HttpClient的一些用法

一、HttpClient简介

是一个开源的网络请求框架  在Android中是内置

     |--但是：Android5.0之后该框架已经不建议使用了

二、第三方jar包，导包了，下载地址:  http://hc.apache.org/downloads.cgi

三、使用

    1、创建客户端 HttpClient client = new DefaltHttpServlet();

    2、创建请求HttpGet/HttpPost

    3、使用客户端发送请求client.execute(请求)   --返回一个reseponse对象

    4、处理请求的结果

1、简单的代码，初级，中间有失效的方法就不要紧，异常没处理

  

   

    import java.io.BufferedInputStream;
   
   

    import java.io.BufferedOutputStream;
   
   

    import java.io.FileOutputStream;
   
   

     
   
   

    import org.apache.http.HttpEntity;
   
   

    import org.apache.http.HttpResponse;
   
   

    import org.apache.http.client.HttpClient;
   
   

    import org.apache.http.client.methods.HttpGet;
   
   

    import org.apache.http.impl.client.DefaultHttpClient;
   
   

     
   
   

    public class HttpClientDemo01 {
   
   

     
   
   

    	public static void main(String[] args) throws Exception{
   
   

    		HttpClient client = new DefaultHttpClient();
   
   

    		HttpGet get = new HttpGet("https://ss0.baidu.com/7Po3dSag_xI4khGko9WTAnF6hhy/news/q=100/sign=643ba8b7d20735fa97f04ab9ae500f9f/8ad4b31c8701a18b48f518e3982f07082838fe04.jpg");
   
   

    		
   
   

    		HttpResponse response = client.execute(get);
   
   

    		
   
   

    		if (response.getStatusLine().getStatusCode() == 200) {
   
   

    			HttpEntity entity = response.getEntity();
   
   

    			BufferedInputStream bis = new BufferedInputStream(entity.getContent());
   
   

    			
   
   

    			BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("a6.jpg"));
   
   

    			byte[] b = new byte[10240];
   
   

    			int len = 0;
   
   

    			while ((len = bis.read(b)) != -1) {
   
   

    				bos.write(b, 0, len);
   
   

    			}
   
   

    			bos.flush();
   
   

    			bos.close();
   
   

    			bis.close();
   
   

    			
   
   

    		} else {
   
   

    			System.out.println("臣妾做不到啊");
   
   

    		}
   
   

    	
   
   

    	}
   
   

    }
   
  

EntityUtils的使用:

  

   

    import java.io.BufferedOutputStream;
   
   

    import java.io.FileOutputStream;
   
   

     
   
   

    import org.apache.http.HttpEntity;
   
   

    import org.apache.http.HttpResponse;
   
   

    import org.apache.http.client.HttpClient;
   
   

    import org.apache.http.client.methods.HttpGet;
   
   

    import org.apache.http.impl.client.DefaultHttpClient;
   
   

    import org.apache.http.util.EntityUtils;
   
   

     
   
   

    public class HttpClientDemo02 {
   
   

    	public static void main(String[] args) throws Exception{
   
   

    		HttpClient client = new DefaultHttpClient();
   
   

    		
   
   

    		HttpGet get = new HttpGet("https://ss0.baidu.com/7Po3dSag_xI4khGko9WTAnF6hhy/news/q=100/sign=643ba8b7d20735fa97f04ab9ae500f9f/8ad4b31c8701a18b48f518e3982f07082838fe04.jpg");
   
   

    	
   
   

    		HttpResponse responce = client.execute(get);
   
   

    		
   
   

    		if (responce.getStatusLine().getStatusCode() == 200) {
   
   

    			
   
   

    			HttpEntity entity = responce.getEntity();
   
   

    			
   
   

    			BufferedOutputStream bos = new BufferedOutputStream(new FileOutputStream("a7.jpg"));
   
   

    			
   
   

    			//直接用工具转换城byte型数组
   
   

    			bos.write(EntityUtils.toByteArray(entity));
   
   

    			bos.close();
   
   

    		} else {
   
   

    			System.out.println("臣妾做不到啊");
   
   

    		}
   
   

    	}
   
   

    }
   
  

提交表单和EntityUtils的使用：

  

   

    import org.apache.http.HttpEntity;
   
   

    import org.apache.http.HttpResponse;
   
   

    import org.apache.http.NameValuePair;
   
   

    import org.apache.http.client.HttpClient;
   
   

    import org.apache.http.client.entity.UrlEncodedFormEntity;
   
   

    import org.apache.http.client.methods.HttpPost;
   
   

    import org.apache.http.impl.client.DefaultHttpClient;
   
   

    import org.apache.http.message.BasicNameValuePair;
   
   

    import org.apache.http.util.EntityUtils;
   
   

     
   
   

    /**
   
   

     * Entity的工具的使用和表单的提交
   
   

     * @author Mixm
   
   

     * @date 2015年10月8日 下午9:15:51
   
   

     */
   
   

    public class HttpClientDemo03 {
   
   

     
   
   

    	public static void main(String[] args) throws Exception{
   
   

    		HttpClient client = new DefaultHttpClient();
   
   

    		HttpPost post = new HttpPost("http://127.0.0.1:8080/day028_web/LoginServlet");
   
   

    		
   
   

    		//普通表单
   
   

    		NameValuePair name = new BasicNameValuePair("userName", "Mixm");
   
   

    		NameValuePair psw = new BasicNameValuePair("passWord", "0906");
   
   

    		List<NameValuePair> lists = new ArrayList<NameValuePair>();
   
   

    		lists.add(name);
   
   

    		lists.add(psw);
   
   

    		HttpEntity entity = new UrlEncodedFormEntity(lists);
   
   

    		post.setEntity(entity);
   
   

    		
   
   

    		HttpResponse response = client.execute(post);
   
   

    		if (response.getStatusLine().getStatusCode() == 200) {
   
   

    			HttpEntity hEntity = response.getEntity();
   
   

    			System.out.println(EntityUtils.toString(hEntity));
   
   

    		} else {
   
   

    			System.out.println("臣妾做不到啊");
   
   

    		}
   
   

    		
   
   

    	}
   
   

    }
   
  

HttpPost和HttpGet的区别

    如果只是从服务器取数据，就使用HttpGet

    如果要向服务器传数据，就使用HttpPost