HttpClient

Posted 2020-08-13 幽人月

　　最近写了些接口，使用到了HttpClient，这里留作复习

　　HttpClient有新旧之分org.apache.commons.httpclient.HttpClient和org.apache.http.client.HttpClient

　　org.apache.http.client.HttpClient 取代了org.apache.commons.httpclient.HttpClient

　　这里就不探讨org.apache.commons.httpclient.HttpClient的用法了。

　　首先是get方法

　　

public static void get(){
        /**
         * org.apache.commons.httpclient.HttpClient还是class
         * org.apache.http.client.HttpClient已经是interface了
         */
        CloseableHttpClient httpclient = HttpClients.createDefault();
        try {
            // 创建httpget.    
            HttpGet httpget = new HttpGet("http://localhost:8080/test/MyTestServlet?paramter=111");
            System.out.println("executing request " + httpget.getURI());
            // 执行get请求.    
            //要是不加httpcore-4.4.4.jar这边编译不过去，有空看看
            CloseableHttpResponse response = httpclient.execute(httpget);
            // 获取响应实体    
            HttpEntity entity = response.getEntity();
            System.out.println("--------------------------------------");  
            // 打印响应状态    
            System.out.println(response.getStatusLine());
            if (entity != null) {  
                // 打印响应内容长度    
                System.out.println("Response content length: " + entity.getContentLength());  
                // 打印响应内容    
                System.out.println("Response content: " + EntityUtils.toString(entity));  
            }  
            System.out.println("------------------------------------"); 
            
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally{
            try {
                httpclient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }  
        }
    }

　　普通的post请求

public static void commonPost(){
        // 创建默认的httpClient实例. 
        CloseableHttpClient httpClient = HttpClients.createDefault();
        // 创建httppost    
        HttpPost httppost = new HttpPost("http://localhost:8080/test/MyTestServlet");
        // 创建参数队列    
        List<NameValuePair> formparams = new ArrayList<NameValuePair>();  
        formparams.add(new BasicNameValuePair("paramter", "hou12312se"));
        UrlEncodedFormEntity uefEntity;  
        try {
            uefEntity = new UrlEncodedFormEntity(formparams, "UTF-8");
            httppost.setEntity(uefEntity);  
            System.out.println("executing request " + httppost.getURI());  
            CloseableHttpResponse response = httpClient.execute(httppost);
            HttpEntity entity = response.getEntity();  
            if (entity != null) {  
                System.out.println("--------------------------------------");  
                System.out.println("Response content: " + EntityUtils.toString(entity, "UTF-8"));  
                System.out.println("--------------------------------------");  
            } 
        } catch (UnsupportedEncodingException e) {
            e.printStackTrace();
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        } finally {
            try {
                httpClient.close();
            } catch (IOException e) {
                e.printStackTrace();
            }  
        }
        
    }

View Code

　　Content-Type为application/x-www-form-urlencoded的post请求

public static void specialPost(){
        CloseableHttpClient httpClient = HttpClients.createDefault();
        HttpPost httpPost = new HttpPost("http://localhost:8081/test/doPostTestServlet");
        List<NameValuePair> list = new ArrayList<NameValuePair>();
        list.add(new BasicNameValuePair("UserNumber", "13173001830"));
        list.add(new BasicNameValuePair("corp_id", "qd007"));
        httpPost.setHeader("Content-Type", "application/x-www-form-urlencoded");
        try {
            UrlEncodedFormEntity urlEncodedFormEntity = new UrlEncodedFormEntity(list);
            httpPost.setEntity(urlEncodedFormEntity);
            CloseableHttpResponse response = httpClient.execute(httpPost);
            HttpEntity entity = response.getEntity(); 
            System.out.println(EntityUtils.toString(entity, "utf-8"));
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

　　Content-Type为application/json的post请求

public static void specialPost1(){
        CloseableHttpClient httpClient = HttpClients.createDefault();
        HttpPost httpPost = new HttpPost("http://localhost:8081/test/doPostTestServlet");
        JSONObject jsonObject = new JSONObject();
        jsonObject.put("name", "vincent");
        jsonObject.put("age", "24");//换成int型的有区别吗？
        jsonObject.put("height", "182");
        System.out.println("jsonObject大小:" + jsonObject.size());
        httpPost.setHeader("Content-Type", "application/json");
        StringEntity entity = new StringEntity(jsonObject.toString(), "utf-8");
        httpPost.setEntity(entity);
        try {
            CloseableHttpResponse response = httpClient.execute(httpPost);
            HttpEntity httpEntity = response.getEntity();
            System.out.println(EntityUtils.toString(httpEntity, "utf-8"));
        } catch (ClientProtocolException e) {
            e.printStackTrace();
        } catch (IOException e) {
            e.printStackTrace();
        }
    }

View Code

这里有2种方式