封裝HttpClientUtils工具

package cn.gzsxt.ego.base.utils;

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.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.utils.URIBuilder;
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.client.LaxRedirectStrategy;
import org.apache.http.message.BasicNameValuePair;
import org.apache.http.util.EntityUtils;
/**
 * --發送get請求的api
 * CloseableHttpClient類 ，client實現類
 * HttpClients類 ，client工具類，用於創建客戶端對象。
 * CloseableHttpResponse接口，請求的響應對象
 * URIBuilder類 ：url構建類，用於設置get請求的路徑變量
 * HttpGet類 ：get請求的發送對象
 * EntityUtils類 實體處理類
 * 
 * --發送post 請求使用的api
 * CloseableHttpClient類
 * HttpClientBuilder client構建對象，用於創建客戶端對象。
 * LaxRedirectStrategy類，post請求重定向的策略
 * CloseableHttpResponse 請求的響應對象
 * HttpPost post請求的發送對象
 * NameValuePair 類，用於設置參數值
 * UrlEncodedFormEntity：用於設置表單參數給發送對象HttpPost
 * 
 * @author ranger
 *
 */
public class HttpClientUtils {

public static String doGet(String url,Map<String, String> params){
		
		//獲取httpclient客戶端
		CloseableHttpClient httpclient = HttpClients.createDefault();
		
		String resultString = "";
		
		CloseableHttpResponse response = null;
		
		try {
			URIBuilder builder = new URIBuilder(url);
			
			if(null!=params){
				for (String key:params.keySet()) {
					builder.setParameter(key, params.get(key));
				}
			}
			
			HttpGet get = new HttpGet(builder.build());
			
			
			response = httpclient.execute(get);
			
			System.out.println(response.getStatusLine());
			
			if(200==response.getStatusLine().getStatusCode()){
				HttpEntity entity = response.getEntity();
				resultString = EntityUtils.toString(entity, "utf-8");
			}
			
		} catch (Exception e) {
			
			e.printStackTrace();
		} finally {
			if(null!=response){
				try {
					response.close();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
			if(null!=httpclient){
				try {
					httpclient.close();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		}
		
		return resultString;
	}
	
	public static String doGet(String url){
		return doGet(url, null);
	}
	
	public static String doPost(String url,Map<String,String> params){
		/**
		 * 在4.0及以上httpclient版本中，post需要指定重定向的策略，如果不指定則按默認的重定向策略。
		 * 
		 * 獲取httpclient客戶端
		 */
		CloseableHttpClient httpclient = HttpClientBuilder.create().setRedirectStrategy( new LaxRedirectStrategy()).build();
		
		String resultString = "";
		
		CloseableHttpResponse response = null;
		
		try {
			
			
			HttpPost post = new HttpPost(url);
			
			List<NameValuePair> paramaters = new ArrayList<>();
			
			if(null!=params){
				for (String key : params.keySet()) {
					paramaters.add(new BasicNameValuePair(key,params.get(key)));
				}
				
				UrlEncodedFormEntity  formEntity = new UrlEncodedFormEntity (paramaters);
				
				post.setEntity(formEntity);
			}
			
			
			/**
			 * HTTP/1.1 403 Forbidden
			 *   原因：
			 *      有些網站，設置了反爬蟲機制
			 *   解決的辦法：
			 *      設置請求頭，偽裝瀏覽器
			 */
			post.addHeader("user-agent", "Mozilla/5.0 (Windows NT 6.3; WOW64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/63.0.3239.132 Safari/537.36");
			
			response = httpclient.execute(post);
			
			System.out.println(response.getStatusLine());
			
			if(200==response.getStatusLine().getStatusCode()){
				HttpEntity entity = response.getEntity();
				resultString = EntityUtils.toString(entity, "utf-8");
			}
			
		} catch (Exception e) {
			
			e.printStackTrace();
		} finally {
			if(null!=response){
				try {
					response.close();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
			if(null!=httpclient){
				try {
					httpclient.close();
				} catch (IOException e) {
					// TODO Auto-generated catch block
					e.printStackTrace();
				}
			}
		}
		
		return resultString;
	}
	
	public static String doPost(String url){
		return doPost(url, null);
	}
 
}