HttpClient 是 Apache Jakarta Common 下的子項目,用來提供高效的、最新的、功能豐富的支持 HTTP 協議的客戶端編程工具包,而且它支持 HTTP 協議最新的版本和建議。HttpClient 已經應用在不少的項目中,好比 Apache Jakarta 上很著名的另外兩個開源項目 Cactus 和 HTMLUnit 都使用了 HttpClient。
HttpClient 提供的主要的功能,要知道更多詳細的功能能夠參見 HttpClient 的主頁。
實現了全部 HTTP 的方法(GET,POST,PUT,HEAD 等)
支持自動轉向
支持 HTTPS 協議
支持代理服務器等
import java.io.IOException;
import java.net.SocketTimeoutException;
import java.nio.charset.Charset;
import java.security.cert.CertificateException;
import java.security.cert.X509Certificate;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import javax.net.ssl.SSLContext;
import javax.net.ssl.SSLException;
import javax.net.ssl.SSLSession;
import javax.net.ssl.SSLSocket;
import javax.net.ssl.TrustManager;
import javax.net.ssl.X509TrustManager;
import org.apache.http.Header;
import org.apache.http.HttpEntity;
import org.apache.http.HttpResponse;
import org.apache.http.NameValuePair;
import org.apache.http.ParseException;
import org.apache.http.client.ClientProtocolException;
import org.apache.http.client.HttpClient;
import org.apache.http.client.entity.UrlEncodedFormEntity;
import org.apache.http.client.methods.HttpGet;
import org.apache.http.client.methods.HttpPost;
import org.apache.http.conn.ConnectTimeoutException;
import org.apache.http.conn.scheme.Scheme;
import org.apache.http.conn.ssl.SSLSocketFactory;
import org.apache.http.conn.ssl.X509HostnameVerifier;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.impl.client.DefaultHttpClient;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.params.CoreConnectionPNames;
import org.apache.http.protocol.HTTP;
import org.apache.http.util.EntityUtils;
/**
* 封裝了採用HttpClient發送HTTP請求的方法
* @see 本工具所採用的是HttpComponents-Client-4.2.1
* @see ===================================================================================================
* @see 開發HTTPS應用時,時常會遇到兩種狀況
* @see 一、測試服務器沒有有效的SSL證書,客戶端鏈接時就會拋異常
* @see javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated
* @see 二、測試服務器有SSL證書,但可能因爲各類不知名的緣由,它仍是會拋一堆爛碼七糟的異常,諸以下面這兩種
* @see javax.net.ssl.SSLException: hostname in certificate didn't match: <123.125.97.66> != <123.125.97.241>
* @see javax.net.ssl.SSLHandshakeException: sun.security.validator.ValidatorException: PKIX path building failed: sun.security.provider.certpath.SunCertPathBuilderException: unable to find valid certification path to requested target
* @see ===================================================================================================
* @see 這裏使用的是HttpComponents-Client-4.2.1建立的鏈接,因此就要告訴它使用一個不一樣的TrustManager
* @see 因爲SSL使用的模式是X.509,對於該模式,Java有一個特定的TrustManager,稱爲X509TrustManager
* @see TrustManager是一個用於檢查給定的證書是否有效的類,因此咱們本身建立一個X509TrustManager實例
* @see 而在X509TrustManager實例中,若證書無效,那麼TrustManager在它的checkXXX()方法中將拋出CertificateException
* @see 既然咱們要接受全部的證書,那麼X509TrustManager裏面的方法體中不拋出異常就好了
* @see 而後建立一個SSLContext並使用X509TrustManager實例來初始化之
* @see 接着經過SSLContext建立SSLSocketFactory,最後將SSLSocketFactory註冊給HttpClient就能夠了
* @see ===================================================================================================
* @version v1.7
* @history v1.0-->新建<code>sendGetRequest()</code>和<code>sendPostRequest()</code>方法
* @history v1.1-->新增<code>sendPostSSLRequest()</code>方法,用於發送HTTPS的POST請求
* @history v1.2-->新增<code>sendPostRequest()</code>方法,用於發送HTTP協議報文體爲任意字符串的POST請求
* @history v1.3-->新增<code>java.net.HttpURLConnection</code>實現的<code>sendPostRequestByJava()</code>
* @history v1.4-->全部POST方法中增長鏈接超時限制和讀取超時限制
* @history v1.5-->重組各方法,並補充自動獲取HTTP響應文本編碼的方式,移除<code>sendPostRequestByJava()</code>
* @history v1.6-->整理GET和POST請求方法,使之更爲適用
* @history v1.7-->修正<code>sendPostRequest()</code>請求的CONTENT_TYPE頭信息,並優化各方法參數及內部處理細節
* @create Feb 1, 2012 3:02:27 PM
* @update Jul 23, 2013 1:18:35 PM
* @author 玄玉<http://blog.csdn.net/jadyer>
*/
public class HttpClientUtil {
private HttpClientUtil(){}
/**
* 發送HTTP_GET請求
* @see 1)該方法會自動關閉鏈接,釋放資源
* @see 2)方法內設置了鏈接和讀取超時時間,單位爲毫秒,超時或發生其它異常時方法會自動返回"通訊失敗"字符串
* @see 3)請求參數含中文時,經測試可直接傳入中文,HttpClient會自動編碼發給Server,應用時應根據實際效果決定傳入前是否轉碼
* @see 4)該方法會自動獲取到響應消息頭中[Content-Type:text/html; charset=GBK]的charset值做爲響應報文的解碼字符集
* @see 若響應消息頭中無Content-Type屬性,則會使用HttpClient內部默認的ISO-8859-1做爲響應報文的解碼字符集
* @param requestURL 請求地址(含參數)
* @return 遠程主機響應正文
*/
public static String sendGetRequest(String reqURL){
String respContent = "通訊失敗"; //響應內容
HttpClient httpClient = new DefaultHttpClient(); //建立默認的httpClient實例
//設置代理服務器
//httpClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, new HttpHost("10.0.0.4", 8080));
httpClient.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 10000); //鏈接超時10s
httpClient.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 20000); //讀取超時20s
HttpGet httpGet = new HttpGet(reqURL); //建立org.apache.http.client.methods.HttpGet
try{
HttpResponse response = httpClient.execute(httpGet); //執行GET請求
HttpEntity entity = response.getEntity(); //獲取響應實體
if(null != entity){
//respCharset=EntityUtils.getContentCharSet(entity)也能夠獲取響應編碼,但從4.1.3開始不建議使用這種方式
Charset respCharset = ContentType.getOrDefault(entity).getCharset();
respContent = EntityUtils.toString(entity, respCharset);
//Consume response content
EntityUtils.consume(entity);
}
System.out.println("-------------------------------------------------------------------------------------------");
StringBuilder respHeaderDatas = new StringBuilder();
for(Header header : response.getAllHeaders()){
respHeaderDatas.append(header.toString()).append("\r\n");
}
String respStatusLine = response.getStatusLine().toString(); //HTTP應答狀態行信息
String respHeaderMsg = respHeaderDatas.toString().trim(); //HTTP應答報文頭信息
String respBodyMsg = respContent; //HTTP應答報文體信息
System.out.println("HTTP應答完整報文=[" + respStatusLine + "\r\n" + respHeaderMsg + "\r\n\r\n" + respBodyMsg + "]");
System.out.println("-------------------------------------------------------------------------------------------");
} catch (ConnectTimeoutException cte){
//Should catch ConnectTimeoutException, and don`t catch org.apache.http.conn.HttpHostConnectException
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時鏈接超時,堆棧軌跡以下", cte);
} catch (SocketTimeoutException ste){
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時讀取超時,堆棧軌跡以下", ste);
}catch(ClientProtocolException cpe){
//該異常一般是協議錯誤致使:好比構造HttpGet對象時傳入協議不對(將'http'寫成'htp')or響應內容不符合HTTP協議要求等
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時協議異常,堆棧軌跡以下", cpe);
}catch(ParseException pe){
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時解析異常,堆棧軌跡以下", pe);
}catch(IOException ioe){
//該異常一般是網絡緣由引發的,如HTTP服務器未啓動等
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時網絡異常,堆棧軌跡以下", ioe);
}catch (Exception e){
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時偶遇異常,堆棧軌跡以下", e);
}finally{
//關閉鏈接,釋放資源
httpClient.getConnectionManager().shutdown();
}
return respContent;
}
/**
* 發送HTTP_POST請求
* @see 1)該方法容許自定義任何格式和內容的HTTP請求報文體
* @see 2)該方法會自動關閉鏈接,釋放資源
* @see 3)方法內設置了鏈接和讀取超時時間,單位爲毫秒,超時或發生其它異常時方法會自動返回"通訊失敗"字符串
* @see 4)請求參數含中文等特殊字符時,可直接傳入本方法,並指明其編碼字符集encodeCharset參數,方法內部會自動對其轉碼
* @see 5)該方法在解碼響應報文時所採用的編碼,取自響應消息頭中的[Content-Type:text/html; charset=GBK]的charset值
* @see 若響應消息頭中未指定Content-Type屬性,則會使用HttpClient內部默認的ISO-8859-1
* @param reqURL 請求地址
* @param reqData 請求參數,如有多個參數則應拼接爲param11=value11&22=value22&33=value33的形式
* @param encodeCharset 編碼字符集,編碼請求數據時用之,此參數爲必填項(不能爲""或null)
* @return 遠程主機響應正文
*/
public static String sendPostRequest(String reqURL, String reqData, String encodeCharset){
String reseContent = "通訊失敗";
HttpClient httpClient = new DefaultHttpClient();
httpClient.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 10000);
httpClient.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 20000);
HttpPost httpPost = new HttpPost(reqURL);
//因爲下面使用的是new StringEntity(....),因此默認發出去的請求報文頭中CONTENT_TYPE值爲text/plain; charset=ISO-8859-1
//這就有可能會致使服務端接收不到POST過去的參數,好比運行在Tomcat6.0.36中的Servlet,因此咱們手工指定CONTENT_TYPE頭消息
httpPost.setHeader(HTTP.CONTENT_TYPE, "application/x-www-form-urlencoded; charset=" + encodeCharset);
try{
httpPost.setEntity(new StringEntity(reqData==null?"":reqData, encodeCharset));
HttpResponse response = httpClient.execute(httpPost);
HttpEntity entity = response.getEntity();
if (null != entity) {
reseContent = EntityUtils.toString(entity, ContentType.getOrDefault(entity).getCharset());
EntityUtils.consume(entity);
}
} catch (ConnectTimeoutException cte){
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時鏈接超時,堆棧軌跡以下", cte);
} catch (SocketTimeoutException ste){
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時讀取超時,堆棧軌跡以下", ste);
}catch(Exception e){
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時偶遇異常,堆棧軌跡以下", e);
}finally{
httpClient.getConnectionManager().shutdown();
}
return reseContent;
}
/**
* 發送HTTP_POST_SSL請求
* @see 1)該方法會自動關閉鏈接,釋放資源
* @see 2)該方法亦可處理普通的HTTP_POST請求
* @see 3)當處理HTTP_POST_SSL請求時,默認請求的是對方443端口,除非reqURL參數中指明瞭SSL端口
* @see 4)方法內設置了鏈接和讀取超時時間,單位爲毫秒,超時或發生其它異常時方法會自動返回"通訊失敗"字符串
* @see 5)請求參數含中文等特殊字符時,可直接傳入本方法,並指明其編碼字符集encodeCharset參數,方法內部會自動對其轉碼
* @see 6)方法內部會自動註冊443做爲SSL端口,若實際使用中reqURL指定的SSL端口非443,可自行嘗試更改方法內部註冊的SSL端口
* @see 7)該方法在解碼響應報文時所採用的編碼,取自響應消息頭中的[Content-Type:text/html; charset=GBK]的charset值
* @see 若響應消息頭中未指定Content-Type屬性,則會使用HttpClient內部默認的ISO-8859-1
* @param reqURL 請求地址
* @param params 請求參數
* @param encodeCharset 編碼字符集,編碼請求數據時用之,當其爲null時,則取HttpClient內部默認的ISO-8859-1編碼請求參數
* @return 遠程主機響應正文
*/
public static String sendPostSSLRequest(String reqURL, Map<String, String> params, String encodeCharset){
String responseContent = "通訊失敗";
HttpClient httpClient = new DefaultHttpClient();
httpClient.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 10000);
httpClient.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 20000);
//建立TrustManager()
//用於解決javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated
X509TrustManager trustManager = new X509TrustManager(){
@Override
public void checkClientTrusted(X509Certificate[] chain, String authType) throws CertificateException {}
@Override
public void checkServerTrusted(X509Certificate[] chain, String authType) throws CertificateException {}
@Override
public X509Certificate[] getAcceptedIssuers() {return null;}
};
//建立HostnameVerifier
//用於解決javax.net.ssl.SSLException: hostname in certificate didn't match: <123.125.97.66> != <123.125.97.241>
X509HostnameVerifier hostnameVerifier = new X509HostnameVerifier(){
@Override
public void verify(String host, SSLSocket ssl) throws IOException {}
@Override
public void verify(String host, X509Certificate cert) throws SSLException {}
@Override
public void verify(String host, String[] cns, String[] subjectAlts) throws SSLException {}
@Override
public boolean verify(String arg0, SSLSession arg1) {return true;}
};
try {
//TLS1.0與SSL3.0基本上沒有太大的差異,可粗略理解爲TLS是SSL的繼承者,但它們使用的是相同的SSLContext
SSLContext sslContext = SSLContext.getInstance(SSLSocketFactory.TLS);
//使用TrustManager來初始化該上下文,TrustManager只是被SSL的Socket所使用
sslContext.init(null, new TrustManager[]{trustManager}, null);
//建立SSLSocketFactory
SSLSocketFactory socketFactory = new SSLSocketFactory(sslContext, hostnameVerifier);
//經過SchemeRegistry將SSLSocketFactory註冊到HttpClient上
httpClient.getConnectionManager().getSchemeRegistry().register(new Scheme("https", 443, socketFactory));
//建立HttpPost
HttpPost httpPost = new HttpPost(reqURL);
//因爲下面使用的是new UrlEncodedFormEntity(....),因此這裏不須要手工指定CONTENT_TYPE爲application/x-www-form-urlencoded
//由於在查看了HttpClient的源碼後發現,UrlEncodedFormEntity所採用的默認CONTENT_TYPE就是application/x-www-form-urlencoded
//httpPost.setHeader(HTTP.CONTENT_TYPE, "application/x-www-form-urlencoded; charset=" + encodeCharset);
//構建POST請求的表單參數
if(null != params){
List<NameValuePair> formParams = new ArrayList<NameValuePair>();
for(Map.Entry<String,String> entry : params.entrySet()){
formParams.add(new BasicNameValuePair(entry.getKey(), entry.getValue()));
}
httpPost.setEntity(new UrlEncodedFormEntity(formParams, encodeCharset));
}
HttpResponse response = httpClient.execute(httpPost);
HttpEntity entity = response.getEntity();
if (null != entity) {
responseContent = EntityUtils.toString(entity, ContentType.getOrDefault(entity).getCharset());
EntityUtils.consume(entity);
}
} catch (ConnectTimeoutException cte){
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時鏈接超時,堆棧軌跡以下", cte);
} catch (SocketTimeoutException ste){
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時讀取超時,堆棧軌跡以下", ste);
} catch (Exception e) {
LogUtil.getLogger().error("請求通訊[" + reqURL + "]時偶遇異常,堆棧軌跡以下", e);
} finally {
httpClient.getConnectionManager().shutdown();
}
return responseContent;
}
} html