我正在尝试启动tomcat服务器，但我无法访问网页。
以下是我的日志：
Mar 22, 2015 7:15:53 AM org.apache.catalina.startup.ClassLoaderFactory validateFile
WARNING: Problem with directory [/usr/share/tomcat7/common/classes], exists: [false], isDirectory: [false], canRead: [false]
Mar 22, 2015 7:15:53 AM org.apache.catalina.startup.ClassLoaderFactory validateFile
WARNING: Problem with directory [/usr/share/tomcat7/common], exists: [false], isDirectory: [false], canRead: [false]
Mar 22, 2015 7:15:53 AM org.apache.catalina.startup.ClassLoaderFactory validateFile
WARNING: Problem with directory [/usr/share/tomcat7/server/classes], exists: [false], isDirectory: [false], canRead: [false]
Mar 22, 2015 7:15:53 AM org.apache.catalina.startup.ClassLoaderFactory validateFile
WARNING: Problem with directory [/usr/share/tomcat7/server], exists: [false], isDirectory: [false], canRead: [false]
Mar 22, 2015 7:15:53 AM org.apache.catalina.startup.ClassLoaderFactory validateFile
WARNING: Problem with directory [/usr/share/tomcat7/shared/classes], exists: [false], isDirectory: [false], canRead: [false]
Mar 22, 2015 7:15:53 AM org.apache.catalina.startup.ClassLoaderFactory validateFile
WARNING: Problem with directory [/usr/share/tomcat7/shared], exists: [false], isDirectory: [false], canRead: [false]
Mar 22, 2015 7:15:54 AM org.apache.coyote.AbstractProtocol init
INFO: Initializing ProtocolHandler ["http-bio-8080"]
Mar 22, 2015 7:15:54 AM org.apache.catalina.startup.Catalina load
INFO: Initialization processed in 1522 ms
Mar 22, 2015 7:15:54 AM org.apache.catalina.core.StandardService startInternal
INFO: Starting service Catalina
Mar 22, 2015 7:15:54 AM org.apache.catalina.core.StandardEngine startInternal
INFO: Starting Servlet Engine: Apache Tomcat/7.0.52 (Ubuntu)
Mar 22, 2015 7:15:54 AM org.apache.catalina.startup.HostConfig deployDirectory
INFO: Deploying web application directory /var/lib/tomcat7/webapps/ROOT
你能给我一条解决问题的途径吗？