最近在工作中需要在后台调用短信接口,经过研究决定使用HttpClient,自己封装了一个HttpClient工具类,简单轻松的实现get,post,put和delete请求,希望分享给大家。
文章目录
1. 什么是HttpClient
HTTP 协议可能是现在 Internet 上使用得最多、最重要的协议了,越来越多的 Java 应用程序需要直接通过 HTTP 协议来访问网络资源。虽然在 JDK 的 java net包中已经提供了访问 HTTP 协议的基本功能,但是对于大部分应用程序来说,JDK 库本身提供的功能还不够丰富和灵活。HttpClient 是Apache HttpComponents 下的子项目,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。
2. 功能介绍
- 实现了所有 HTTP 的方法(GET,POST,PUT,DELETE 等)
- 支持自动转向
- 支持 HTTPS 协议
- 支持代理服务器等
3. 版本比较
注意本篇博客主要是基于 HttpClient4.5.5 版本的来讲解的,也是现在最新的版本,之所以要提供版本说明的是因为 HttpClient 3 版本和 HttpClient 4 版本差别还是很多大的,基本HttpClient里面的接口都变了,你把 HttpClient 3 版本的代码拿到 HttpClient 4 上面都运行不起来,会报错的。所以一定要注意 HtppClient 的版本问题。
4. HttpClient不能做的事情
HttpClient 不是浏览器,它是一个客户端 HTTP 协议传输类库。HttpClient 被用来发送和接受 HTTP 消息。HttpClient 不会处理 HTTP 消息的内容,不会进行 javascript 解析,不会关心 content type,如果没有明确设置,HttpClient 也不会对请求进行格式化、重定向 url,或者其他任何和 HTTP 消息传输相关的功能。
5. HttpClient使用流程
使用HttpClient发送请求、接收响应很简单,一般需要如下几步即可。
- 创建HttpClient对象。
- 创建请求方法的实例,并指定请求URL。如果需要发送GET请求,创建HttpGet对象;如果需要发送POST请求,创建HttpPost对象。
- 如果需要发送请求参数,可调用HttpGetsetParams方法来添加请求参数;对于HttpPost对象而言,可调用setEntity(HttpEntity entity)方法来设置请求参数。
- 调用HttpClient对象的execute(HttpUriRequest request)发送请求,该方法返回一个HttpResponse对象。
- 调用HttpResponse的getAllHeaders()、getHeaders(String name)等方法可获取服务器的响应头;调用HttpResponse的getEntity()方法可获取HttpEntity对象,该对象包装了服务器的响应内容。程序可通过该对象获取服务器的响应内容。
- 释放连接。无论执行方法是否成功,都必须释放连接
6. HttpClient工具类
本项目采用spring-boot构建,话不多说,上代码
6.1 添加依赖
<properties> <httpclient.version>4.5.5</httpclient.version> <java.version>1.8</java.version> <project.build.sourceEncoding>UTF-8</project.build.sourceEncoding> <project.reporting.outputEncoding>UTF-8</project.reporting.outputEncoding> </properties> <dependencies> <!-- springboot的web和test启动库 --> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-web</artifactId> </dependency> <dependency> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-starter-test</artifactId> </dependency> <!-- apache httpclient组件 --> <dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> </dependency> </dependencies> <build> <finalName>${project.artifactId}</finalName> <plugins> <plugin> <groupId>org.springframework.boot</groupId> <artifactId>spring-boot-maven-plugin</artifactId> </plugin> <!-- 跳过单元测试 --> <plugin> <groupId>org.apache.maven.plugins</groupId> <artifactId>maven-surefire-plugin</artifactId> <configuration> <skipTests>true</skipTests> </configuration> </plugin> </plugins> </build>
6.2 编写spring-boot启动类
/** * Description: springboot启动类 * * @author JourWon * @date Created on 2018年4月19日 */@SpringBootApplicationpublic class Application {public static void main(String[] args) {SpringApplication.run(Application.class, args);}}
6.3 编写get和post请求测试controller
/** * Description: get和post请求测试controller * * @author JourWon * @date Created on 2018年4月19日 */@RestController@RequestMapping("/hello")public class HelloWorldController {@GetMapping("/get")public String get() throws InterruptedException {return "get无参请求成功";}@GetMapping("/getWithParam")public String getWithParam(@RequestParam String message) {return "get带参请求成功,参数message: " + message;}@PostMapping("/post")public String post(@RequestHeader("User-Agent") String userAgent, @RequestHeader("Accept") String accept, @RequestHeader("Accept-Language") String acceptLanguage, @RequestHeader("Accept-Encoding") String acceptEncoding, @RequestHeader("Cookie") String cookie, @RequestHeader("Connection") String conn) {// 打印请求头信息System.out.println("Cookie = " + cookie);System.out.println("Connection = " + conn);System.out.println("Accept = " + accept);System.out.println("Accept-Language = " + acceptLanguage);System.out.println("Accept-Encoding = " + acceptEncoding);System.out.println("User-Agent = " + userAgent);return "post无参请求成功";}@PostMapping("/postWithParam")public String postWithParam(@RequestParam String code, @RequestParam String message) {return "post带参请求成功,参数code: " + code + ",参数message: " + message;}}
6.4 创建httpClient响应结果对象
/** * Description: 封装httpClient响应结果 * * @author JourWon * @date Created on 2018年4月19日 */public class HttpClientResult implements Serializable {/** * 响应状态码 */private int code;/** * 响应数据 */private String content;}
6.5 重点,编写httpclient工具类
/** * Description: httpClient工具类 * * @author JourWon * @date Created on 2018年4月19日 */public class HttpClientUtils {// 编码格式。发送编码格式统一用UTF-8private static final String ENCODING = "UTF-8";// 设置连接超时时间,单位毫秒。private static final int CONNECT_TIMEOUT = 6000;// 请求获取数据的超时时间(即响应时间),单位毫秒。private static final int SOCKET_TIMEOUT = 6000;/** * 发送get请求;不带请求头和请求参数 * * @param url 请求地址 * @return * @throws Exception */public static HttpClientResult doGet(String url) throws Exception {return doGet(url, null, null);}/** * 发送get请求;带请求参数 * * @param url 请求地址 * @param params 请求参数集合 * @return * @throws Exception */public static HttpClientResult doGet(String url, Map<String, String> params) throws Exception {return doGet(url, null, params);}/** * 发送get请求;带请求头和请求参数 * * @param url 请求地址 * @param headers 请求头集合 * @param params 请求参数集合 * @return * @throws Exception */public static HttpClientResult doGet(String url, Map<String, String> headers, Map<String, String> params) throws Exception {// 创建httpClient对象CloseableHttpClient httpClient = HttpClients.createDefault();// 创建访问的地址URIBuilder uriBuilder = new URIBuilder(url);if (params != null) {Set<Entry<String, String>> entrySet = params.entrySet();for (Entry<String, String> entry : entrySet) {uriBuilder.setParameter(entry.getKey(), entry.getValue());}}// 创建http对象HttpGet httpGet = new HttpGet(uriBuilder.build());/** * setConnectTimeout:设置连接超时时间,单位毫秒。 * setConnectionRequestTimeout:设置从connect Manager(连接池)获取Connection * 超时时间,单位毫秒。这个属性是新加的属性,因为目前版本是可以共享连接池的。 * setSocketTimeout:请求获取数据的超时时间(即响应时间),单位毫秒。 如果访问一个接口,多少时间内无法返回数据,就直接放弃此次调用。 */RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(CONNECT_TIMEOUT).setSocketTimeout(SOCKET_TIMEOUT).build();httpGet.setConfig(requestConfig);// 设置请求头packageHeader(headers, httpGet);// 创建httpResponse对象CloseableHttpResponse httpResponse = null;try {// 执行请求并获得响应结果return getHttpClientResult(httpResponse, httpClient, httpGet);} finally {// 释放资源release(httpResponse, httpClient);}}/** * 发送post请求;不带请求头和请求参数 * * @param url 请求地址 * @return * @throws Exception */public static HttpClientResult doPost(String url) throws Exception {return doPost(url, null, null);}/** * 发送post请求;带请求参数 * * @param url 请求地址 * @param params 参数集合 * @return * @throws Exception */public static HttpClientResult doPost(String url, Map<String, String> params) throws Exception {return doPost(url, null, params);}/** * 发送post请求;带请求头和请求参数 * * @param url 请求地址 * @param headers 请求头集合 * @param params 请求参数集合 * @return * @throws Exception */public static HttpClientResult doPost(String url, Map<String, String> headers, Map<String, String> params) throws Exception {// 创建httpClient对象CloseableHttpClient httpClient = HttpClients.createDefault();// 创建http对象HttpPost httpPost = new HttpPost(url);/** * setConnectTimeout:设置连接超时时间,单位毫秒。 * setConnectionRequestTimeout:设置从connect Manager(连接池)获取Connection * 超时时间,单位毫秒。这个属性是新加的属性,因为目前版本是可以共享连接池的。 * setSocketTimeout:请求获取数据的超时时间(即响应时间),单位毫秒。 如果访问一个接口,多少时间内无法返回数据,就直接放弃此次调用。 */RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(CONNECT_TIMEOUT).setSocketTimeout(SOCKET_TIMEOUT).build();httpPost.setConfig(requestConfig);// 设置请求头/*httpPost.setHeader("Cookie", ""); httpPost.setHeader("Connection", "keep-alive"); httpPost.setHeader("Accept", "application/json"); httpPost.setHeader("Accept-Language", "zh-CN,zh;q=0.9"); httpPost.setHeader("Accept-Encoding", "gzip, deflate, br"); httpPost.setHeader("User-Agent", "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36");*/packageHeader(headers, httpPost);// 封装请求参数packageParam(params, httpPost);// 创建httpResponse对象CloseableHttpResponse httpResponse = null;try {// 执行请求并获得响应结果return getHttpClientResult(httpResponse, httpClient, httpPost);} finally {// 释放资源release(httpResponse, httpClient);}}/** * 发送put请求;不带请求参数 * * @param url 请求地址 * @param params 参数集合 * @return * @throws Exception */public static HttpClientResult doPut(String url) throws Exception {return doPut(url);}/** * 发送put请求;带请求参数 * * @param url 请求地址 * @param params 参数集合 * @return * @throws Exception */public static HttpClientResult doPut(String url, Map<String, String> params) throws Exception {CloseableHttpClient httpClient = HttpClients.createDefault();HttpPut httpPut = new HttpPut(url);RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(CONNECT_TIMEOUT).setSocketTimeout(SOCKET_TIMEOUT).build();httpPut.setConfig(requestConfig);packageParam(params, httpPut);CloseableHttpResponse httpResponse = null;try {return getHttpClientResult(httpResponse, httpClient, httpPut);} finally {release(httpResponse, httpClient);}}/** * 发送delete请求;不带请求参数 * * @param url 请求地址 * @param params 参数集合 * @return * @throws Exception */public static HttpClientResult doDelete(String url) throws Exception {CloseableHttpClient httpClient = HttpClients.createDefault();HttpDelete httpDelete = new HttpDelete(url);RequestConfig requestConfig = RequestConfig.custom().setConnectTimeout(CONNECT_TIMEOUT).setSocketTimeout(SOCKET_TIMEOUT).build();httpDelete.setConfig(requestConfig);CloseableHttpResponse httpResponse = null;try {return getHttpClientResult(httpResponse, httpClient, httpDelete);} finally {release(httpResponse, httpClient);}}/** * 发送delete请求;带请求参数 * * @param url 请求地址 * @param params 参数集合 * @return * @throws Exception */public static HttpClientResult doDelete(String url, Map<String, String> params) throws Exception {if (params == null) {params = new HashMap<String, String>();}params.put("_method", "delete");return doPost(url, params);}/** * Description: 封装请求头 * @param params * @param httpMethod */public static void packageHeader(Map<String, String> params, HttpRequestBase httpMethod) {// 封装请求头if (params != null) {Set<Entry<String, String>> entrySet = params.entrySet();for (Entry<String, String> entry : entrySet) {// 设置到请求头到HttpRequestBase对象中httpMethod.setHeader(entry.getKey(), entry.getValue());}}}/** * Description: 封装请求参数 * * @param params * @param httpMethod * @throws UnsupportedEncodingException */public static void packageParam(Map<String, String> params, HttpEntityEnclosingRequestBase httpMethod)throws UnsupportedEncodingException {// 封装请求参数if (params != null) {List<NameValuePair> nvps = new ArrayList<NameValuePair>();Set<Entry<String, String>> entrySet = params.entrySet();for (Entry<String, String> entry : entrySet) {nvps.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));}// 设置到请求的http对象中httpMethod.setEntity(new UrlEncodedFormEntity(nvps, ENCODING));}}/** * Description: 获得响应结果 * * @param httpResponse * @param httpClient * @param httpMethod * @return * @throws Exception */public static HttpClientResult getHttpClientResult(CloseableHttpResponse httpResponse,CloseableHttpClient httpClient, HttpRequestBase httpMethod) throws Exception {// 执行请求httpResponse = httpClient.execute(httpMethod);// 获取返回结果if (httpResponse != null && httpResponse.getStatusLine() != null) {String content = "";if (httpResponse.getEntity() != null) {content = EntityUtils.toString(httpResponse.getEntity(), ENCODING);}return new HttpClientResult(httpResponse.getStatusLine().getStatusCode(), content);}return new HttpClientResult(HttpStatus.SC_INTERNAL_SERVER_ERROR);}/** * Description: 释放资源 * * @param httpResponse * @param httpClient * @throws IOException */public static void release(CloseableHttpResponse httpResponse, CloseableHttpClient httpClient) throws IOException {// 释放资源if (httpResponse != null) {httpResponse.close();}if (httpClient != null) {httpClient.close();}}}
6.6 启动spring-boot,测试get、post请求
/** * Description: HttpClientUtils工具类测试 * * @author JourWon * @date Created on 2018年4月19日 */public class HttpClientUtilsTest {/** * Description: 测试get无参请求 * * @throws Exception */@Testpublic void testGet() throws Exception {HttpClientResult result = HttpClientUtils.doGet("http://127.0.0.1:8080/hello/get");System.out.println(result);}/** * Description: 测试get带参请求 * * @throws Exception */@Testpublic void testGetWithParam() throws Exception {Map<String, String> params = new HashMap<String, String>();params.put("message", "helloworld");HttpClientResult result = HttpClientUtils.doGet("http://127.0.0.1:8080/hello/getWithParam", params);System.out.println(result);}/** * Description: 测试post带请求头不带请求参数 * * @throws Exception */@Testpublic void testPost() throws Exception {Map<String, String> headers = new HashMap<String, String>();headers.put("Cookie", "123");headers.put("Connection", "keep-alive");headers.put("Accept", "application/json");headers.put("Accept-Language", "zh-CN,zh;q=0.9");headers.put("User-Agent", "Mozilla/5.0 (Windows NT 10.0; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/65.0.3325.181 Safari/537.36");HttpClientResult result = HttpClientUtils.doPost("http://127.0.0.1:8080/hello/post", headers, null);System.out.println(result);}/** * Description: 测试post带参请求 * * @throws Exception */@Testpublic void testPostWithParam() throws Exception {Map<String, String> params = new HashMap<String, String>();params.put("code", "0");params.put("message", "helloworld");HttpClientResult result = HttpClientUtils.doPost("http://127.0.0.1:8080/hello/postWithParam", params);System.out.println(result);}}