PermGen space错误解决方法

http://www.cnblogs.com/xwdreamer/archive/2011/11/21/2296930.html

http://blog.csdn.net/fox009/article/details/5633007

http://hi.baidu.com/like_dark/blog/item/19c1948b3292b0799f2fb468.html

http://anyeeye.iteye.com/blog/444624

http://hi.baidu.com/chssheng2007/item/3f8cd7e7d41ed80c8c3ea8c2

http://www.mkyong.com/tomcat/tomcat-javalangoutofmemoryerror-permgen-space/

昨天利用注解整合了一下ssh，去掉了hibernate的配置文件，利用maven管理这个项目的jar包，发现自己一不小心就把不同的版本包给弄进了lib目录里面，导致一直报那些NoClassDefError,只能找到项目的物理lib目录，把所有的jar删除了，让maven再自己加载回来，真是蛋疼啊。（原来是用的maven少，所以不知道maven原来有一个clean命令的）
解决了这个问题，接下来的问题是那个tomcat内存的问题,就是上面那个

-11-21 21:10:46 org.apache.catalina.loader.WebappClassLoader clearReferencesJdbc
严重: The web application [/Application] registered the JDBC driver [com.mysql.jdbc.Driver] but failed to unregister it when the web application was stopped. To prevent a memory leak, the JDBC Driver has been forcibly unregistered.
-11-21 21:10:46 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [/Application] appears to have started a thread named [MySQL Statement Cancellation Timer] but has failed to stop it. This is very likely to create a memory leak.
-11-21 21:10:46 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [/Application] appears to have started a thread named [AWT-Windows] but has failed to stop it. This is very likely to create a memory leak.
-11-21 21:10:46 org.apache.catalina.loader.WebappClassLoader clearReferencesThreads
严重: The web application [/Application] appears to have started a thread named [Thread-14] but has failed to stop it. This is very likely to create a memory leak.
-11-21 21:10:46 org.apache.catalina.loader.WebappClassLoader clearThreadLocalMap
严重: The web application [/Application] created a ThreadLocal with key of type [net.sf.json.AbstractJSON$1] (value [net.sf.json.AbstractJSON$1@3661eeb]) and a value of type [java.util.HashSet] (value [[]]) but failed to remove it when the web application was stopped. This is very likely to create a memory leak.
-11-21 21:10:50 org.apache.catalina.core.ApplicationContext log

而且第一次启动的时候是没有什么报这个错的，在以后的重新部署就会这样了，查了一下，原来是内存不够用了，加载的jar包有点多了