Java实现Http的Post、Get、代理访问请求

转载自http://www.oschina.net/code/snippet_2266157_45252

package getMethod;

import java.io.BufferedReader; 
import java.io.IOException;
import java.io.InputStream; 
import java.io.InputStreamReader; 
import java.io.OutputStreamWriter;
import java.io.UnsupportedEncodingException; 
import java.net.HttpURLConnection; 
import java.net.InetSocketAddress;
import java.net.Proxy;
import java.net.URL;
import java.net.URLConnection;
import java.util.List;
import java.util.Map;
 
/**
 * Http请求工具类
 * @author snowfigure
 * @since 2014-8-24 13:30:56
 * @version v1.0.1
 */
public class HttpRequestUtil {
    static boolean proxySet = false;
    static String proxyHost = "127.0.0.1";
    static int proxyPort = 8087;
    /**
     * 编码
     * @param source
     * @return
     */
    public static String urlEncode(String source,String encode) { 
        String result = source; 
        try { 
            result = java.net.URLEncoder.encode(source,encode); 
        } catch (UnsupportedEncodingException e) { 
            e.printStackTrace(); 
            return "0"; 
        } 
        return result; 
    }
    public static String urlEncodeGBK(String source) { 
        String result = source; 
        try { 
            result = java.net.URLEncoder.encode(source,"GBK"); 
        } catch (UnsupportedEncodingException e) { 
            e.printStackTrace(); 
            return "0"; 
        } 
        return result; 
    }
    /**
     * 发起http请求获取返回结果
     * @param req_url 请求地址
     * @return
     */
    public static String httpRequest(String req_url) {
        StringBuffer buffer = new StringBuffer(); 
        try { 
            URL url = new URL(req_url); 
            HttpURLConnection httpUrlConn = (HttpURLConnection) url.openConnection(); 
  
            httpUrlConn.setDoOutput(false); 
            httpUrlConn.setDoInput(true); 
            httpUrlConn.setUseCaches(false); 
  
            httpUrlConn.setRequestMethod("GET"); 
            httpUrlConn.connect(); 
  
            // 将返回的输入流转换成字符串 
            InputStream inputStream = httpUrlConn.getInputStream(); 
            InputStreamReader inputStreamReader = new InputStreamReader(inputStream, "utf-8"); 
            BufferedReader bufferedReader = new BufferedReader(inputStreamReader); 
  
            String str = null; 
            while ((str = bufferedReader.readLine()) != null) { 
                buffer.append(str); 
            } 
            bufferedReader.close(); 
            inputStreamReader.close(); 
            // 释放资源 
            inputStream.close(); 
            inputStream = null; 
            httpUrlConn.disconnect(); 
  
        } catch (Exception e) { 
            System.out.println(e.getStackTrace()); 
        } 
        return buffer.toString(); 
    } 
      
    /**
     * 发送http请求取得返回的输入流
     * @param requestUrl 请求地址
     * @return InputStream
     */
    public static InputStream httpRequestIO(String requestUrl) { 
        InputStream inputStream = null; 
        try { 
            URL url = new URL(requestUrl); 
            HttpURLConnection httpUrlConn = (HttpURLConnection) url.openConnection(); 
            httpUrlConn.setDoInput(true); 
            httpUrlConn.setRequestMethod("GET"); 
            httpUrlConn.connect(); 
            // 获得返回的输入流 
            inputStream = httpUrlConn.getInputStream(); 
        } catch (Exception e) { 
            e.printStackTrace(); 
        } 
        return inputStream; 
    }
    
    
    /**
     * 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;
        try {
            String urlNameString = url + "?" + param;
            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。
     * @param isproxy
     *               是否使用代理模式
     * @return 所代表远程资源的响应结果
     */
    public static String sendPost(String url, String param,boolean isproxy) {
        OutputStreamWriter out = null;
        BufferedReader in = null;
        String result = "";
        try {
            URL realUrl = new URL(url);
            HttpURLConnection conn = null;
            if(isproxy){//使用代理模式
                @SuppressWarnings("static-access")
                Proxy proxy = new Proxy(Proxy.Type.DIRECT.HTTP, new InetSocketAddress(proxyHost, proxyPort));
                conn = (HttpURLConnection) realUrl.openConnection(proxy);
            }else{
                conn = (HttpURLConnection) realUrl.openConnection();
            }
            // 打开和URL之间的连接
            
            // 发送POST请求必须设置如下两行
            conn.setDoOutput(true);
            conn.setDoInput(true);
            conn.setRequestMethod("POST");    // POST方法
            
            
            // 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", "application/x-www-form-urlencoded");
            
            conn.connect();
            
            // 获取URLConnection对象对应的输出流
            out = new OutputStreamWriter(conn.getOutputStream(), "UTF-8");
            // 发送请求参数
            out.write(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 += 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) {
        //demo:代理访问
        String url = "http://192.168.0.200:8085/site-admin-v2.6/site/accuntState";
        String para = "userId=1806001100005";
        
        String sr=HttpRequestUtil.sendGet(url,para);
        System.out.println(sr);
    }
    

}