Question

关于java httpclient编程的问题

import java.io.FileOutputStream;
import java.io.InputStream;
import java.io.OutputStream;
import org.apache.commons.httpclient.HttpClient;
import org.apache.commons.httpclient.HttpStatus;
import org.apache.commons.httpclient.methods.GetMethod;

public class spider {

public static void main(String[] args) {
HttpClient hp = new HttpClient();
}
}
很简单的程序但是编译出这样的结果：
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/commons/httpclient/HttpClient
at s.sb.main(sb.java:18)
Caused by: java.lang.ClassNotFoundException: org.apache.commons.httpclient.HttpClient
at java.net.URLClassLoader$1.run(URLClassLoader.java:202)
at java.security.AccessController.doPrivileged(Native Method)
at java.net.URLClassLoader.findClass(URLClassLoader.java:190)
at java.lang.ClassLoader.loadClass(ClassLoader.java:306)
at sun.misc.Launcher$AppClassLoader.loadClass(Launcher.java:301)
at java.lang.ClassLoader.loadClass(ClassLoader.java:247)
... 1 more
已经引入了所需的三个jar包，是要设置环境变量吗

Answer 1

请查查是否没有正确地导入jar包. 在您的webroot目录下webinf下放置一个lib文件夹,三个包加入其中,右键lib --build path.

Answer 2

引入的三个包在path下(编译器右键工程-属性-BuildPath)可以看到吗，发个截图看看吧