其实httpclient.jar的问题并不复杂，但是又很多的朋友都不太了解http服务器，因此呢，今天小编就来为大家分享httpclient.jar的一些知识，希望可以帮助到大家，下面我们一起来看看这个问题的分析吧！
httpclient是哪个jar
httpclient对应的jar是Apache HttpClient。
详细解释：
Apache HttpClient是一个开源的HTTP客户端库，用于Java应用程序中的网络通信。它通过方便的API允许开发者轻松与服务器交互。此库能够支持多种网络协议和通信方法，广泛用于客户端和服务端应用程序之间的数据传输。这个库并不是孤立的jar文件，而是一个由多个模块组成的项目，但通常可以通过Maven或Gradle等构建工具作为依赖项添加到项目中。此外，它还包括多种功能，如连接管理、认证方案以及更高级的功能，如流式传输、编码与解码处理等。其HTTP/HTTPS请求实现得到广泛应用和信任，支持开发者高效且安全地进行网络请求与响应交互。
Java中的httpclient4.5应该怎么使用
一、所需要的jar包
httpclient-4.5.jar
httpcore-4.4.1.jar
httpmime-4.5.jar
二、实例
Java代码
package cn.tzz.apache.httpclient;
import java.io.File;
import java.io.IOException;
import java.net.URL;
import java.util.ArrayList;
import java.util.List;
import java.util.Map;
import org.apache.http.HttpEntity;
import org.apache.http.NameValuePair;
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.conn.ssl.DefaultHostnameVerifier;
import org.apache.http.conn.util.PublicSuffixMatcher;
import org.apache.http.conn.util.PublicSuffixMatcherLoader;
import org.apache.http.entity.ContentType;
import org.apache.http.entity.StringEntity;
import org.apache.http.entity.mime.MultipartEntityBuilder;
import org.apache.http.entity.mime.content.FileBody;
import org.apache.http.entity.mime.content.StringBody;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
public class HttpClientUtil{
private RequestConfig requestConfig= RequestConfig.custom()
.setSocketTimeout(15000)
.setConnectTimeout(15000)
.setConnectionRequestTimeout(15000)
.build();
private static HttpClientUtil instance= null;
private HttpClientUtil(){}
public static HttpClientUtil getInstance(){
if(instance== null){
instance= new HttpClientUtil();
}
return instance;
}
/**
*发送 post请求
*@param httpUrl地址
*/
public String sendHttpPost(String httpUrl){
HttpPost httpPost= new HttpPost(httpUrl);//创建httpPost
return sendHttpPost(httpPost);
}
/**
*发送 post请求
*@param httpUrl地址
*@param params参数(格式:key1=value1&key2=value2)
*/
public String sendHttpPost(String httpUrl, String params){
HttpPost httpPost= new HttpPost(httpUrl);//创建httpPost
try{
//设置参数
StringEntity stringEntity= new StringEntity(params,"UTF-8");
stringEntity.setContentType("application/x-www-form-urlencoded");
httpPost.setEntity(stringEntity);
} catch(Exception e){
e.printStackTrace();
}
return sendHttpPost(httpPost);
}
/**
*发送 post请求
*@param httpUrl地址
*@param maps参数
*/
public String sendHttpPost(String httpUrl, Map<String, String> maps){
HttpPost httpPost= new HttpPost(httpUrl);//创建httpPost
//创建参数队列
List<NameValuePair> nameValuePairs= new ArrayList<NameValuePair>();
for(String key: maps.keySet()){
nameValuePairs.add(new BasicNameValuePair(key, maps.get(key)));
}
try{
httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs,"UTF-8"));
} catch(Exception e){
e.printStackTrace();
}
return sendHttpPost(httpPost);
}
/**
*发送 post请求（带文件）
*@param httpUrl地址
*@param maps参数
*@param fileLists附件
*/
public String sendHttpPost(String httpUrl, Map<String, String> maps, List<File> fileLists){
HttpPost httpPost= new HttpPost(httpUrl);//创建httpPost
MultipartEntityBuilder meBuilder= MultipartEntityBuilder.create();
for(String key: maps.keySet()){
meBuilder.addPart(key, new StringBody(maps.get(key), ContentType.TEXT_PLAIN));
}
for(File file: fileLists){
FileBody fileBody= new FileBody(file);
meBuilder.addPart("files", fileBody);
}
HttpEntity reqEntity= meBuilder.build();
httpPost.setEntity(reqEntity);
return sendHttpPost(httpPost);
}
/**
*发送Post请求
*@param httpPost
*@return
*/
private String sendHttpPost(HttpPost httpPost){
CloseableHttpClient httpClient= null;
CloseableHttpResponse response= null;
HttpEntity entity= null;
String responseContent= null;
try{
//创建默认的httpClient实例.
httpClient= HttpClients.createDefault();
httpPost.setConfig(requestConfig);
//执行请求
response= httpClient.execute(httpPost);
entity= response.getEntity();
responseContent= EntityUtils.toString(entity,"UTF-8");
} catch(Exception e){
e.printStackTrace();
} finally{
try{
//关闭连接,释放资源
if(response!= null){
response.close();
}
if(httpClient!= null){
httpClient.close();
}
} catch(IOException e){
e.printStackTrace();
}
}
return responseContent;
}
/**
*发送 get请求
*@param httpUrl
*/
public String sendHttpGet(String httpUrl){
HttpGet httpGet= new HttpGet(httpUrl);//创建get请求
return sendHttpGet(httpGet);
}
/**
*发送 get请求Https
*@param httpUrl
*/
public String sendHttpsGet(String httpUrl){
HttpGet httpGet= new HttpGet(httpUrl);//创建get请求
return sendHttpsGet(httpGet);
}
/**
*发送Get请求
*@param httpPost
*@return
*/
private String sendHttpGet(HttpGet httpGet){
CloseableHttpClient httpClient= null;
CloseableHttpResponse response= null;
HttpEntity entity= null;
String responseContent= null;
try{
//创建默认的httpClient实例.
httpClient= HttpClients.createDefault();
httpGet.setConfig(requestConfig);
//执行请求
response= httpClient.execute(httpGet);
entity= response.getEntity();
responseContent= EntityUtils.toString(entity,"UTF-8");
} catch(Exception e){
e.printStackTrace();
} finally{
try{
//关闭连接,释放资源
if(response!= null){
response.close();
}
if(httpClient!= null){
httpClient.close();
}
} catch(IOException e){
e.printStackTrace();
}
}
return responseContent;
}
/**
*发送Get请求Https
*@param httpPost
*@return
*/
private String sendHttpsGet(HttpGet httpGet){
CloseableHttpClient httpClient= null;
CloseableHttpResponse response= null;
HttpEntity entity= null;
String responseContent= null;
try{
//创建默认的httpClient实例.
PublicSuffixMatcher publicSuffixMatcher= PublicSuffixMatcherLoader.load(new URL(httpGet.getURI().toString()));
DefaultHostnameVerifier hostnameVerifier= new DefaultHostnameVerifier(publicSuffixMatcher);
httpClient= HttpClients.custom().setSSLHostnameVerifier(hostnameVerifier).build();
httpGet.setConfig(requestConfig);
//执行请求
response= httpClient.execute(httpGet);
entity= response.getEntity();
responseContent= EntityUtils.toString(entity,"UTF-8");
} catch(Exception e){
e.printStackTrace();
} finally{
try{
//关闭连接,释放资源
if(response!= null){
response.close();
}
if(httpClient!= null){
httpClient.close();
}
} catch(IOException e){
e.printStackTrace();
}
}
return responseContent;
}
}
如何使用HttpClient
直接上实例吧。
Apache官网下载 HttpClient，下不了的点击这里，下载完后解压取lib文件夹中jar包导入到项目中
在进行本例之前需要了解三个类
HttpClient代表Http客户端里面定义了很多http请求执行行为
HttpEntity消息载体,发送或者接收消息的载体,可以通过客户端请求或者服务器响应获取实例
HttpConnection代表http连接
本次实例代码
public class HttpCLientDemo
{
// HttpClient代表Http客户端
// HttpEntity消息载体,发送或者接收消息的载体,可以通过客户端请求或者服务器响应获取实例
// HttpConnection代表http连接
/**
*@param args
*/
public static void main(String[] args)
{
//创建默认的客户端实例
HttpClient httpCLient= new DefaultHttpClient();
//创建get请求实例
HttpGet httpget= new HttpGet("");
System.out.println("executing request"+httpget.getURI());
try
{
//客户端执行get请求返回响应实体
HttpResponse response= httpCLient.execute(httpget);
//服务器响应状态行
System.out.println(response.getStatusLine());
Header[] heads= response.getAllHeaders();
//打印所有响应头
for(Header h:heads){
System.out.println(h.getName()+":"+h.getValue());
}
//获取响应消息实体
HttpEntity entity= response.getEntity();
System.out.println("------------------------------------");
if(entity!= null){
//响应内容
System.out.println(EntityUtils.toString(entity));
System.out.println("----------------------------------------");
//响应内容长度
System.out.println("响应内容长度："+entity.getContentLength());
}
} catch(ClientProtocolException e){
e.printStackTrace();
} catch(IOException e){
e.printStackTrace();
}finally{
httpCLient.getConnectionManager().shutdown();
}
}
}