网络爬虫之httpclient的使用

柔光的暖阳◎ 2022-09-25 05:20 152阅读 0赞

HttpClient 是 Apache Jakarta Common 下的子项目，可以用来提供高效的、最新的、功能丰富的支持 HTTP 协议的客户端编程工具包，并且它支持 HTTP 协议最新的版本和建议。  
如下面java程序，为我写的一个简单的httpclient的测试程序：

package crawlerTest;
    
    import java.io.IOException;
    import org.apache.http.HttpResponse;
    import org.apache.http.HttpStatus;
    import org.apache.http.HttpVersion;
    import org.apache.http.client.HttpClient;
    import org.apache.http.client.methods.HttpGet;
    import org.apache.http.impl.client.DefaultHttpClient;
    import org.apache.http.message.BasicHttpResponse;
    import org.apache.http.util.EntityUtils;
    public class httpTest { 
        public static void main(String[] args) throws IOException {
            HttpClient client = new DefaultHttpClient();   //初始化httpclient
            String personalUrl="http://www.autohome.com.cn/beijing/";     //指定一个种子url
            HttpGet postMethod = new HttpGet(personalUrl);   //post方法请求
            System.out.println("postMethod====="+ postMethod+"=====");
            HttpGet getMethod = new HttpGet(personalUrl);       // get方法请求
            System.out.println("Method======"+getMethod+"=====");
            HttpResponse response = new BasicHttpResponse(HttpVersion.HTTP_1_1,
                    HttpStatus.SC_OK, "OK");                        //初始化response 
            response = client.execute(getMethod);                   //执行响应
            System.out.println("response========"+response+"=====");
            int StatusCode = response.getStatusLine().getStatusCode(); //获取响应状态码
            System.out.println("StatusCode===="+StatusCode+"=====");
            System.out.println(response);
            if(StatusCode == 200){                          //状态码200表示响应成功
                //获取实体内容
                String entity = EntityUtils.toString (response.getEntity(),"utf-8");
                //输出实体内容
                System.out.println(entity);
                EntityUtils.consume(response.getEntity());       //消耗实体
            }else {
                //关闭HttpEntity的流实体
                EntityUtils.consume(response.getEntity());        //消耗实体
            }
        }
    
    }