Question

我的程序包含以下行，并且此时挂起，我不太清楚为什么。

PoolingHttpClientConnectionManager connectionManager = new PoolingHttpClientConnectionManager();

在Eclipse中调试时，如果我在Display视图中尝试评估“new PoolingHttpClientConnectionManager（）”，我会收到以下错误：

java.lang.NoClassDefFoundError: org/apache/http/config/Lookup
    at java.lang.Class.forName0(Native Method)
    at java.lang.Class.forName(Unknown Source)
    ...omitted - referring to specific lines in code...
    at java.util.concurrent.FutureTask$Sync.innerRun(Unknown Source)
    at java.util.concurrent.FutureTask.run(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor.runWorker(Unknown Source)
    at java.util.concurrent.ThreadPoolExecutor$Worker.run(Unknown Source)
    at java.lang.Thread.run(Unknown Source)
Caused by: java.lang.ClassNotFoundException: org.apache.http.config.Lookup
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.net.URLClassLoader$1.run(Unknown Source)
    at java.security.AccessController.doPrivileged(Native Method)
    at java.net.URLClassLoader.findClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    at sun.misc.Launcher$AppClassLoader.loadClass(Unknown Source)
    at java.lang.ClassLoader.loadClass(Unknown Source)
    ... 10 more

我正在使用org.apache.httpcomponents中的httpclient.jar版本4.3.1。

其他人遇到过这个问题？有解决方案吗或者我在做些傻事？

Answer 1

你还有httpcore罐子吗？（4.3版本）我在那里找到了课程。

Answer 2

org.apache.http.config。查找类不在httpclient-4.3.1.jar中。它位于httpcore-4.3.jar。

如果您不使用Maven，要了解httpclient依赖关系，请参阅http://hc.apache.org/httpcomponents-client-4.3.x/httpclient/dependencies.html

Answer 3

也许您忘了包含/下载HttpCore

http://hc.apache.org/downloads.cgi

无法创建新的PoolingHttpClientConnectionManager

3 个答案: