HTTP客户端工具

灰太狼 2023-10-18 19:04 73阅读 0赞

## 使用jdk原生URLConnection发送Post请求和Get请求的HTTP客户端工具 ##

package com.douyin.util;
    
    import java.io.BufferedReader;
    import java.io.IOException;
    import java.io.InputStreamReader;
    import java.io.PrintWriter;
    import java.net.URL;
    import java.net.URLConnection;
    
    /**
     * HTTP客户端工具
     *
     */
    public class HttpClientUtil {
    	/**
    	 * 发送Get请求
    	 * 
    	 * @param url
    	 *            发送请求的URL
    	 * @param param
    	 *            请求参数，请求参数应该是name1=value1&name2=value2的形式。
    	 * @return URL所代表远程资源的响应
    	 */
    	public static String sendGet(String url, String param) {
    		String result = "";
    		BufferedReader in = null;
    		try {
    			String urlName = url + "?" + param;
    			URL realUrl = new URL(urlName);
    			// 打开和URL之间的连接
    			URLConnection conn = realUrl.openConnection();
    			// 设置通用的请求属性
    			conn.setRequestProperty("accept", "*/*");
    			conn.setRequestProperty("connection", "Keep-Alive");
    			conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");
    			// 建立实际的连接
    			conn.connect();
    			// 获取所有响应头字段
    			// Map<String, List<String>> map = conn.getHeaderFields();
    			// 定义BufferedReader输入流来读取URL的响应
    			in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
    			String line;
    			while ((line = in.readLine()) != null) {
    				result += "\n" + line;
    			}
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 使用finally块来关闭输入流
    		finally {
    			try {
    				if (in != null) {
    					in.close();
    				}
    			} catch (IOException ex) {
    				ex.printStackTrace();
    			}
    		}
    		return result;
    	}
    
    	/**
    	 * 发送POST请求
    	 * 
    	 * @param url
    	 *            发送请求的URL
    	 * @param param
    	 *            请求参数，请求参数应该是name1=value1&name2=value2的形式。
    	 * @return URL所代表远程资源的响应
    	 */
    	public static String sendPost(String url, String param) {
    		PrintWriter out = null;
    		BufferedReader in = null;
    		String result = "";
    		try {
    			URL realUrl = new URL(url);
    			// 打开和URL之间的连接
    			URLConnection conn = realUrl.openConnection();
    			// 设置cookie
    			// conn.setRequestProperty("cookie", "");
    			// 设置通用的请求属性
    			conn.setRequestProperty("accept", "*/*");
    			conn.setRequestProperty("connection", "Keep-Alive");
    			conn.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1; SV1)");
    			// 发送POST请求必须设置如下两行
    			conn.setDoOutput(true);
    			conn.setDoInput(true);
    			// 获取URLConnection对象对应的输出流
    			out = new PrintWriter(conn.getOutputStream());
    			// 发送请求参数
    			out.print(param);
    			// flush输出流的缓冲
    			out.flush();
    			// 定义BufferedReader输入流来读取URL的响应
    			in = new BufferedReader(new InputStreamReader(conn.getInputStream()));
    			String line;
    			while ((line = in.readLine()) != null) {
    				result += "\n" + line;
    			}
    		} catch (Exception e) {
    			e.printStackTrace();
    		}
    		// 使用finally块来关闭输出流、输入流
    		finally {
    			try {
    				if (out != null) {
    					out.close();
    				}
    				if (in != null) {
    					in.close();
    				}
    			} catch (IOException ex) {
    				ex.printStackTrace();
    			}
    		}
    		return result;
    	}
    }