急！！！！求大侠指点，请问这是什么错误，在线等...
ype Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
javax.servlet.ServletException: Servlet execution threw an exception
root cause
java.lang.NoClassDefFoundError: org/logicalcobwebs/proxool/ProxoolException
java.lang.Class.getDeclaredConstructors0(Native Method)
java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
java.lang.Class.getConstructor0(Class.java:2699)
java.lang.Class.newInstance0(Class.java:326)
java.lang.Class.newInstance(Class.java:308)
org.hibernate.connection.ConnectionProviderFactory.newConnectionProvider(ConnectionProviderFactory.java:96)
org.hibernate.connection.ConnectionProviderFactory.newConnectionProvider(ConnectionProviderFactory.java:79)
org.hibernate.cfg.SettingsFactory.createConnectionProvider(SettingsFactory.java:448)
org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:89)
org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2101)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1325)
com.hoteam.kaide.abc.dao.HibernateUtils.<clinit>(HibernateUtils.java:16)
com.hoteam.kaide.abc.dao.AbcTestDAO.save(AbcTestDAO.java:33)
com.hoteam.kaide.abc.service.AbcService.addAbc(AbcService.java:14)
com.hoteam.kaide.abc.action.AbcAction.execute(AbcAction.java:35)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
root cause
java.lang.ClassNotFoundException: org.logicalcobwebs.proxool.ProxoolException
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1363)
org.apache.catalina.loader.WebappClassLoader.loadClass(WebappClassLoader.java:1209)
java.lang.ClassLoader.loadClassInternal(ClassLoader.java:320)
java.lang.Class.getDeclaredConstructors0(Native Method)
java.lang.Class.privateGetDeclaredConstructors(Class.java:2389)
java.lang.Class.getConstructor0(Class.java:2699)
java.lang.Class.newInstance0(Class.java:326)
java.lang.Class.newInstance(Class.java:308)
org.hibernate.connection.ConnectionProviderFactory.newConnectionProvider(ConnectionProviderFactory.java:96)
org.hibernate.connection.ConnectionProviderFactory.newConnectionProvider(ConnectionProviderFactory.java:79)
org.hibernate.cfg.SettingsFactory.createConnectionProvider(SettingsFactory.java:448)
org.hibernate.cfg.SettingsFactory.buildSettings(SettingsFactory.java:89)
org.hibernate.cfg.Configuration.buildSettings(Configuration.java:2101)
org.hibernate.cfg.Configuration.buildSessionFactory(Configuration.java:1325)
com.hoteam.kaide.abc.dao.HibernateUtils.<clinit>(HibernateUtils.java:16)
com.hoteam.kaide.abc.dao.AbcTestDAO.save(AbcTestDAO.java:33)
com.hoteam.kaide.abc.service.AbcService.addAbc(AbcService.java:14)
com.hoteam.kaide.abc.action.AbcAction.execute(AbcAction.java:35)
org.apache.struts.action.RequestProcessor.processActionPerform(RequestProcessor.java:431)
org.apache.struts.action.RequestProcessor.process(RequestProcessor.java:236)
org.apache.struts.action.ActionServlet.process(ActionServlet.java:1196)
org.apache.struts.action.ActionServlet.doGet(ActionServlet.java:414)
javax.servlet.http.HttpServlet.service(HttpServlet.java:690)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
note The full stack trace of the root cause is available in the Apache Tomcat/5.5.26 logs.
------解决方案--------------------
关于最常用的数据库连接池，proxool，注意其版本，0.9.1版本是需要两个jar包的(proxool-0.9.1.jar和proxool-cglib.jar)，只有proxool-0.9.1.jar会报NoClassDefFoundError: org/logicalcobwebs/cglib/core/NamingPolicy错误，但是有些proxool版本是不会的，比如proxool-0.8.3.jar就不会报这个错，原因就是proxool-0.8.3.jar里面有org/logicalcobwebs/cglib/core/NamingPolicy这个类，但是proxool-0.9.1.jar没有这个类，新的版本重新组织了jar包，在proxool-0.9.1.jar里去掉了一些包结构，移动到了proxool-cglib.jar这个jar包里头。当然proxool-cglib.jar这个jar包还增加了其他的类(不单止是把proxool-0.9.1.jar的缺失的移到proxool-0.8.3.jar，要不然这个干没有意思)
java.io.CharConversionException: Not an ISO 8859-1 character这个错误呢，是配置好web.xml之后，想要访问proxool的管理员界面的时候，在输入了在tomcat-users.xml配置的用户名和密码后爆出来的错误。解决办法其实就是proxool的版本问题，我用的proxool-0.8.3.jar就报错了，但是换成proxool-0.9.1.jar和proxool-cglib.jar之后就好了！！
[解决办法]
连接池的问题
[解决办法]
