一、HttpClient1、pom依赖
<!--HttpClient--><dependency> <groupId>commons-httpclient</groupId> <artifactId>commons-httpclient</artifactId> <version>3.1</version></dependency>
2、HttpClient代码实现
public class HttpClientUtil { /** * httpClient的get请求方式 * 使用GetMethod来访问一个URL对应的网页实现步骤： * 1.生成一个HttpClient对象并设置相应的参数； * 2.生成一个GetMethod对象并设置响应的参数； * 3.用HttpClient生成的对象来执行GetMethod生成的Get方法； * 4.处理响应状态码； * 5.若响应正常，处理HTTP响应内容； * 6.释放连接。 * @param url * @param charset * @return */ public static String doGet(String url, String charset) { //1.生成HttpClient对象并设置参数 HttpClient httpClient = new HttpClient(); //设置Http连接超时为5秒 httpClient.getHttpConnectionManager().getParams().setConnectionTimeout(5000); //2.生成GetMethod对象并设置参数 GetMethod getMethod = new GetMethod(url); //设置get请求超时为5秒 getMethod.getParams().setParameter(HttpMethodParams.SO_TIMEOUT, 5000); //设置请求重试处理，用的是默认的重试处理：请求三次 getMethod.getParams().setParameter(HttpMethodParams.RETRY_HANDLER, new DefaultHttpMethodRetryHandler()); String response = ""; //3.执行HTTP GET 请求 try { int statusCode = httpClient.executeMethod(getMethod); //4.判断访问的状态码 if (statusCode != HttpStatus.SC_OK) { System.err.println("请求出错：" + getMethod.getStatusLine()); } //5.处理HTTP响应内容 //HTTP响应头部信息，这里简单打印 Header[] headers = getMethod.getResponseHeaders(); for(Header h : headers) { System.out.println(h.getName() + "---------------" + h.getValue()); } //读取HTTP响应内容，这里简单打印网页内容 //读取为字节数组 byte[] responseBody = getMethod.getResponseBody(); response = new String(responseBody, charset); System.out.println("-----------response:" + response); //读取为InputStream，在网页内容数据量大时候推荐使用 //InputStream response = getMethod.getResponseBodyAsStream(); } catch (HttpException e) { //发生致命的异常，可能是协议不对或者返回的内容有问题 System.out.println("请检查输入的URL!"); e.printStackTrace(); } catch (IOException e) { //发生网络异常 System.out.println("发生网络异常!"); } finally { //6.释放连接 getMethod.releaseConnection(); } return response; } /** * post请求 * @param url * @param json * @return */ public static String doPost(String url, JSONObject json){ HttpClient httpClient = new HttpClient(); PostMethod postMethod = new PostMethod(url); postMethod.addRequestHeader("accept", "*/*"); postMethod.addRequestHeader("connection", "Keep-Alive"); //设置json格式传送 postMethod.addRequestHeader("Content-Type", "application/json;charset=GBK"); //必须设置下面这个Header postMethod.addRequestHeader("User-Agent", "Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/58.0.3029.81 Safari/537.36"); //添加请求参数 postMethod.addParameter("commentId", json.getString("commentId")); String res = ""; try { int code = httpClient.executeMethod(postMethod); if (code == 200){ res = postMethod.getResponseBodyAsString(); System.out.println(res); } } catch (IOException e) { e.printStackTrace(); } return res; } public static void main(String[] args) { System.out.println(doGet("http://tcc.taobao.com/cc/json/mobile_tel_segment.htm?tel=13026194071", "GBK")); System.out.println("-----------分割线------------"); System.out.println("-----------分割线------------"); System.out.println("-----------分割线------------"); JSONObject jsonObject = new JSONObject(); jsonObject.put("commentId", "13026194071"); System.out.println(doPost("http://tcc.taobao.com/cc/json/mobile_tel_segment.htm?tel=13026194071", jsonObject)); }}
3、建议
代码复杂，还得操心资源回收等。代码很复杂，冗余代码多，不建议直接使用。
二、okhttp1、简介
OkHttp是一个高效的HTTP客户端，允许所有同一个主机地址的请求共享同一个socket连接；连接池减少请求延时；透明的GZIP压缩减少响应数据的大小；缓存响应内容，避免一些完全重复的请求
当网络出现问题的时候OkHttp依然坚守自己的职责，它会自动恢复一般的连接问题，如果你的服务有多个IP地址，当第一个IP请求失败时，OkHttp会交替尝试你配置的其他IP，OkHttp使用现代TLS技术(SNI, ALPN)初始化新的连接，当握手失败时会回退到TLS 1.0。
2、pom依赖
<dependency> <groupId>com.squareup.okhttp3</groupId> <artifactId>okhttp</artifactId> <version>3.10.0</version></dependency>
它的请求/响应 API 使用构造器模式builders来设计，它支持阻塞式的同步请求和带回调的异步请求。
3、配置文件
@Configurationpublic class OkHttpConfig { @Bean public OkHttpClient okHttpClient() { return new OkHttpClient.Builder() //.sslSocketFactory(sslSocketFactory(), x509TrustManager()) .retryOnConnectionFailure(false) .connectionPool(pool()) .connectTimeout(30, TimeUnit.SECONDS) .readTimeout(30, TimeUnit.SECONDS) .writeTimeout(30,TimeUnit.SECONDS) .build(); } @Bean public X509TrustManager x509TrustManager() { return new X509TrustManager() { @Override public void checkClientTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException { } @Override public void checkServerTrusted(X509Certificate[] x509Certificates, String s) throws CertificateException { } @Override public X509Certificate[] getAcceptedIssuers() { return new X509Certificate[0]; } }; } @Bean public SSLSocketFactory sslSocketFactory() { try { //信任任何链接 SSLContext sslContext = SSLContext.getInstance("TLS"); sslContext.init(null, new TrustManager[]{x509TrustManager()}, new SecureRandom()); return sslContext.getSocketFactory(); } catch (NoSuchAlgorithmException e) { e.printStackTrace(); } catch (KeyManagementException e) { e.printStackTrace(); } return null; } /** * Create a new connection pool with tuning parameters appropriate for a single-user application. * The tuning parameters in this pool are subject to change in future OkHttp releases. Currently */ @Bean public ConnectionPool pool() { return new ConnectionPool(200, 5, TimeUnit.MINUTES); }}
4、客户端工具
@Slf4jpublic class OkHttpClient { private static final MediaType JSON = MediaType.parse("application/json; charset=utf-8"); private volatile static okhttp3.OkHttpClient client; private static final int MAX_IDLE_CONNECTION = Integer .parseInt(ConfigManager.get("httpclient.max_idle_connection")); private static final long KEEP_ALIVE_DURATION = Long .parseLong(ConfigManager.get("httpclient.keep_alive_duration")); private static final long CONNECT_TIMEOUT = Long.parseLong(ConfigManager.get("httpclient.connectTimeout")); private static final long READ_TIMEOUT = Long.parseLong(ConfigManager.get("httpclient. ")); /** * 单例模式(双重检查模式) 获取类实例 * * @return client */ private static okhttp3.OkHttpClient getInstance() { if (client == null) { synchronized (okhttp3.OkHttpClient.class) { if (client == null) { client = new okhttp3.OkHttpClient.Builder() .connectTimeout(CONNECT_TIMEOUT, TimeUnit.SECONDS) .readTimeout(READ_TIMEOUT, TimeUnit.SECONDS) .connectionPool(new ConnectionPool(MAX_IDLE_CONNECTION, KEEP_ALIVE_DURATION, TimeUnit.MINUTES)) .build(); } } } return client; } public static String syncPost(String url, String json) throws IOException { RequestBody body = RequestBody.create(JSON, json); Request request = new Request.Builder() .url(url) .post(body) .build(); try { Response response = OkHttpClient.getInstance().newCall(request).execute(); if (response.isSuccessful()) { String result = response.body().string(); log.info("syncPost response = {}, responseBody= {}", response, result); return result; } String result = response.body().string(); log.info("syncPost response = {}, responseBody= {}", response, result); throw new IOException("三方接口返回http状态码为" + response.code()); } catch (Exception e) { log.error("syncPost() url:{} have a ecxeption {}", url, e); throw new RuntimeException("syncPost() have a ecxeption {}" + e.getMessage()); } } public static String syncGet(String url, Map<String, Object> headParamsMap) throws IOException { Request request; final Request.Builder builder = new Request.Builder().url(url); try { if (!CollectionUtils.isEmpty(headParamsMap)) { final Iterator<Map.Entry<String, Object>> iterator = headParamsMap.entrySet() .iterator(); while (iterator.hasNext()) { final Map.Entry<String, Object> entry = iterator.next(); builder.addHeader(entry.getKey(), (String) entry.getValue()); } } request = builder.build(); Response response = OkHttpClient.getInstance().newCall(request).execute(); String result = response.body().string(); log.info("syncGet response = {},responseBody= {}", response, result); if (!response.isSuccessful()) { throw new IOException("三方接口返回http状态码为" + response.code()); } return result; } catch (Exception e) { log.error("remote interface url:{} have a ecxeption {}", url, e); throw new RuntimeException("三方接口返回异常"); } }}
三、RestTemplate1、pom依赖
<dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId></dependency>
2、get请求（不带参的即把参数取消即可）
// 1-getForObject()User user1 = this.restTemplate.getForObject(uri, User.class);// 2-getForEntity()ResponseEntity<User> responseEntity1 = this.restTemplate.getForEntity(uri, User.class);HttpStatus statusCode = responseEntity1.getStatusCode();HttpHeaders header = responseEntity1.getHeaders();User user2 = responseEntity1.getBody(); // 3-exchange()RequestEntity requestEntity = RequestEntity.get(new URI(uri)).build();ResponseEntity<User> responseEntity2 = this.restTemplate.exchange(requestEntity, User.class);User user3 = responseEntity2.getBody();
方式一：
Notice notice = restTemplate.getForObject("http://fantj.top/notice/list/{1}/{2}" , Notice.class,1,5);
方式二：
Map<String,String> map = new HashMap();map.put("start","1");map.put("page","5");Notice notice = restTemplate.getForObject("http://fantj.top/notice/list/" , Notice.class,map);
3、post请求
// 1-postForObject()User user1 = this.restTemplate.postForObject(uri, user, User.class);// 2-postForEntity()ResponseEntity<User> responseEntity1 = this.restTemplate.postForEntity(uri, user, User.class);// 3-exchange()RequestEntity<User> requestEntity = RequestEntity.post(new URI(uri)).body(user);ResponseEntity<User> responseEntity2 = this.restTemplate.exchange(requestEntity, User.class);
方式一：
String url = "http://demo/api/book/";HttpHeaders headers = new HttpHeaders();MediaType type = MediaType.parseMediaType("application/json; charset=UTF-8");headers.setContentType(type);String requestJson = "{...}";HttpEntity<String> entity = new HttpEntity<String>(requestJson,headers);String result = restTemplate.postForObject(url, entity, String.class);System.out.println(result);
方式二：
@Testpublic void rtPostObject(){ RestTemplate restTemplate = new RestTemplate(); String url = "http://47.xxx.xxx.96/register/checkEmail"; HttpHeaders headers = new HttpHeaders(); headers.setContentType(MediaType.APPLICATION_FORM_URLENCODED); MultiValueMap<String, String> map= new LinkedMultiValueMap<>(); map.add("email", "844072586@qq.com"); HttpEntity<MultiValueMap<String, String>> request = new HttpEntity<>(map, headers); ResponseEntity<String> response = restTemplate.postForEntity( url, request , String.class ); System.out.println(response.getBody());}
使用RestTemplate需注意：
使用RestTemplate发送请求，当请求体是String时，应这样配置：
RestTemplate restTemplate = new RestTemplate(factory); restTemplate .getMessageConverters() .set(1, new StringHttpMessageConverter(StandardCharsets.UTF_8));
如果没有自定义StringHttpMessageConverter，默认的StringHttpMessageConverter使用的字符集是ISO_8859_1，当请求体包含中文时，会乱码。
以上为个人经验，希望能给大家一个参考，也希望大家多多支持。
心中有愿望一定要去闯，努力实现最初的梦想，
