Java http请求
package com.expai.utils; import java.io.BufferedReader; import java.io.IOException; import java.io.InputStreamReader; import java.io.OutputStreamWriter; import java.io.PrintWriter; import java.net.HttpURLConnection; import java.net.URL; import java.net.URLConnection; import java.util.List; import java.util.Map; import org.apache.log4j.Logger; public class HttpEmbed { private static final Logger log = Logger.getLogger(HttpEmbed.class); /** * 向指定URL发送GET方法的请求 * * @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结果 */ public static String sendGet(String url, String param) { String result = ""; BufferedReader in = null; String urlNameString=null; try { if(param==null){ urlNameString = url; }else{ urlNameString = url + "?" + param; } log.info("url==========================="+urlNameString); URL realUrl = new URL(urlNameString); // 打开和URL之间的连接 URLConnection connection = realUrl.openConnection(); // 设置通用的请求属性 connection.setRequestProperty("accept", "*/*"); connection.setRequestProperty("connection", "Keep-Alive"); connection.setRequestProperty("user-agent", "Mozilla/4.0 (compatible; MSIE 6.0; Windows NT 5.1;SV1)"); // 建立实际的连接 connection.connect(); // 获取所有响应头字段 Map<String, List<String>> map = connection.getHeaderFields(); // 遍历所有的响应头字段 /* for (String key : map.keySet()) { System.out.println(key + "--->" + map.get(key)); } // 定义 BufferedReader输入流来读取URL的响应 in = new BufferedReader(new InputStreamReader( connection.getInputStream())); String line; while ((line = in.readLine()) != null) { result += line; }*/ } catch (Exception e) { System.out.println("发送GET请求出现异常!" + e); e.printStackTrace(); } // 使用finally块来关闭输入流 finally { try { if (in != null) { in.close(); } } catch (Exception e2) { e2.printStackTrace(); } } return result; } /** * 向指定 URL 发送POST方法的请求 * * @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 所代表远程资源的响应结果 */ 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)"); //conn.setRequestProperty("Content-Type", "text/xml; charset=utf-8"); // 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 log.info("post url==========================="+url+"?"+param); 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 += line; } } catch (Exception e) { System.out.println("发送 POST 请求出现异常!"+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; } public static void main(String[] args) { String str = HttpEmbed.sendGet("http://42.121.1.151:9000/hotimage", "callback=jsonp3&action=pagingImageNew&number=50&categoryId=chinayes.com&pageNum=0"); System.out.println("============="+str); } public static String httpPost(String url, String sb ) { URL u = null; HttpURLConnection con = null; //构建请求参数 /*StringBuffer sb = new StringBuffer(); if(params!=null){ for (Entry<String, String> e : params.entrySet()) { sb.append(e.getKey()); sb.append("="); sb.append(e.getValue()); sb.append("&"); } sb.substring(0, sb.length() - 1); }*/ System.out.println("send_url:"+url); System.out.println("send_data:"+sb); //尝试发送请求 try { u = new URL(url); con = (HttpURLConnection) u.openConnection(); con.setRequestMethod("POST"); con.setDoOutput(true); con.setDoInput(true); con.setUseCaches(false); con.setRequestProperty("Content-Type", "application/x-www-form-urlencoded"); OutputStreamWriter osw = new OutputStreamWriter(con.getOutputStream(), "UTF-8"); osw.write(sb); osw.flush(); osw.close(); } catch (Exception e) { e.printStackTrace(); } finally { if (con != null) { con.disconnect(); } } //读取返回内容 //StringBuffer buffer = new StringBuffer(); try { BufferedReader br = new BufferedReader(new InputStreamReader(con .getInputStream(), "UTF-8")); String temp; /*while ((temp = br.readLine()) != null) { buffer.append(temp); buffer.append("\n"); }*/ } catch (Exception e) { e.printStackTrace(); } return ""; } }