Java发送GET、POST请求代码详解编程语言

一、创建一个servlet来接收get或post请求

package guwen; 
 
import java.io.IOException; 
import java.io.InputStream; 
import java.io.PrintWriter; 
 
import javax.servlet.ServletException; 
import javax.servlet.http.HttpServlet; 
import javax.servlet.http.HttpServletRequest; 
import javax.servlet.http.HttpServletResponse; 
 
import org.dom4j.Document; 
import org.dom4j.DocumentException; 
import org.dom4j.io.SAXReader; 
 
public class TestServlet extends HttpServlet{ 
 
    /** 
     * 接收get请求 
     */ 
    @Override 
    protected void doGet(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 
        req.setCharacterEncoding("UTF-8"); 
        resp.setCharacterEncoding("UTF-8"); 
        System.out.println(req.getQueryString());  //打印参数 
        PrintWriter out = resp.getWriter(); 
        out.print("响应");  //响应 
    } 
 
    /** 
     * 接收post请求 
     */ 
    @Override 
    protected void doPost(HttpServletRequest req, HttpServletResponse resp) throws ServletException, IOException { 
        resp.setCharacterEncoding("UTF-8"); 
        req.setCharacterEncoding("UTF-8"); 
        System.out.println(req.getQueryString());  //打印参数 
        InputStream inputStream = req.getInputStream(); 
        SAXReader reader = new SAXReader(); 
        try { 
            Document document = reader.read(inputStream);  //报文体 
            System.out.println(document.asXML()); 
        } catch (DocumentException e) { 
            e.printStackTrace(); 
        } 
        PrintWriter out = resp.getWriter(); 
        out.print("响应");  //响应 
    } 
 
     
}

二、发送请求

package guwen; 
import java.io.IOException; 
import org.apache.http.HttpEntity; 
import org.apache.http.client.ClientProtocolException; 
import org.apache.http.client.config.RequestConfig; 
import org.apache.http.client.methods.CloseableHttpResponse; 
import org.apache.http.client.methods.HttpGet; 
import org.apache.http.client.methods.HttpPost; 
import org.apache.http.entity.StringEntity; 
import org.apache.http.impl.client.CloseableHttpClient; 
import org.apache.http.impl.client.HttpClientBuilder; 
import org.apache.http.util.EntityUtils; 
public class ConnectionUtil { 
     
    public static void main(String[] args) throws ClientProtocolException, IOException { 
        //sent get 
        doGet("http://localhost:8088/sentTest/test?p=123"); 
        //sent post 
        doPost("http://localhost:8088/sentTest/test?p=321","<xml><a>aa</a><b>哈</b></xml>"); 
    } 
     
    /** 
     * 发送get请求 
     * @throws IOException  
     */ 
    public static String doGet(String url) throws ClientProtocolException, IOException { 
         
        CloseableHttpClient httpClient = HttpClientBuilder.create().build();   
         
        HttpGet httpGet = new HttpGet(url);      
   
        //配置请求的超时设置   
        RequestConfig requestConfig = RequestConfig.custom()     
                .setConnectionRequestTimeout(50)   
                .setConnectTimeout(50)     
                .setSocketTimeout(50).build();     
        httpGet.setConfig(requestConfig);    
           
        CloseableHttpResponse response = null; 
        String res = null; 
        try { 
            response = httpClient.execute(httpGet);   //发送请求 
            System.out.println("StatusCode -> " + response.getStatusLine().getStatusCode());   
            HttpEntity entity = response.getEntity();           
            res = EntityUtils.toString(entity,"utf-8");    
            System.out.println(res);   
        } catch (ClientProtocolException e) { 
            throw e; 
        } catch (IOException e) { 
            throw e; 
        } finally{ 
            httpGet.releaseConnection();  
        } 
           
        return res; 
    } 
     
     
     
    /** 
     * 发送get请求 
     * @throws IOException  
     */ 
    public static String doPost(String url,String body) throws IOException { 
         
        CloseableHttpClient httpclient = HttpClientBuilder.create().build();   
        HttpPost httpPost = new HttpPost(url); 
        //配置请求的超时设置   
        RequestConfig requestConfig = RequestConfig.custom()     
                .setConnectionRequestTimeout(50)   
                .setConnectTimeout(50)     
                .setSocketTimeout(50).build();     
        httpPost.setConfig(requestConfig);  
         
        CloseableHttpResponse response = null; 
        String res = null; 
        try { 
            if (body != null) {  //设置报文体 设置编码为 UTF-8 
                StringEntity entity = new StringEntity(body, "UTF-8"); 
                httpPost.setEntity(entity); 
            } 
            response = httpclient.execute(httpPost);  //发送请求 
            System.out.println(response.toString());   
             
            HttpEntity entity = response.getEntity();   
            res = EntityUtils.toString(entity, "utf-8");   
            System.out.println(res);   
        } catch (ClientProtocolException e) { 
            throw e; 
        } catch (IOException e) { 
            throw e; 
        } finally{ 
            httpPost.releaseConnection(); 
        } 
         
        return res; 
         
         
    } 
     
     
}