HttpClient 是 Apache Jakarta Common 下的子项目,可以用来提供高效的、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。
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CloseableHttpClient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,可可调用setEntity(HttpEntity entity)方法来设置请求参数。setParams方法已过时(4.4.1版本)。
- 调用HttpGet、HttpPost对象的setHeader(String name, String value)方法设置header信息,或者调用setHeaders(Header[] headers)设置一组header信息。
- 调用CloseableHttpClient对象的execute(HttpUriRequest request)发送请求,该方法返回一个CloseableHttpResponse。
- 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;调用CloseableHttpResponse的getAllHeaders()、getHeaders(String name)等方法可获取服务器的响应头。
- 释放连接。无论执行方法是否成功,都必须释放连接
具体代码如下(HttpClient-4.4.1):
/** * 简单httpclient实例 * * @author arron * @date 2015年11月11日 下午6:36:49 * @version 1.0 */ public class SimpleHttpClientDemo { /** * 模拟请求 * * @param url 资源地址 * @param map 参数列表 * @param encoding 编码 * @return * @throws ParseException * @throws IOException */ public static String send(String url, Map<String,String> map,String encoding) throws ParseException, IOException{ String body = ""; //创建httpclient对象 CloseableHttpClient client = HttpClients.createDefault(); //创建post方式请求对象 HttpPost httpPost = new HttpPost(url); //装填参数 List<NameValuePair> nvps = new ArrayList<NameValuePair>(); if(map!=null){ for (Entry<String, String> entry : map.entrySet()) { nvps.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } } //设置参数到请求对象中 httpPost.setEntity(new UrlEncodedFormEntity(nvps, encoding)); System.out.println("请求地址:"+url); System.out.println("请求参数:"+nvps.toString()); //设置header信息 //指定报文头【Content-type】、【User-Agent】 httpPost.setHeader("Content-type", "application/x-www-form-urlencoded"); httpPost.setHeader("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)"); //执行请求操作,并拿到结果(同步阻塞) CloseableHttpResponse response = client.execute(httpPost); //获取结果实体 HttpEntity entity = response.getEntity(); if (entity != null) { //按指定编码转换结果实体为String类型 body = EntityUtils.toString(entity, encoding); } EntityUtils.consume(entity); //释放链接 response.close(); return body; } }
对于HTTPS的访问,采取绕过证书的策略:
/** * 绕过验证 * * @return * @throws NoSuchAlgorithmException * @throws KeyManagementException */ public static SSLContext createIgnoreVerifySSL() throws NoSuchAlgorithmException, KeyManagementException { SSLContext sc = SSLContext.getInstance("SSLv3"); // 实现一个X509TrustManager接口,用于绕过验证,不用修改里面的方法 X509TrustManager trustManager = new X509TrustManager() { @Override public void checkClientTrusted( java.security.cert.X509Certificate[] paramArrayOfX509Certificate, String paramString) throws CertificateException { } @Override public void checkServerTrusted( java.security.cert.X509Certificate[] paramArrayOfX509Certificate, String paramString) throws CertificateException { } @Override public java.security.cert.X509Certificate[] getAcceptedIssuers() { return null; } }; sc.init(null, new TrustManager[] { trustManager }, null); return sc; }
然后修改原来的send方法:
/** * 模拟请求 * * @param url 资源地址 * @param map 参数列表 * @param encoding 编码 * @return * @throws NoSuchAlgorithmException * @throws KeyManagementException * @throws IOException * @throws ClientProtocolException */ public static String send(String url, Map<String,String> map,String encoding) throws KeyManagementException, NoSuchAlgorithmException, ClientProtocolException, IOException { String body = ""; //采用绕过验证的方式处理https请求 SSLContext sslcontext = createIgnoreVerifySSL(); // 设置协议http和https对应的处理socket链接工厂的对象 Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create() .register("http", PlainConnectionSocketFactory.INSTANCE) .register("https", new SSLConnectionSocketFactory(sslcontext)) .build(); PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager(socketFactoryRegistry); HttpClients.custom().setConnectionManager(connManager); //创建自定义的httpclient对象 CloseableHttpClient client = HttpClients.custom().setConnectionManager(connManager).build(); // CloseableHttpClient client = HttpClients.createDefault(); //创建post方式请求对象 HttpPost httpPost = new HttpPost(url); //装填参数 List<NameValuePair> nvps = new ArrayList<NameValuePair>(); if(map!=null){ for (Entry<String, String> entry : map.entrySet()) { nvps.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } } //设置参数到请求对象中 httpPost.setEntity(new UrlEncodedFormEntity(nvps, encoding)); System.out.println("请求地址:"+url); System.out.println("请求参数:"+nvps.toString()); //设置header信息 //指定报文头【Content-type】、【User-Agent】 httpPost.setHeader("Content-type", "application/x-www-form-urlencoded"); httpPost.setHeader("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)"); //执行请求操作,并拿到结果(同步阻塞) CloseableHttpResponse response = client.execute(httpPost); //获取结果实体 HttpEntity entity = response.getEntity(); if (entity != null) { //按指定编码转换结果实体为String类型 body = EntityUtils.toString(entity, encoding); } EntityUtils.consume(entity); //释放链接 response.close(); return body; }
但是,如果是自己用jdk或者其他工具生成的证书,还是希望用其他方式认证自签名的证书,这篇文章就来分享一下如何设置信任自签名的证书。当然你也可以参考官网示例中。
要想信任自签名的证书,必须得知道密钥库的路径及密钥库的密码。然后加载到程序来才可以。具体代码如下:
/** * 设置信任自签名证书 * * @param keyStorePath 密钥库路径 * @param keyStorepass 密钥库密码 * @return */ public static SSLContext custom(String keyStorePath, String keyStorepass){ SSLContext sc = null; FileInputStream instream = null; KeyStore trustStore = null; try { trustStore = KeyStore.getInstance(KeyStore.getDefaultType()); instream = new FileInputStream(new File(keyStorePath)); trustStore.load(instream, keyStorepass.toCharArray()); // 相信自己的CA和所有自签名的证书 sc = SSLContexts.custom().loadTrustMaterial(trustStore, new TrustSelfSignedStrategy()).build(); } catch (KeyStoreException | NoSuchAlgorithmException| CertificateException | IOException | KeyManagementException e) { e.printStackTrace(); } finally { try { instream.close(); } catch (IOException e) { } } return sc; }
然后修改原来的send方法:
/** * 模拟请求 * * @param url 资源地址 * @param map 参数列表 * @param encoding 编码 * @return * @throws ParseException * @throws IOException * @throws KeyManagementException * @throws NoSuchAlgorithmException * @throws ClientProtocolException */ public static String send(String url, Map<String,String> map,String encoding) throws ClientProtocolException, IOException { String body = ""; //tomcat是我自己的密钥库的密码,你可以替换成自己的 //如果密码为空,则用"nopassword"代替 SSLContext sslcontext = custom("D:\\keys\\wsriakey", "tomcat"); // 设置协议http和https对应的处理socket链接工厂的对象 Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory>create() .register("http", PlainConnectionSocketFactory.INSTANCE) .register("https", new SSLConnectionSocketFactory(sslcontext)) .build(); PoolingHttpClientConnectionManager connManager = new PoolingHttpClientConnectionManager(socketFactoryRegistry); HttpClients.custom().setConnectionManager(connManager); //创建自定义的httpclient对象 CloseableHttpClient client = HttpClients.custom().setConnectionManager(connManager).build(); // CloseableHttpClient client = HttpClients.createDefault(); //创建post方式请求对象 HttpPost httpPost = new HttpPost(url); //装填参数 List<NameValuePair> nvps = new ArrayList<NameValuePair>(); if(map!=null){ for (Entry<String, String> entry : map.entrySet()) { nvps.add(new BasicNameValuePair(entry.getKey(), entry.getValue())); } } //设置参数到请求对象中 httpPost.setEntity(new UrlEncodedFormEntity(nvps, encoding)); System.out.println("请求地址:"+url); System.out.println("请求参数:"+nvps.toString()); //设置header信息 //指定报文头【Content-type】、【User-Agent】 httpPost.setHeader("Content-type", "application/x-www-form-urlencoded"); httpPost.setHeader("User-Agent", "Mozilla/4.0 (compatible; MSIE 5.0; Windows NT; DigExt)"); //执行请求操作,并拿到结果(同步阻塞) CloseableHttpResponse response = client.execute(httpPost); //获取结果实体 HttpEntity entity = response.getEntity(); if (entity != null) { //按指定编码转换结果实体为String类型 body = EntityUtils.toString(entity, encoding); } EntityUtils.consume(entity); //释放链接 response.close(); return body; }
时间: 2024-10-10 04:23:34