应该是连接数据库出现的问题，萌新不懂，跪求大神帮忙解决
HTTP Status 500 -
type Exception report
message
description The server encountered an internal error () that prevented it from fulfilling this request.
exception
java.lang.RuntimeException: java.lang.reflect.InvocationTargetException
cn.itcast.servlet.BaseServlet.service(BaseServlet.java:60)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
cn.itcast.filter.EncodingFilter.doFilter(EncodingFilter.java:30)
root cause
java.lang.reflect.InvocationTargetException
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:597)
cn.itcast.servlet.BaseServlet.service(BaseServlet.java:44)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
cn.itcast.filter.EncodingFilter.doFilter(EncodingFilter.java:30)
root cause
java.lang.RuntimeException: java.sql.SQLException: Connections could not be acquired from the underlying database!
cn.itcast.goods.category.service.CategoryService.findAll(CategoryService.java:89)
cn.itcast.goods.category.web.servlet.CategoryServlet.findAll(CategoryServlet.java:31)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:597)
cn.itcast.servlet.BaseServlet.service(BaseServlet.java:44)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
cn.itcast.filter.EncodingFilter.doFilter(EncodingFilter.java:30)
root cause
java.sql.SQLException: Connections could not be acquired from the underlying database!
com.mchange.v2.sql.SqlUtils.toSQLException(SqlUtils.java:106)
com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:615)
com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:128)
cn.itcast.jdbc.JdbcUtils.getConnection(JdbcUtils.java:43)
cn.itcast.jdbc.TxQueryRunner.query(TxQueryRunner.java:30)
cn.itcast.goods.category.dao.CategoryDao.findAll(CategoryDao.java:69)
cn.itcast.goods.category.service.CategoryService.findAll(CategoryService.java:87)
cn.itcast.goods.category.web.servlet.CategoryServlet.findAll(CategoryServlet.java:31)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:597)
cn.itcast.servlet.BaseServlet.service(BaseServlet.java:44)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
cn.itcast.filter.EncodingFilter.doFilter(EncodingFilter.java:30)
root cause
com.mchange.v2.resourcepool.CannotAcquireResourceException: A ResourcePool could not acquire a resource from its primary factory or source.
com.mchange.v2.resourcepool.BasicResourcePool.awaitAvailable(BasicResourcePool.java:1406)
com.mchange.v2.resourcepool.BasicResourcePool.prelimCheckoutResource(BasicResourcePool.java:594)
com.mchange.v2.resourcepool.BasicResourcePool.checkoutResource(BasicResourcePool.java:514)
com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutAndMarkConnectionInUse(C3P0PooledConnectionPool.java:681)
com.mchange.v2.c3p0.impl.C3P0PooledConnectionPool.checkoutPooledConnection(C3P0PooledConnectionPool.java:608)
com.mchange.v2.c3p0.impl.AbstractPoolBackedDataSource.getConnection(AbstractPoolBackedDataSource.java:128)
cn.itcast.jdbc.JdbcUtils.getConnection(JdbcUtils.java:43)
cn.itcast.jdbc.TxQueryRunner.query(TxQueryRunner.java:30)
cn.itcast.goods.category.dao.CategoryDao.findAll(CategoryDao.java:69)
cn.itcast.goods.category.service.CategoryService.findAll(CategoryService.java:87)
cn.itcast.goods.category.web.servlet.CategoryServlet.findAll(CategoryServlet.java:31)
sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:39)
sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:25)
java.lang.reflect.Method.invoke(Method.java:597)
cn.itcast.servlet.BaseServlet.service(BaseServlet.java:44)
javax.servlet.http.HttpServlet.service(HttpServlet.java:803)
cn.itcast.filter.EncodingFilter.doFilter(EncodingFilter.java:30)
note The full stack trace of the root cause is available in the Apache Tomcat/6.0.13 logs.
