Httpclient发送http请求

1.引入httpclient 所需要的jars

<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpclient</artifactId>
<version>4.5.2</version>
</dependency>
<dependency>
<groupId>org.apache.httpcomponents</groupId>
<artifactId>httpmime</artifactId>
<version>4.5.2</version>
</dependency>

2.实现HttpConnectionManager，里面有连接池保存连接。

package ****.httpclient;

import java.security.NoSuchAlgorithmException;

import javax.annotation.PostConstruct;
import javax.net.ssl.SSLContext;

import org.apache.http.config.Registry;
import org.apache.http.config.RegistryBuilder;
import org.apache.http.conn.socket.ConnectionSocketFactory;
import org.apache.http.conn.socket.LayeredConnectionSocketFactory;
import org.apache.http.conn.socket.PlainConnectionSocketFactory;
import org.apache.http.conn.ssl.SSLConnectionSocketFactory;
import org.apache.http.impl.client.CloseableHttpClient;
import org.apache.http.impl.client.HttpClients;
import org.apache.http.impl.conn.PoolingHttpClientConnectionManager;
import org.springframework.stereotype.Component;

@Component("httpConnectionManager")
public class HttpConnectionManager {
    PoolingHttpClientConnectionManager cm = null;

    @PostConstruct
    public void init() {
        LayeredConnectionSocketFactory sslsf = null;
        try {
            sslsf = new SSLConnectionSocketFactory(SSLContext.getDefault());
        } catch (NoSuchAlgorithmException e) {
            e.printStackTrace();
        }


        Registry<ConnectionSocketFactory> socketFactoryRegistry = RegistryBuilder.<ConnectionSocketFactory> create()
.register("https", sslsf)
.register("http", new PlainConnectionSocketFactory())
.build();
        cm =new PoolingHttpClientConnectionManager(socketFactoryRegistry);
        cm.setMaxTotal(200);
        cm.setDefaultMaxPerRoute(20);
    }

    public CloseableHttpClient getHttpClient() {
        CloseableHttpClient httpClient = HttpClients.custom()
.setConnectionManager(cm)
.build();

/*CloseableHttpClient httpClient = HttpClients.createDefault();//如果不采用连接池就是这种方式获取连接*/
        return httpClient;
    }
}

3.实现HttpClientUtil

package *****.httpclient;

import java.io.File;
import java.io.IOException;
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.ClientProtocolException;
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.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.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Component;

@Component("httpClientUtil")
public class HttpClientUtil {

@Autowired
private HttpConnectionManager httpConnectionManager;

/** 
 * 发送 post请求 
 * @param httpUrl 地址 
 * @throws IOException 
 * @throws ClientProtocolException 
 */  
public String sendHttpPost(String httpUrl) throws ClientProtocolException, IOException {  
        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) 
 * @throws IOException 
 * @throws ClientProtocolException 
 */  
public String sendHttpPost(String httpUrl, String params) throws ClientProtocolException, IOException {  
        HttpPost httpPost = new HttpPost(httpUrl);// 创建httpPost 
//设置参数 
        StringEntity stringEntity = new StringEntity(params, "UTF-8");  
        stringEntity.setContentType("application/x-www-form-urlencoded");  
        httpPost.setEntity(stringEntity);  
return sendHttpPost(httpPost);  
    }  

/** 
 * 发送 post请求 
 * @param httpUrl 地址 
 * @param maps 参数 
 * @throws IOException 
 * @throws ClientProtocolException 
 */  
public String sendHttpPost(String httpUrl, Map<String, String> maps) throws ClientProtocolException, IOException {  
        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)));  
        }  
        httpPost.setEntity(new UrlEncodedFormEntity(nameValuePairs, "UTF-8"));  
return sendHttpPost(httpPost);  
    }  


/** 
 * 发送 post请求（带文件） 
 * @param httpUrl 地址 
 * @param maps 参数 
 * @param fileLists 附件 
 * @throws IOException 
 * @throws ClientProtocolException 
 */  
public String sendHttpPost(String httpUrl, Map<String, String> maps, List<File> fileLists) throws ClientProtocolException, IOException {  
        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 
 * @throws IOException 
 * @throws ClientProtocolException 
 */  
private String sendHttpPost(HttpPost httpPost) throws ClientProtocolException, IOException {  

        CloseableHttpClient httpClient = httpConnectionManager.getHttpClient();
        CloseableHttpResponse response=null;
        response = httpClient.execute(httpPost);
        HttpEntity entity = null;  
        String responseContent = null;  
// 执行请求 
        entity = response.getEntity();  
        responseContent = EntityUtils.toString(entity, "UTF-8");  
return responseContent;  
    }  


/** 
 * 发送 get请求 
 * @param httpUrl 
 * @throws IOException 
 * @throws ClientProtocolException 
 */  
public String sendHttpGet(String httpUrl) throws ClientProtocolException, IOException {  
        HttpGet httpGet = new HttpGet(httpUrl);// 创建get请求 
return sendHttpGet(httpGet);  
    }  

/** 
 * 发送Get请求 
 * @param httpPost 
 * @return 
 * @throws IOException 
 * @throws ClientProtocolException 
 */  
private String sendHttpGet(HttpGet httpGet) throws ClientProtocolException, IOException {  
        CloseableHttpClient httpClient = httpConnectionManager.getHttpClient();
        CloseableHttpResponse response=null; 
        HttpEntity entity = null;  
        String responseContent = null;  
// 执行请求 
        response = httpClient.execute(httpGet);  
        entity = response.getEntity();  
        responseContent = EntityUtils.toString(entity, "UTF-8");  
return responseContent;  
    }  

}

4.调用HttpClientUtil里面的方法。