단일 서블릿에서 여러 DAO 호출

Question

누구나 다중 데이터 액세스 개체에서 개체를 만들고 해당 메서드를 호출하는 방법을 알고 있습니다. 난 단 하나의 DAO에서 개체를 만든 다음 자신의 메서드를 호출 할 때 그것은 완벽하게 작동하지만 여러으로는 널 포인터 예외가 발생,

을 여기에 내가

java.lang.NullPointerException at front.Home.processRequest(Home.java:70) at front.Home.doGet(Home.java:97) at javax.servlet.http.HttpServlet.service(HttpServlet.java:687) at javax.servlet.http.HttpServlet.service(HttpServlet.java:790) at org.apache.catalina.core.StandardWrapper.service(StandardWrapper.java:1682) at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:318) at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:160) at org.apache.catalina.core.StandardPipeline.doInvoke(StandardPipeline.java:734) at org.apache.catalina.core.StandardPipeline.invoke(StandardPipeline.java:673) at com.sun.enterprise.web.WebPipeline.invoke(WebPipeline.java:99) at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:174) at org.apache.catalina.connector.CoyoteAdapter.doService(CoyoteAdapter.java:357) at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:260) at com.sun.enterprise.v3.services.impl.ContainerMapper.service(ContainerMapper.java:188) at org.glassfish.grizzly.http.server.HttpHandler.runService(HttpHandler.java:191) at org.glassfish.grizzly.http.server.HttpHandler.doHandle(HttpHandler.java:168) at org.glassfish.grizzly.http.server.HttpServerFilter.handleRead(HttpServerFilter.java:189) at org.glassfish.grizzly.filterchain.ExecutorResolver$9.execute(ExecutorResolver.java:119) at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeFilter(DefaultFilterChain.java:288) at org.glassfish.grizzly.filterchain.DefaultFilterChain.executeChainPart(DefaultFilterChain.java:206) at org.glassfish.grizzly.filterchain.DefaultFilterChain.execute(DefaultFilterChain.java:136) at org.glassfish.grizzly.filterchain.DefaultFilterChain.process(DefaultFilterChain.java:114) at org.glassfish.grizzly.ProcessorExecutor.execute(ProcessorExecutor.java:77) at org.glassfish.grizzly.nio.transport.TCPNIOTransport.fireIOEvent(TCPNIOTransport.java:838) at org.glassfish.grizzly.strategies.AbstractIOStrategy.fireIOEvent(AbstractIOStrategy.java:113) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.run0(WorkerThreadIOStrategy.java:115) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy.access$100(WorkerThreadIOStrategy.java:55) at org.glassfish.grizzly.strategies.WorkerThreadIOStrategy$WorkerThreadRunnable.run(WorkerThreadIOStrategy.java:135) at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.doWork(AbstractThreadPool.java:564) at org.glassfish.grizzly.threadpool.AbstractThreadPool$Worker.run(AbstractThreadPool.java:544) at java.lang.Thread.run(Thread.java:744) 

Answer 1

주석이 점점 오전 오류입니다 단일 필드, 클래스 또는 메소드에만 적용되므로 모든 종속 항목에 별도로 주석을 달아야합니다.