JNDI ClassCastException [英] JNDI ClassCastException

问题描述

我正在尝试将JNDI与名为CEDataSource的自定义数据源一起使用.根据我的理解，我还必须创建一个自定义工厂.

I am attempting to use JNDI with a custom DataSource called CEDataSource. From my understanding for this to work I would have to create a custom factory as well.

所以我创建了一个自定义工厂，该工厂将返回CEDataSource对象，但是现在当我尝试在Java中使用此对象时

So I created a custom factory that would return the CEDataSource object but now when I attempt to use this in Java with

Context initCtx = new InitialContext();
Context envCtx = (Context) initCtx.lookup("java:comp/env");
// Look up our data source
   CEDataSource ds = (CEDataSource)envCtx.lookup("jdbc/cePu");

我收到异常ClassCastException "CEDataSource无法映射到CEDataSource".我将CEDataSource和CEDataSourceFactory添加到TOMCAT/lib文件夹中，并在已部署的应用程序中引用了这个jar.

I get the exception ClassCastException "CEDataSource cannot be mapped to CEDataSource". I added the CEDataSource and the CEDataSourceFactory to the TOMCAT/lib folder as well as referenced this same jar on my deployed application.

对于为什么会出现此错误的任何帮助，将不胜感激.谢谢

Any help would be greatly appreciated on why this possible error may occur. Thanks

推荐答案

"CEDataSource无法映射到CEDataSource"似乎是指两个地方的CEDataSource都不相同.

"CEDataSource cannot be mapped to CEDataSource" seems to point to the fact that it's not the same "CEDataSource" in both places.

类加载器可能有所不同，如果在多个位置具有相同的jars/.class，通常会发生这种情况.

What could be different is the classloader and this usually happens if you have the same jars/.class(es) in multiple locations.

您有多个jar副本吗? 尝试在共享的tomcat lib中创建一个副本，以便无论您从何处访问它，都由同一个类加载器加载.

Do you have multiple copies of your jar? Try to have a single copy, maybe in the shared tomcat lib so it's loaded by the same classloader no matter from where you access it from.

这篇关于JNDI ClassCastException的文章就介绍到这了，希望我们推荐的答案对大家有所帮助，也希望大家多多支持IT屋！