了你自己的问题问题在this comment。

所以考虑到这一点在堆栈跟踪行RestaurantPortlet.java:2248是：

adv_List.add(temp_ad); // I m guessing this might be the line: 2248

我觉得这只是你可能会错过实例化adv_List监督，你目前有：

List<advertise> adv_List = null;

之后就没有东西了，直接打电话adv_List.add(temp_ad);，相反我们可以有：

List<advertise> adv_List = new ArrayList<advertise>();

我想这应该解决它，这是很简单的:-)

无关的问题：奇怪的是看你的类名称为小写（如advertise，campaign_map_adv等等），这使得它很难阅读，而不是标准的Java约定。因为这个，你必须使用带下划线的变量，这是另一种痛苦。

来源

2012-12-07 11:46:19

+0

雅我知道..但因为我已经创建了我的实体名称与小写..它生成所有类与小写..这是我的第一个porltet和ddnt知道，给实体名称作为小写会创建名称小写为该类.. –

+0

我们可以聊天的同时有一些问题..所以我如果你有时间，那么请 –

+0

HTTP：//聊天。 stackoverflow.com/rooms/info/20749/for-date-time-format-in-java?tab=general –

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