webmagic程序noclassdeffounderror classnotfoundexception

public class GithubRepoPageProcessor implements PageProcessor {
// 抓取网站的相关配置，包括编码、抓取间隔、重试次数等
private Site site = Site.me().setRetryTimes(3).setSleepTime(100);
private static int count =0;

    public Site getSite() {
        return site;
    }

    public void process(Page page) {
        //判断链接是否符合http://www.cnblogs.com/任意个数字字母-/p/7个数字.html格式
        if(!page.getUrl().regex("http://www.cnblogs.com/[a-z 0-9 -]+/p/[0-9]{7}.html").match()){
            //加入满足条件的链接
            page.addTargetRequests(
                    page.getHtml().xpath("//*[@id=\"post_list\"]/div/div[@class='post_item_body']/h3/a/@href").all());
        }else{
            //获取页面需要的内容
            System.out.println("抓取的内容："+
                    page.getHtml().xpath("//*[@id=\"Header1_HeaderTitle\"]/text()").get()
            );
            count ++;
        }
    }

    public static void main(String[] args) {
        long startTime, endTime;
        System.out.println("开始爬取...");
        startTime = System.currentTimeMillis();
        Spider.create(new GithubRepoPageProcessor()).addUrl("https://www.cnblogs.com/").thread(5).run();
        endTime = System.currentTimeMillis();
        System.out.println("爬取结束，耗时约" + ((endTime - startTime) / 1000) + "秒，抓取了"+count+"条记录");
    }

}

输出结果：
开始爬取...
Exception in thread "main" java.lang.NoClassDefFoundError: org/apache/http/protocol/HttpContext
at us.codecraft.webmagic.Spider.initComponent(Spider.java:280)
at us.codecraft.webmagic.Spider.run(Spider.java:305)
at javaspider.GithubRepoPageProcessor.main(GithubRepoPageProcessor.java:38)
Caused by: java.lang.ClassNotFoundException: org.apache.http.protocol.HttpContext
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)
... 3 more