这是什么情况？只是说For input string: "null1"]我该怎么改；

Question

严重: Servlet.service() for servlet [jsp] in context with path [/Shopping_web] threw exception [java.lang.NumberFormatException: For input string: "null1"] with root cause

java.lang.NumberFormatException: For input string: "null1"

at java.lang.NumberFormatException.forInputString(NumberFormatException.java:65)

at java.lang.Integer.parseInt(Integer.java:580)

at java.lang.Integer.parseInt(Integer.java:615)

at Dao.itemDao.getViewList(itemDao.java:117)

at org.apache.jsp.detail_jsp._jspService(detail_jsp.java:192)

at org.apache.jasper.runtime.HttpJspBase.service(HttpJspBase.java:70)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)

at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:443)

at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:385)

at org.apache.jasper.servlet.JspServlet.service(JspServlet.java:329)

at javax.servlet.http.HttpServlet.service(HttpServlet.java:729)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:230)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)

at org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:52)

at org.apache.catalina.core.ApplicationFilterChain.internalDoFilter(ApplicationFilterChain.java:192)

at org.apache.catalina.core.ApplicationFilterChain.doFilter(ApplicationFilterChain.java:165)

at org.apache.catalina.core.StandardWrapperValve.invoke(StandardWrapperValve.java:198)

at org.apache.catalina.core.StandardContextValve.invoke(StandardContextValve.java:96)

at org.apache.catalina.authenticator.AuthenticatorBase.invoke(AuthenticatorBase.java:474)

at org.apache.catalina.core.StandardHostValve.invoke(StandardHostValve.java:140)

at org.apache.catalina.valves.ErrorReportValve.invoke(ErrorReportValve.java:79)

at org.apache.catalina.valves.AbstractAccessLogValve.invoke(AbstractAccessLogValve.java:624)

at org.apache.catalina.core.StandardEngineValve.invoke(StandardEngineValve.java:87)

at org.apache.catalina.connector.CoyoteAdapter.service(CoyoteAdapter.java:349)

at org.apache.coyote.http11.Http11Processor.service(Http11Processor.java:783)

at org.apache.coyote.AbstractProcessorLight.process(AbstractProcessorLight.java:66)

at org.apache.coyote.AbstractProtocol$ConnectionHandler.process(AbstractProtocol.java:789)

at org.apache.tomcat.util.net.NioEndpoint$SocketProcessor.doRun(NioEndpoint.java:1437)

at org.apache.tomcat.util.net.SocketProcessorBase.run(SocketProcessorBase.java:49)

at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)

at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)

at org.apache.tomcat.util.threads.TaskThread$WrappingRunnable.run(TaskThread.java:61)

at java.lang.Thread.run(Thread.java:745)

Answer 1

先判断字符串能不能转化成为数字,不能就过