java.lang.NullPointerException 在 org.apache.jsp.init_jsp.jspInit(init_jsp.java:39)

Question

我正在用 intellij 和 Maven 编写一个 java webapp。当我尝试在 tomcat 7 上部署 webapp 时，出现以下异常

不要将此标记为 NullPointerException 的副本，因为这是关于 jsp 错误的。

SEVERE: Servlet /SynapseChat threw load() exception
java.lang.NullPointerException
at org.apache.jsp.init_jsp.jspInit(init_jsp.java:39)
at org.apache.jasper.runtime.HttpJspBase.init(HttpJspBase.java:48)
at org.apache.jasper.servlet.JspServletWrapper.getServlet(JspServletWrapper.java:180)
at org.apache.jasper.servlet.JspServletWrapper.service(JspServletWrapper.java:369)
at org.apache.jasper.servlet.JspServlet.serviceJspFile(JspServlet.java:395)
at org.apache.jasper.servlet.JspServlet.init(JspServlet.java:138)
at org.apache.catalina.core.StandardWrapper.initServlet(StandardWrapper.java:1284)
at org.apache.catalina.core.StandardWrapper.loadServlet(StandardWrapper.java:1197)
at org.apache.catalina.core.StandardWrapper.load(StandardWrapper.java:1087)
at org.apache.catalina.core.StandardContext.loadOnStartup(StandardContext.java:5231)
at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5518)
at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:150)
at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:901)
at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:877)
at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:649)
at org.apache.catalina.startup.HostConfig.manageApp(HostConfig.java:1762)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:301)
at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:618)
at org.apache.catalina.mbeans.MBeanFactory.createStandardContext(MBeanFactory.java:565)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at org.apache.tomcat.util.modeler.BaseModelMBean.invoke(BaseModelMBean.java:301)
at com.sun.jmx.interceptor.DefaultMBeanServerInterceptor.invoke(DefaultMBeanServerInterceptor.java:819)
at com.sun.jmx.mbeanserver.JmxMBeanServer.invoke(JmxMBeanServer.java:801)
at javax.management.remote.rmi.RMIConnectionImpl.doOperation(RMIConnectionImpl.java:1487)
at javax.management.remote.rmi.RMIConnectionImpl.access0(RMIConnectionImpl.java:97)
at javax.management.remote.rmi.RMIConnectionImpl$PrivilegedOperation.run(RMIConnectionImpl.java:1328)
at javax.management.remote.rmi.RMIConnectionImpl.doPrivilegedOperation(RMIConnectionImpl.java:1420)
at javax.management.remote.rmi.RMIConnectionImpl.invoke(RMIConnectionImpl.java:848)
at sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
at sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:57)
at sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
at java.lang.reflect.Method.invoke(Method.java:606)
at sun.rmi.server.UnicastServerRef.dispatch(UnicastServerRef.java:322)
at sun.rmi.transport.Transport.run(Transport.java:202)
at sun.rmi.transport.Transport.run(Transport.java:199)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.Transport.serviceCall(Transport.java:198)
at sun.rmi.transport.tcp.TCPTransport.handleMessages(TCPTransport.java:567)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run0(TCPTransport.java:828)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.access0(TCPTransport.java:619)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:684)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:681)
at java.security.AccessController.doPrivileged(Native Method)
at sun.rmi.transport.tcp.TCPTransport$ConnectionHandler.run(TCPTransport.java:681)
at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1145)
at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:615)
at java.lang.Thread.run(Thread.java:745)

我尝试了所有类似的问题，但找不到可行的解决方案。我检查了我的 WEB-INF/lib 文件夹中可能存在冲突的 jar，但找不到答案中提到的任何内容。这是我的 WEB-INF/lib 文件夹

中的罐子列表

ampcore-1.0.7.5.jar
aopalliance-repackaged-2.4.0-b31.jar
gson-2.4.jar
hk2-api-2.4.0-b31.jar
hk2-locator-2.4.0-b31.jar
hk2-utils-2.4.0-b31.jar
javassist-3.18.1-GA.jar
javax.annotation-api-1.2.jar
javax.inject-2.4.0-b31.jar
javax.ws.rs-api-2.0.1.jar
jdom-1.1.2.jar
jersey-client-2.22.1.jar
球衣-common-2.22.1.jar
jersey-container-servlet-2.22.1.jar
jersey-container-servlet-core-2.22.1.jar
jersey-guava-2.22.1.jar
jersey-media-jaxb-2.22.1.jar
jersey-server-2.22.1.jar
jxmpp-core-0.4.2.jar
jxmpp-util-cache-0.4.2.jar
log4j-1.2.12.jar
logger-1.0.0.jar
mysql-连接器-java-5.1.6.jar
osgi-resource-locator-1.0.1.jar
rest-api-client-1.1.3.jar
slf4j-api-1.7.12.jar
slf4j-simple-1.7.12.jar
smack-core-4.1.4.jar
smack-im-4.1.4.jar
smack-tcp-4.1.4.jar
验证-api-1.1.0.Final.jar
xmlconfreader-1.0.0.jar
xpp3-1.1.4c.jar

这是我的 init.jsp 代码。

<%@page import="java.lang.*"%>
<%@ page import="java.util.*" %>
<%@ page import="java.io.*" %>

<%@ page import="java.net.URLEncoder" %>
<%@ page import="org.jdom.*" %>
<%@ page import="synapse.ivr.logger.*" %>
<%@ page import="java.io.File" %>
<%@ page import="org.apache.log4j.BasicConfigurator" %>
<%@ page import="org.apache.log4j.PropertyConfigurator" %>
<%@ page import="synapse.ivr.xmlreader.SystemConfig" %>
<%@ page import="org.apache.log4j.Logger" %>

<%
    jspInit();
%>
<%!public void jspInit(){

    System.out.println("START INITIALIZING AMP API");

    LoggerConguratorXML.DEFAULT_FILE =  "/etc/cms/chatapi/log4j.xml";
    LoggerConguratorXML.loggerConfig();

    SystemConfig.DEFAULT_FILE =  "/etc/cms/chatapi/config.xml";
    SystemConfig.getInstance();

    String softVersion =    SystemConfig.getInstance().getStr("ivr.chatserver.version").toString();

    GlobleLogging synapseUMS = new GlobleLogging();
    Logger cat = synapseUMS.returnLogger();

    cat.info("Config files initiated");
    cat.info("SW Version : "+softVersion);
    System.out.println("SW Version : "+softVersion);
    System.out.println("##############################################");


}%>

Answer 1

SystemConfig.getInstance().getStr("ivr.chatserver.version") 可能为空，在这种情况下调用 .toString() 会导致这种行为。

虽然它仍然是 What is a NullPointerException, and how do I fix it? 的副本。

java.lang.NullPointerException 在 org.apache.jsp.init_jsp.jspInit(init_jsp.java:39)

java.lang.NullPointerException at org.apache.jsp.init_jsp.jspInit(init_jsp.java:39)

java

maven

web-applications

intellij-idea

tomcat7