编写不易,转载请注明(http://shihlei.iteye.com/blog/2067688)!
一 概述
HttpClient是最常见的Http请求工具,很好的封装 Http请求,响应,Cookies操作,适合网络爬虫处理静态页面及其他资源。
HttpCient能自动处理302客户端重定向,这个很喜欢!
HttpClient4.3.3 API较之前的版本有不少改变,本文描述请求响应,设置cookies,设置代理等方法。
二 版本
<dependency> <groupId>org.apache.httpcomponents</groupId> <artifactId>httpclient</artifactId> <version>4.3.3</version> </dependency>
三 样例
(1)请求响应
/** * 发送get请求 * * @param url * @throws Exception */ public byte[] sendGetRequest(String url) throws Exception { HttpClient httpClient = HttpClients.createDefault(); HttpGet httpGet = new HttpGet(url); System.out.println("Send Get Request : " + url); return sendRequest(httpClient,httpGet); } /** * 发送post 请求 * * @param request * @throws Exception */ public byte[] sendPostRequest(String url, Map<String, String> params) throws Exception { HttpClient httpClient = HttpClients.createDefault(); HttpPost httpPost = new HttpPost(url); // 设置参数 if (params != null && params.size() > 0) { List<NameValuePair> nvps = new ArrayList<NameValuePair>(); for (Entry<String, String> param : params.entrySet()) { nvps.add(new BasicNameValuePair(param.getKey(), param.getValue())); } httpPost.setEntity(new UrlEncodedFormEntity(nvps)); } System.out.println("Send Post Request : " + url + " , " + params); return sendRequest(httpClient,httpPost); } // 底层请求获得响应数据 private byte[] sendRequest(HttpClient httpClient ,HttpRequestBase request) throws Exception { CloseableHttpResponse response = httpclient.execute(request); // 获取返回的状态列表 StatusLine statusLine = response.getStatusLine(); System.out.println("StatusLine : " + statusLine); if (statusLine.getStatusCode() == HttpStatus.SC_OK) { try { // 获取response entity HttpEntity entity = response.getEntity(); System.out.println("getContentType : " + entity.getContentType().getValue()); System.out.println("getContentEncoding : " + entity.getContentEncoding().getValue()); // 读取响应内容 byte[] responseBody = EntityUtils.toByteArray(entity); // 关闭响应流 EntityUtils.consume(entity); return responseBody; } finally { response.close(); } } return null; }
(2)超时和重定向
在execute前针对Request设置超时的Config
//设置超时 private void setTimeOut(HttpRequestBase request, int timeout) { RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout(timeout) .setConnectTimeout(timeout).setSocketTimeout(timeout).setRedirectsEnabled(true).build(); request.setConfig(requestConfig); }
(3)代理
在创建HttpClient实例的时候,设置代理
//获得设置代理的httpClent实例 private CloseableHttpClient getHttpClientWithProxy(HttpProxy proxy){ HttpHost proxyHost = new HttpHost(proxy.getHost(), proxy.getPort()); CredentialsProvider credentialsProvider = new BasicCredentialsProvider(); credentialsProvider.setCredentials(new AuthScope(proxy.getHost(), proxy.getPort()), new UsernamePasswordCredentials(proxy.getUser(), proxy.getPassword())); return HttpClients.custom().setProxy(proxyHost).setDefaultCredentialsProvider(credentialsProvider) .build(); }
这里有个辅助类:
package x.http.simple; /** * Http代理 * * @author shilei * */ public class HttpProxy { private String proxy = "http"; private String host; private int port; private String user; private String password; public String getProxy() { return proxy; } public void setProxy(String proxy) { this.proxy = proxy; } public String getHost() { return host; } public void setHost(String host) { this.host = host; } public int getPort() { return port; } public void setPort(int port) { this.port = port; } public String getUser() { return user; } public void setUser(String user) { this.user = user; } public String getPassword() { return password; } public void setPassword(String password) { this.password = password; } }
(4)Cookies:可以用于认证数据设置
1)全局Cookies设置:在创建HttpClient时
/** * 设置全局Cookies * * @param cookies * @return */ public HttpClient setGlobeCookieHttpClient(Map<String, String> cookies) { HttpClient client = null; if (cookies != null && cookies.size() > 0) { BasicCookieStore cookieStore = new BasicCookieStore(); for (Entry<String, String> c : cookies.entrySet()) { BasicClientCookie cookie = new BasicClientCookie(c.getKey(), c.getValue()); cookie.setDomain("sina.com"); cookie.setPath("/"); cookieStore.addCookie(cookie); } client = HttpClientBuilder.create().setDefaultCookieStore(cookieStore).build(); } else { client = HttpClients.createDefault(); } return client; }
2)请求Cookies设置
法一:直接在请求头添加
/** * 设置Cookie方法1 * * @param request * @param cookies */ public void setRequestCookiesStr(HttpUriRequest request, Map<String, String> cookies) { StringBuilder cookieStr = new StringBuilder(); if (cookies != null && cookies.size() > 0) { for (Entry<String, String> cookie : cookies.entrySet()) { cookieStr.append(cookie.getKey()).append('=').append(cookie.getValue()).append(';'); } cookieStr.deleteCharAt(cookieStr.length() - 1); request.addHeader("Cookie", cookieStr.toString()); } }
法二:请求是通过context设置
/** * 设置Cookie 方法2 * * httpclient.execute(request, context) 方法进行添加 * * @param cookies * @return */ public HttpContext getetRequestCookieContext(Map<String, String> cookies) { HttpContext localContext = null; if (cookies != null && cookies.size() > 0) { BasicCookieStore cookieStore = new BasicCookieStore(); for (Entry<String, String> c : cookies.entrySet()) { BasicClientCookie cookie = new BasicClientCookie(c.getKey(), c.getValue()); cookie.setDomain("sina.com"); cookie.setPath("/"); cookieStore.addCookie(cookie); } localContext = new BasicHttpContext(); localContext.setAttribute(HttpClientContext.COOKIE_STORE, cookieStore); } return localContext; }
3)读取响应的Cookies
/** * 响应中获取cookie * * @param response */ public void getResponseCookies(HttpResponse response) { //法1 HeaderIterator headerIter = response.headerIterator("Set-Cookie"); while (headerIter.hasNext()) { Object obj = headerIter.next(); if (obj != null) { String cookie = ((Header) headerIter.next()).getValue(); String cookieRecord = cookie.substring(0, cookie.indexOf(';')); System.out.println(cookieRecord); } } //法2 HeaderElementIterator headerElementIter = new BasicHeaderElementIterator(response.headerIterator("Set-Cookie")); while (headerElementIter.hasNext()) { HeaderElement elem = headerElementIter.nextElement(); System.out.println("Element : " + elem.getName() + " = " + elem.getValue()); NameValuePair[] params = elem.getParameters(); for (int i = 0; i < params.length; i++) { System.out.println(" Params : " + params[i].getName() + " | " + params[i].getValue()); } } }
附录:完整代码
package x.http.simple.httpclient; import java.util.ArrayList; import java.util.List; import java.util.Map; import java.util.Map.Entry; import org.apache.http.Header; import org.apache.http.HeaderElement; import org.apache.http.HeaderElementIterator; import org.apache.http.HeaderIterator; import org.apache.http.HttpEntity; import org.apache.http.HttpHost; import org.apache.http.HttpResponse; import org.apache.http.HttpStatus; import org.apache.http.NameValuePair; import org.apache.http.StatusLine; import org.apache.http.auth.AuthScope; import org.apache.http.auth.UsernamePasswordCredentials; import org.apache.http.client.CredentialsProvider; import org.apache.http.client.HttpClient; import org.apache.http.client.config.RequestConfig; import org.apache.http.client.entity.UrlEncodedFormEntity; 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.client.methods.HttpRequestBase; import org.apache.http.client.methods.HttpUriRequest; import org.apache.http.client.protocol.HttpClientContext; import org.apache.http.impl.client.BasicCookieStore; import org.apache.http.impl.client.BasicCredentialsProvider; import org.apache.http.impl.client.CloseableHttpClient; import org.apache.http.impl.client.HttpClientBuilder; import org.apache.http.impl.client.HttpClients; import org.apache.http.impl.cookie.BasicClientCookie; import org.apache.http.message.BasicHeaderElementIterator; import org.apache.http.message.BasicNameValuePair; import org.apache.http.protocol.BasicHttpContext; import org.apache.http.protocol.HttpContext; import org.apache.http.util.EntityUtils; import x.http.simple.HttpProxy; public class HttpClientDemo { private CloseableHttpClient httpclient; public HttpClientDemo() { this(null); } /** * 代理方式 * * @param proxy */ public HttpClientDemo(HttpProxy proxy) { if (proxy != null) { httpclient = getHttpClientWithProxy(proxy); } else { httpclient = HttpClients.createDefault(); } } // 获得设置代理的httpClent实例 private CloseableHttpClient getHttpClientWithProxy(HttpProxy proxy) { HttpHost proxyHost = new HttpHost(proxy.getHost(), proxy.getPort()); CredentialsProvider credentialsProvider = new BasicCredentialsProvider(); credentialsProvider.setCredentials(new AuthScope(proxy.getHost(), proxy.getPort()), new UsernamePasswordCredentials(proxy.getUser(), proxy.getPassword())); return HttpClients.custom().setProxy(proxyHost).setDefaultCredentialsProvider(credentialsProvider).build(); } /** * 发送get请求 * * @param url * @throws Exception */ public byte[] sendGetRequest(String url) throws Exception { HttpGet httpGet = new HttpGet(url); System.out.println("Send Get Request : " + url); return sendRequest(httpGet); } /** * 发送post 请求 * * @param request * @throws Exception */ public byte[] sendPostRequest(String url, Map<String, String> params) throws Exception { HttpPost httpPost = new HttpPost(url); // 设置参数 if (params != null && params.size() > 0) { List<NameValuePair> nvps = new ArrayList<NameValuePair>(); for (Entry<String, String> param : params.entrySet()) { nvps.add(new BasicNameValuePair(param.getKey(), param.getValue())); } httpPost.setEntity(new UrlEncodedFormEntity(nvps)); } System.out.println("Send Post Request : " + url + " , " + params); return sendRequest(httpPost); } // 底层请求打印页面 private byte[] sendRequest(HttpRequestBase request) throws Exception { CloseableHttpResponse response = httpclient.execute(request); // 设置超时 setTimeOut(request, 5000); // 获取返回的状态列表 StatusLine statusLine = response.getStatusLine(); System.out.println("StatusLine : " + statusLine); if (statusLine.getStatusCode() == HttpStatus.SC_OK) { try { // 获取response entity HttpEntity entity = response.getEntity(); System.out.println("getContentType : " + entity.getContentType().getValue()); System.out.println("getContentEncoding : " + entity.getContentEncoding().getValue()); // 读取响应内容 byte[] responseBody = EntityUtils.toByteArray(entity); // 关闭响应流 EntityUtils.consume(entity); return responseBody; } finally { response.close(); } } return null; } // 设置超时重定向 private void setTimeOut(HttpRequestBase request, int timeout) { RequestConfig requestConfig = RequestConfig.custom().setConnectionRequestTimeout(timeout) .setConnectTimeout(timeout).setSocketTimeout(timeout).setRedirectsEnabled(true).build(); request.setConfig(requestConfig); } /** * 设置全局Cookies * * @param cookies * @return */ public HttpClient setGlobeCookieHttpClient(Map<String, String> cookies) { HttpClient client = null; if (cookies != null && cookies.size() > 0) { BasicCookieStore cookieStore = new BasicCookieStore(); for (Entry<String, String> c : cookies.entrySet()) { BasicClientCookie cookie = new BasicClientCookie(c.getKey(), c.getValue()); cookie.setDomain("sina.com"); cookie.setPath("/"); cookieStore.addCookie(cookie); } client = HttpClientBuilder.create().setDefaultCookieStore(cookieStore).build(); } else { client = HttpClients.createDefault(); } return client; } /** * 设置Cookie方法1 * * @param request * @param cookies */ public void setRequestCookiesStr(HttpUriRequest request, Map<String, String> cookies) { StringBuilder cookieStr = new StringBuilder(); if (cookies != null && cookies.size() > 0) { for (Entry<String, String> cookie : cookies.entrySet()) { cookieStr.append(cookie.getKey()).append('=').append(cookie.getValue()).append(';'); } cookieStr.deleteCharAt(cookieStr.length() - 1); request.addHeader("Cookie", cookieStr.toString()); } } /** * 设置Cookie 方法2 * * httpclient.execute(request, context) 方法进行添加 * * @param cookies * @return */ public HttpContext getetRequestCookieContext(Map<String, String> cookies) { HttpContext localContext = null; if (cookies != null && cookies.size() > 0) { BasicCookieStore cookieStore = new BasicCookieStore(); for (Entry<String, String> c : cookies.entrySet()) { BasicClientCookie cookie = new BasicClientCookie(c.getKey(), c.getValue()); cookie.setDomain("sina.com"); cookie.setPath("/"); cookieStore.addCookie(cookie); } localContext = new BasicHttpContext(); localContext.setAttribute(HttpClientContext.COOKIE_STORE, cookieStore); } return localContext; } /** * 响应中获取cookie * * @param response */ public void getResponseCookies(HttpResponse response) { // 法1 HeaderIterator headerIter = response.headerIterator("Set-Cookie"); while (headerIter.hasNext()) { Object obj = headerIter.next(); if (obj != null) { String cookie = ((Header) headerIter.next()).getValue(); String cookieRecord = cookie.substring(0, cookie.indexOf(';')); System.out.println(cookieRecord); } } // 法2 HeaderElementIterator headerElementIter = new BasicHeaderElementIterator(response.headerIterator("Set-Cookie")); while (headerElementIter.hasNext()) { HeaderElement elem = headerElementIter.nextElement(); System.out.println("Element : " + elem.getName() + " = " + elem.getValue()); NameValuePair[] params = elem.getParameters(); for (int i = 0; i < params.length; i++) { System.out.println(" Params : " + params[i].getName() + " | " + params[i].getValue()); } } } public void shutdown() throws Exception { httpclient.close(); } public static void main(String[] args) throws Exception { String url = "http://www.google.com.hk"; HttpClientDemo httpclient = new HttpClientDemo(); byte[] getResponse = httpclient.sendGetRequest(url); System.out.println("Get Body : " + new String(getResponse, "utf-8")); byte[] postResponse = httpclient.sendPostRequest(url, null); System.out.println("Get Body : " + new String(postResponse, "utf-8")); httpclient.shutdown(); } }
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