Cannot instantiate the type HttpClient問題

看本身動手寫爬蟲，沒想到一上來就跪了。

裏面提到用的jar包是apache的http客戶端開源項目---HttpClient

就去官網下載了一個版本4.3

當按書上代碼敲時

HttpClient httpclient = new HttpClient();

敲完這句，就給跪了

提示Cannot instantiate the type HttpClient，

google 了下，在stackoverflow上面說是應該

HttpClient httpclient = new DefaultHttpClient();

這樣寫，不過得先import org.apache.http.impl.client.DefaultHttpClient;

試了一下。。。果真能夠，可是後面的GetMethod啥的都有，

最後才特麼發現從4.×版本後，它的用法就變了不能這麼使用了

給個官網示例看看就知道咋回事了

package spider;

import java.io.IOException;

import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.ResponseHandler;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.util.EntityUtils;

public class Spider {
    public static void main(String[] args) throws Exception{
        CloseableHttpClient httpclient = HttpClients.createDefault();
        try{
            String url = "http://www.baidu.com";
            HttpGet httpGet = new HttpGet(url);
            System.out.println("executing request " + httpGet.getURI());
            
            ResponseHandler<String> responseHandler = new ResponseHandler<String>(){
                public String handleResponse(final HttpResponse response) throws ClientProtocolException,IOException{
                    int status = response.getStatusLine().getStatusCode();
                    if (status >= 200 && status < 300){
                        HttpEntity entity = response.getEntity();
                        return entity !=null ? EntityUtils.toString(entity) : null;
                    }else{
                        throw new ClientProtocolException("Unexpected response status: " + status);
                    }
                }
            };
            String responseBody = httpclient.execute(httpGet,responseHandler);
            System.out.println("-------------------------------------------");
            System.out.println(responseBody);
            System.out.println("-------------------------------------------");
        }finally{
            httpclient.close();
        }
    }
}