Tomcat 8 cannot load website
<p>I am a newbie of java servlet programming and learning about this. The tomcat installed on my debian computer can initially display the default sample webpage. But after replacing the loading files in var/lib/tomcat8/webapps/ROOT with the example pages, the websites fail to show on port 8080.</p>

<p>Below are the output messages in catalina.out:</p>

<pre><code>Sep 28, 2016 10:08:31 PM org.apache.jasper.servlet.TldScanner scanJars
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
Sep 28, 2016 10:08:31 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deployment of configuration descriptor /etc/tomcat8/Catalina/localhost/examples.xml has finished in 694 ms
Sep 28, 2016 10:08:31 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor /etc/tomcat8/Catalina/localhost/docs.xml
Sep 28, 2016 10:08:31 PM org.apache.tomcat.util.scan.StandardJarScanner scan
WARNING: Failed to scan [file:/usr/share/java/el-api-3.0.jar] from classloader hierarchy
java.io.FileNotFoundException: /usr/share/java/el-api-3.0.jar (No such file or directory)
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:219)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:149)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:166)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:130)
    at org.apache.tomcat.util.scan.JarFileUrlJar.&lt;init&gt;(JarFileUrlJar.java:60)
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:43)
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:323)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:273)
    at org.apache.catalina.startup.ContextConfig.processJarsForWebFragments(ContextConfig.java:1898)
    at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1131)
    at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:783)
    at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:307)
    at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:95)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5213)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:587)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1798)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Sep 28, 2016 10:08:31 PM org.apache.tomcat.util.scan.StandardJarScanner scan
WARNING: Failed to scan [file:/usr/share/java/jsp-api-2.3.jar] from classloader hierarchy
java.io.FileNotFoundException: /usr/share/java/jsp-api-2.3.jar (No such file or directory)
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:219)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:149)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:166)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:130)
    at org.apache.tomcat.util.scan.JarFileUrlJar.&lt;init&gt;(JarFileUrlJar.java:60)
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:43)
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:323)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:273)
    at org.apache.catalina.startup.ContextConfig.processJarsForWebFragments(ContextConfig.java:1898)
    at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1131)
    at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:783)
    at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:307)
    at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:95)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5213)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:587)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1798)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Sep 28, 2016 10:08:32 PM org.apache.tomcat.util.scan.StandardJarScanner scan
WARNING: Failed to scan [file:/usr/share/java/el-api-3.0.jar] from classloader hierarchy
java.io.FileNotFoundException: /usr/share/java/el-api-3.0.jar (No such file or directory)
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:219)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:149)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:166)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:130)
    at org.apache.tomcat.util.scan.JarFileUrlJar.&lt;init&gt;(JarFileUrlJar.java:60)
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:43)
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:323)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:273)
    at org.apache.jasper.servlet.TldScanner.scanJars(TldScanner.java:262)
    at org.apache.jasper.servlet.TldScanner.scan(TldScanner.java:106)
    at org.apache.jasper.servlet.JasperInitializer.onStartup(JasperInitializer.java:103)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5303)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:587)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1798)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Sep 28, 2016 10:08:32 PM org.apache.tomcat.util.scan.StandardJarScanner scan
WARNING: Failed to scan [file:/usr/share/java/jsp-api-2.3.jar] from classloader hierarchy
java.io.FileNotFoundException: /usr/share/java/jsp-api-2.3.jar (No such file or directory)
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:219)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:149)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:166)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:130)
    at org.apache.tomcat.util.scan.JarFileUrlJar.&lt;init&gt;(JarFileUrlJar.java:60)
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:43)
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:323)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:273)
    at org.apache.jasper.servlet.TldScanner.scanJars(TldScanner.java:262)
    at org.apache.jasper.servlet.TldScanner.scan(TldScanner.java:106)
    at org.apache.jasper.servlet.JasperInitializer.onStartup(JasperInitializer.java:103)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5303)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:587)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1798)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Sep 28, 2016 10:08:32 PM org.apache.jasper.servlet.TldScanner scanJars
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
Sep 28, 2016 10:08:32 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deployment of configuration descriptor /etc/tomcat8/Catalina/localhost/docs.xml has finished in 410 ms
Sep 28, 2016 10:08:32 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deploying configuration descriptor /etc/tomcat8/Catalina/localhost/host-manager.xml
Sep 28, 2016 10:08:32 PM org.apache.tomcat.util.scan.StandardJarScanner scan
WARNING: Failed to scan [file:/usr/share/java/el-api-3.0.jar] from classloader hierarchy
java.io.FileNotFoundException: /usr/share/java/el-api-3.0.jar (No such file or directory)
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:219)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:149)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:166)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:130)
    at org.apache.tomcat.util.scan.JarFileUrlJar.&lt;init&gt;(JarFileUrlJar.java:60)
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:43)
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:323)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:273)
    at org.apache.catalina.startup.ContextConfig.processJarsForWebFragments(ContextConfig.java:1898)
    at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1131)
    at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:783)
    at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:307)
    at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:95)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5213)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:587)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1798)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Sep 28, 2016 10:08:32 PM org.apache.tomcat.util.scan.StandardJarScanner scan
WARNING: Failed to scan [file:/usr/share/java/jsp-api-2.3.jar] from classloader hierarchy
java.io.FileNotFoundException: /usr/share/java/jsp-api-2.3.jar (No such file or directory)
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:219)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:149)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:166)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:130)
    at org.apache.tomcat.util.scan.JarFileUrlJar.&lt;init&gt;(JarFileUrlJar.java:60)
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:43)
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:323)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:273)
    at org.apache.catalina.startup.ContextConfig.processJarsForWebFragments(ContextConfig.java:1898)
    at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1131)
    at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:783)
    at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:307)
    at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:95)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5213)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:587)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1798)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Sep 28, 2016 10:08:32 PM org.apache.tomcat.util.scan.StandardJarScanner scan
WARNING: Failed to scan [file:/usr/share/java/el-api-3.0.jar] from classloader hierarchy
java.io.FileNotFoundException: /usr/share/java/el-api-3.0.jar (No such file or directory)
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:219)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:149)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:166)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:130)
    at org.apache.tomcat.util.scan.JarFileUrlJar.&lt;init&gt;(JarFileUrlJar.java:60)
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:43)
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:323)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:273)
    at org.apache.jasper.servlet.TldScanner.scanJars(TldScanner.java:262)
    at org.apache.jasper.servlet.TldScanner.scan(TldScanner.java:106)
    at org.apache.jasper.servlet.JasperInitializer.onStartup(JasperInitializer.java:103)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5303)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:587)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1798)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Sep 28, 2016 10:08:32 PM org.apache.tomcat.util.scan.StandardJarScanner scan
WARNING: Failed to scan [file:/usr/share/java/jsp-api-2.3.jar] from classloader hierarchy
java.io.FileNotFoundException: /usr/share/java/jsp-api-2.3.jar (No such file or directory)
    at java.util.zip.ZipFile.open(Native Method)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:219)
    at java.util.zip.ZipFile.&lt;init&gt;(ZipFile.java:149)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:166)
    at java.util.jar.JarFile.&lt;init&gt;(JarFile.java:130)
    at org.apache.tomcat.util.scan.JarFileUrlJar.&lt;init&gt;(JarFileUrlJar.java:60)
    at org.apache.tomcat.util.scan.JarFactory.newInstance(JarFactory.java:43)
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:323)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:273)
    at org.apache.jasper.servlet.TldScanner.scanJars(TldScanner.java:262)
    at org.apache.jasper.servlet.TldScanner.scan(TldScanner.java:106)
    at org.apache.jasper.servlet.JasperInitializer.onStartup(JasperInitializer.java:103)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5303)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDescriptor(HostConfig.java:587)
    at org.apache.catalina.startup.HostConfig$DeployDescriptor.run(HostConfig.java:1798)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)

Sep 28, 2016 10:08:32 PM org.apache.jasper.servlet.TldScanner scanJars
INFO: At least one JAR was scanned for TLDs yet contained no TLDs. Enable debug logging for this logger for a complete list of JARs that were scanned but no TLDs were found in them. Skipping unneeded JARs during scanning can improve startup time and JSP compilation time.
Sep 28, 2016 10:08:32 PM org.apache.catalina.startup.HostConfig deployDescriptor
INFO: Deployment of configuration descriptor /etc/tomcat8/Catalina/localhost/host-manager.xml has finished in 395 ms
Sep 28, 2016 10:08:32 PM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deploying web application directory /var/lib/tomcat8/webapps/ROOT
Sep 28, 2016 10:08:32 PM org.apache.catalina.core.ContainerBase addChildInternal
SEVERE: ContainerBase.addChild: start: 
org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[]]
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:162)
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:725)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1092)
    at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1834)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
Caused by: java.lang.NullPointerException
    at org.apache.tomcat.util.scan.StandardJarScanner.process(StandardJarScanner.java:322)
    at org.apache.tomcat.util.scan.StandardJarScanner.scan(StandardJarScanner.java:182)
    at org.apache.catalina.startup.ContextConfig.processJarsForWebFragments(ContextConfig.java:1898)
    at org.apache.catalina.startup.ContextConfig.webConfig(ContextConfig.java:1131)
    at org.apache.catalina.startup.ContextConfig.configureStart(ContextConfig.java:783)
    at org.apache.catalina.startup.ContextConfig.lifecycleEvent(ContextConfig.java:307)
    at org.apache.catalina.util.LifecycleSupport.fireLifecycleEvent(LifecycleSupport.java:95)
    at org.apache.catalina.util.LifecycleBase.fireLifecycleEvent(LifecycleBase.java:90)
    at org.apache.catalina.core.StandardContext.startInternal(StandardContext.java:5213)
    at org.apache.catalina.util.LifecycleBase.start(LifecycleBase.java:145)
    ... 10 more

Sep 28, 2016 10:08:32 PM org.apache.catalina.startup.HostConfig deployDirectory
SEVERE: Error deploying web application directory /var/lib/tomcat8/webapps/ROOT
java.lang.IllegalStateException: ContainerBase.addChild: start: org.apache.catalina.LifecycleException: Failed to start component [StandardEngine[Catalina].StandardHost[localhost].StandardContext[]]
    at org.apache.catalina.core.ContainerBase.addChildInternal(ContainerBase.java:729)
    at org.apache.catalina.core.ContainerBase.addChild(ContainerBase.java:701)
    at org.apache.catalina.core.StandardHost.addChild(StandardHost.java:717)
    at org.apache.catalina.startup.HostConfig.deployDirectory(HostConfig.java:1092)
    at org.apache.catalina.startup.HostConfig$DeployDirectory.run(HostConfig.java:1834)
    at java.util.concurrent.Executors$RunnableAdapter.call(Executors.java:511)
    at java.util.concurrent.FutureTask.run(FutureTask.java:266)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(ThreadPoolExecutor.java:1142)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(ThreadPoolExecutor.java:617)
    at java.lang.Thread.run(Thread.java:745)
</code></pre>

<p>After trying several hours I am just wondering how to solve this TAT.</p>