Handler dispatch failed; nested exception is java.lang.AbstractMethodError: Method com/mchange/v2/c3p0/impl/NewProxyResultSet.isClosed()Z is abstract

问题原因：本地用的c3p0为0.9.1.2版本，版本不兼容。

解决方法：

  maven方式：pom引用升级到 c3p0-0.9.5.5，并且加入 mchange-commons-java-0.2.19 的依赖。

  lib方式：直接 下载 c3p0-0.9.5.5.bin.zip，解压后将 c3p0-0.9.5.5lib 下的 c3p0-0.9.5.5.jar 和 mchange-commons-java-0.2.19.jar 导到项目lib目录下。 

具体报错如下：

org.springframework.web.util.NestedServletException: Handler dispatch failed; nested exception is java.lang.AbstractMethodError: Method com/mchange/v2/c3p0/impl/NewProxyResultSet.isClosed()Z is abstract
    org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1055)
    org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:626)
    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:733)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)
根本原因。

java.lang.AbstractMethodError: Method com/mchange/v2/c3p0/impl/NewProxyResultSet.isClosed()Z is abstract
    com.mchange.v2.c3p0.impl.NewProxyResultSet.isClosed(NewProxyResultSet.java)
    org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValuesForSimpleResultMap(DefaultResultSetHandler.java:352)
    org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleRowValues(DefaultResultSetHandler.java:328)
    org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSet(DefaultResultSetHandler.java:301)
    org.apache.ibatis.executor.resultset.DefaultResultSetHandler.handleResultSets(DefaultResultSetHandler.java:194)
    org.apache.ibatis.executor.statement.PreparedStatementHandler.query(PreparedStatementHandler.java:65)
    org.apache.ibatis.executor.statement.RoutingStatementHandler.query(RoutingStatementHandler.java:79)
    org.apache.ibatis.executor.SimpleExecutor.doQuery(SimpleExecutor.java:63)
    org.apache.ibatis.executor.BaseExecutor.queryFromDatabase(BaseExecutor.java:325)
    org.apache.ibatis.executor.BaseExecutor.query(BaseExecutor.java:156)
    org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:109)
    org.apache.ibatis.executor.CachingExecutor.query(CachingExecutor.java:89)
    org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:147)
    org.apache.ibatis.session.defaults.DefaultSqlSession.selectList(DefaultSqlSession.java:140)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:483)
    org.mybatis.spring.SqlSessionTemplate$SqlSessionInterceptor.invoke(SqlSessionTemplate.java:427)
    com.sun.proxy.$Proxy7.selectList(Unknown Source)
    org.mybatis.spring.SqlSessionTemplate.selectList(SqlSessionTemplate.java:224)
    org.apache.ibatis.binding.MapperMethod.executeForMany(MapperMethod.java:147)
    org.apache.ibatis.binding.MapperMethod.execute(MapperMethod.java:80)
    org.apache.ibatis.binding.MapperProxy$PlainMethodInvoker.invoke(MapperProxy.java:152)
    org.apache.ibatis.binding.MapperProxy.invoke(MapperProxy.java:85)
    com.sun.proxy.$Proxy23.selectByExampleWithBLOBs(Unknown Source)
    com.hithere.springmvc.dao.ItemDaoImpl.selectItemsList(ItemDaoImpl.java:22)
    com.hithere.springmvc.controller.ItemController.itemList(ItemController.java:29)
    sun.reflect.NativeMethodAccessorImpl.invoke0(Native Method)
    sun.reflect.NativeMethodAccessorImpl.invoke(NativeMethodAccessorImpl.java:62)
    sun.reflect.DelegatingMethodAccessorImpl.invoke(DelegatingMethodAccessorImpl.java:43)
    java.lang.reflect.Method.invoke(Method.java:483)
    org.springframework.web.method.support.InvocableHandlerMethod.doInvoke(InvocableHandlerMethod.java:190)
    org.springframework.web.method.support.InvocableHandlerMethod.invokeForRequest(InvocableHandlerMethod.java:138)
    org.springframework.web.servlet.mvc.method.annotation.ServletInvocableHandlerMethod.invokeAndHandle(ServletInvocableHandlerMethod.java:106)
    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.invokeHandlerMethod(RequestMappingHandlerAdapter.java:888)
    org.springframework.web.servlet.mvc.method.annotation.RequestMappingHandlerAdapter.handleInternal(RequestMappingHandlerAdapter.java:793)
    org.springframework.web.servlet.mvc.method.AbstractHandlerMethodAdapter.handle(AbstractHandlerMethodAdapter.java:87)
    org.springframework.web.servlet.DispatcherServlet.doDispatch(DispatcherServlet.java:1040)
    org.springframework.web.servlet.DispatcherServlet.doService(DispatcherServlet.java:943)
    org.springframework.web.servlet.FrameworkServlet.processRequest(FrameworkServlet.java:1006)
    org.springframework.web.servlet.FrameworkServlet.doGet(FrameworkServlet.java:898)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:626)
    org.springframework.web.servlet.FrameworkServlet.service(FrameworkServlet.java:883)
    javax.servlet.http.HttpServlet.service(HttpServlet.java:733)
    org.apache.tomcat.websocket.server.WsFilter.doFilter(WsFilter.java:53)