HttpClient 是 Apache Jakarta Common 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,而且它支持 HTTP 协议最新的版本和建议。HttpClient 已经应用在不少的项目中,好比 Apache Jakarta 上很著名的另外两个开源项目 Cactus 和 HTMLUnit 都使用了 HttpClient。
HttpClient 提供的主要的功能,要知道更多详细的功能能够参见 HttpClient 的主页。
实现了全部 HTTP 的方法(GET,POST,PUT,HEAD 等)
支持自动转向
支持 HTTPS 协议
支持代理服务器等
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;
/**
* 封装了采用HttpClient发送HTTP请求的方法
* @see 本工具所采用的是HttpComponents-Client-4.2.1
* @see ===================================================================================================
* @see 开发HTTPS应用时,时常会遇到两种状况
* @see 一、测试服务器没有有效的SSL证书,客户端链接时就会抛异常
* @see javax.net.ssl.SSLPeerUnverifiedException: peer not authenticated
* @see 二、测试服务器有SSL证书,但可能因为各类不知名的缘由,它仍是会抛一堆烂码七糟的异常,诸以下面这两种
* @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 这里使用的是HttpComponents-Client-4.2.1建立的链接,因此就要告诉它使用一个不一样的TrustManager
* @see 因为SSL使用的模式是X.509,对于该模式,Java有一个特定的TrustManager,称为X509TrustManager
* @see TrustManager是一个用于检查给定的证书是否有效的类,因此咱们本身建立一个X509TrustManager实例
* @see 而在X509TrustManager实例中,若证书无效,那么TrustManager在它的checkXXX()方法中将抛出CertificateException
* @see 既然咱们要接受全部的证书,那么X509TrustManager里面的方法体中不抛出异常就好了
* @see 而后建立一个SSLContext并使用X509TrustManager实例来初始化之
* @see 接着经过SSLContext建立SSLSocketFactory,最后将SSLSocketFactory注册给HttpClient就能够了
* @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,用于发送HTTPS的POST请求
* @history v1.2-->新增<code>sendPostRequest()</code>方法,用于发送HTTP协议报文体为任意字符串的POST请求
* @history v1.3-->新增<code>java.net.HttpURLConnection</code>实现的<code>sendPostRequestByJava()</code>
* @history v1.4-->全部POST方法中增长链接超时限制和读取超时限制
* @history v1.5-->重组各方法,并补充自动获取HTTP响应文本编码的方式,移除<code>sendPostRequestByJava()</code>
* @history v1.6-->整理GET和POST请求方法,使之更为适用
* @history v1.7-->修正<code>sendPostRequest()</code>请求的CONTENT_TYPE头信息,并优化各方法参数及内部处理细节
* @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(){}
/**
* 发送HTTP_GET请求
* @see 1)该方法会自动关闭链接,释放资源
* @see 2)方法内设置了链接和读取超时时间,单位为毫秒,超时或发生其它异常时方法会自动返回"通讯失败"字符串
* @see 3)请求参数含中文时,经测试可直接传入中文,HttpClient会自动编码发给Server,应用时应根据实际效果决定传入前是否转码
* @see 4)该方法会自动获取到响应消息头中[Content-Type:text/html; charset=GBK]的charset值做为响应报文的解码字符集
* @see 若响应消息头中无Content-Type属性,则会使用HttpClient内部默认的ISO-8859-1做为响应报文的解码字符集
* @param requestURL 请求地址(含参数)
* @return 远程主机响应正文
*/
public static String sendGetRequest(String reqURL){
String respContent = "通讯失败"; //响应内容
HttpClient httpClient = new DefaultHttpClient(); //建立默认的httpClient实例
//设置代理服务器
//httpClient.getParams().setParameter(ConnRoutePNames.DEFAULT_PROXY, new HttpHost("10.0.0.4", 8080));
httpClient.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 10000); //链接超时10s
httpClient.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 20000); //读取超时20s
HttpGet httpGet = new HttpGet(reqURL); //建立org.apache.http.client.methods.HttpGet
try{
HttpResponse response = httpClient.execute(httpGet); //执行GET请求
HttpEntity entity = response.getEntity(); //获取响应实体
if(null != entity){
//respCharset=EntityUtils.getContentCharSet(entity)也能够获取响应编码,但从4.1.3开始不建议使用这种方式
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应答状态行信息
String respHeaderMsg = respHeaderDatas.toString().trim(); //HTTP应答报文头信息
String respBodyMsg = respContent; //HTTP应答报文体信息
System.out.println("HTTP应答完整报文=[" + 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("请求通讯[" + reqURL + "]时链接超时,堆栈轨迹以下", cte);
} catch (SocketTimeoutException ste){
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时读取超时,堆栈轨迹以下", ste);
}catch(ClientProtocolException cpe){
//该异常一般是协议错误致使:好比构造HttpGet对象时传入协议不对(将'http'写成'htp')or响应内容不符合HTTP协议要求等
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时协议异常,堆栈轨迹以下", cpe);
}catch(ParseException pe){
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时解析异常,堆栈轨迹以下", pe);
}catch(IOException ioe){
//该异常一般是网络缘由引发的,如HTTP服务器未启动等
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时网络异常,堆栈轨迹以下", ioe);
}catch (Exception e){
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时偶遇异常,堆栈轨迹以下", e);
}finally{
//关闭链接,释放资源
httpClient.getConnectionManager().shutdown();
}
return respContent;
}
/**
* 发送HTTP_POST请求
* @see 1)该方法容许自定义任何格式和内容的HTTP请求报文体
* @see 2)该方法会自动关闭链接,释放资源
* @see 3)方法内设置了链接和读取超时时间,单位为毫秒,超时或发生其它异常时方法会自动返回"通讯失败"字符串
* @see 4)请求参数含中文等特殊字符时,可直接传入本方法,并指明其编码字符集encodeCharset参数,方法内部会自动对其转码
* @see 5)该方法在解码响应报文时所采用的编码,取自响应消息头中的[Content-Type:text/html; charset=GBK]的charset值
* @see 若响应消息头中未指定Content-Type属性,则会使用HttpClient内部默认的ISO-8859-1
* @param reqURL 请求地址
* @param reqData 请求参数,如有多个参数则应拼接为param11=value11&22=value22&33=value33的形式
* @param encodeCharset 编码字符集,编码请求数据时用之,此参数为必填项(不能为""或null)
* @return 远程主机响应正文
*/
public static String sendPostRequest(String reqURL, String reqData, String encodeCharset){
String reseContent = "通讯失败";
HttpClient httpClient = new DefaultHttpClient();
httpClient.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 10000);
httpClient.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 20000);
HttpPost httpPost = new HttpPost(reqURL);
//因为下面使用的是new StringEntity(....),因此默认发出去的请求报文头中CONTENT_TYPE值为text/plain; charset=ISO-8859-1
//这就有可能会致使服务端接收不到POST过去的参数,好比运行在Tomcat6.0.36中的Servlet,因此咱们手工指定CONTENT_TYPE头消息
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("请求通讯[" + reqURL + "]时链接超时,堆栈轨迹以下", cte);
} catch (SocketTimeoutException ste){
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时读取超时,堆栈轨迹以下", ste);
}catch(Exception e){
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时偶遇异常,堆栈轨迹以下", e);
}finally{
httpClient.getConnectionManager().shutdown();
}
return reseContent;
}
/**
* 发送HTTP_POST_SSL请求
* @see 1)该方法会自动关闭链接,释放资源
* @see 2)该方法亦可处理普通的HTTP_POST请求
* @see 3)当处理HTTP_POST_SSL请求时,默认请求的是对方443端口,除非reqURL参数中指明了SSL端口
* @see 4)方法内设置了链接和读取超时时间,单位为毫秒,超时或发生其它异常时方法会自动返回"通讯失败"字符串
* @see 5)请求参数含中文等特殊字符时,可直接传入本方法,并指明其编码字符集encodeCharset参数,方法内部会自动对其转码
* @see 6)方法内部会自动注册443做为SSL端口,若实际使用中reqURL指定的SSL端口非443,可自行尝试更改方法内部注册的SSL端口
* @see 7)该方法在解码响应报文时所采用的编码,取自响应消息头中的[Content-Type:text/html; charset=GBK]的charset值
* @see 若响应消息头中未指定Content-Type属性,则会使用HttpClient内部默认的ISO-8859-1
* @param reqURL 请求地址
* @param params 请求参数
* @param encodeCharset 编码字符集,编码请求数据时用之,当其为null时,则取HttpClient内部默认的ISO-8859-1编码请求参数
* @return 远程主机响应正文
*/
public static String sendPostSSLRequest(String reqURL, Map<String, String> params, String encodeCharset){
String responseContent = "通讯失败";
HttpClient httpClient = new DefaultHttpClient();
httpClient.getParams().setParameter(CoreConnectionPNames.CONNECTION_TIMEOUT, 10000);
httpClient.getParams().setParameter(CoreConnectionPNames.SO_TIMEOUT, 20000);
//建立TrustManager()
//用于解决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
//用于解决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与SSL3.0基本上没有太大的差异,可粗略理解为TLS是SSL的继承者,但它们使用的是相同的SSLContext
SSLContext sslContext = SSLContext.getInstance(SSLSocketFactory.TLS);
//使用TrustManager来初始化该上下文,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);
//经过SchemeRegistry将SSLSocketFactory注册到HttpClient上
httpClient.getConnectionManager().getSchemeRegistry().register(new Scheme("https", 443, socketFactory));
//建立HttpPost
HttpPost httpPost = new HttpPost(reqURL);
//因为下面使用的是new UrlEncodedFormEntity(....),因此这里不须要手工指定CONTENT_TYPE为application/x-www-form-urlencoded
//由于在查看了HttpClient的源码后发现,UrlEncodedFormEntity所采用的默认CONTENT_TYPE就是application/x-www-form-urlencoded
//httpPost.setHeader(HTTP.CONTENT_TYPE, "application/x-www-form-urlencoded; charset=" + encodeCharset);
//构建POST请求的表单参数
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("请求通讯[" + reqURL + "]时链接超时,堆栈轨迹以下", cte);
} catch (SocketTimeoutException ste){
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时读取超时,堆栈轨迹以下", ste);
} catch (Exception e) {
LogUtil.getLogger().error("请求通讯[" + reqURL + "]时偶遇异常,堆栈轨迹以下", e);
} finally {
httpClient.getConnectionManager().shutdown();
}
return responseContent;
}
} html