get,post请求

package com.main.comm.util;import java.awt.image.BufferedImage;import java.io.BufferedReader;import java.io.BufferedWriter;import java.io.File;import java.io.FileInputStream;import java.io.FileNotFoundException;import java.io.FileOutputStream;import java.io.FileWriter;import java.io.IOException;import java.io.InputStream;import java.io.InputStreamReader;import java.io.OutputStream;import java.io.PrintWriter;import java.io.UnsupportedEncodingException;import java.net.HttpURLConnection;import java.net.MalformedURLException;import java.net.URL;import java.net.URLConnection;import javax.imageio.ImageIO;public class DataConnection {public static String post(String addr, String params) throws UnsupportedEncodingException {  String result = "";  try {   URL url = new URL(addr);   URLConnection connection = url.openConnection();   connection.setDoOutput(true);   PrintWriter out = new PrintWriter(connection.getOutputStream());   out.write(params);   out.close();   BufferedReader in;   try {   in = new BufferedReader(new InputStreamReader(connection.getInputStream(),"utf-8"));   } catch (FileNotFoundException exception) {    java.io.InputStream err = ((HttpURLConnection) connection)      .getErrorStream();    if (err == null)     throw exception;    in = new BufferedReader(new InputStreamReader(err));   }   StringBuffer response = new StringBuffer();   String line;   while ((line = in.readLine()) != null)    response.append(line + "\n");   in.close();      result = response.toString();  } catch (MalformedURLException e) {   System.err.println(e.toString());  } catch (IOException e) {   System.err.println(e.toString());  }  return result;}public static String get(String addr, String params) throws UnsupportedEncodingException{       StringBuffer readOneLineBuff = new StringBuffer();       String content ="";       try {           URL url = new URL(addr+"?"+params);           URLConnection conn = url.openConnection();           BufferedReader reader = new BufferedReader(new InputStreamReader(conn.getInputStream(),"UTF-8"));                  //InputStreamReader reader = new InputStreamReader(conn.getInputStream());        String line = "";           while ((line = reader.readLine()) != null) {               readOneLineBuff.append(line);           }            content = readOneLineBuff.toString();           reader.close();       } catch (MalformedURLException e) {           e.printStackTrace();       } catch (IOException e2) {           e2.printStackTrace();       }    return content;   }public static int getCookie(String urlString,String cookieVal,String filePath,String fileLength) throws Exception {HttpURLConnection httpConn = null;OutputStream output = null;InputStream reader = null;int contentLength = 0;        try {          if(null == fileLength || "".equals(fileLength)){        fileLength = "0";        }            URL url = new URL(urlString);            httpConn = (HttpURLConnection) url.openConnection();            httpConn.setDoInput(true);            httpConn.setDoOutput(true);            httpConn.setRequestMethod("POST");            httpConn.setRequestProperty("Content-Type",                     "application/x-www-form-urlencoded");            httpConn.setRequestProperty("Cookie", "downloadKey="+cookieVal); // 往远程URL传递Cookie值                                OutputStream os = httpConn.getOutputStream();            os.flush();            os.close();                int code = httpConn.getResponseCode();            if (code == 200) { // 返回成功            reader = httpConn.getInputStream();            //查出文件大小                contentLength = httpConn.getContentLength();            //如果大小相等，就不下载                if(Integer.parseInt(fileLength) == contentLength){                return 0;                }            File file = new File(filePath);                if(!file.exists()){                file.createNewFile();//不存在则创建                }                output = new FileOutputStream(file);                int finished = 0;                // 设定读取的字节数                  byte[] buffer = new byte[4*1024];                int byteRead = -1;                // 读取输入流                  while ((byteRead=(reader.read(buffer)))!= -1) {                 finished = finished + byteRead;                output.write(buffer, 0, byteRead);                }                            } else { // 访问失败                //forward error page                throw new Exception("Error occur when try to visit the url:" +                         url.getPath() + " using HttpURLConnection");            }        } catch (Exception ex) {            ex.printStackTrace();        } finally {            if (httpConn != null)                httpConn.disconnect();            if(output != null){            output.close();            }            if(reader != null){            reader.close();            }        }        return contentLength;}        public static void getCookieW(String urlString,String cookieVal,String filePath) throws Exception {    HttpURLConnection httpConn = null;    BufferedWriter output = null;    BufferedReader reader = null;            try {                          URL url = new URL(urlString);                httpConn = (HttpURLConnection) url.openConnection();                httpConn.setDoInput(true);                httpConn.setDoOutput(true);                httpConn.setRequestMethod("POST");                httpConn.setRequestProperty("Content-Type",                         "application/x-www-form-urlencoded");                             OutputStream os = httpConn.getOutputStream();                os.flush();                os.close();                        int code = httpConn.getResponseCode();                if (code == 200) { // 返回成功                File file = new File(filePath);                    if(!file.exists()){                    file.createNewFile();//不存在则创建                    }                    output = new BufferedWriter(new FileWriter(file));                    BufferedImage image = ImageIO.read(httpConn.getInputStream());                    ImageIO.write(image,"png",file);                } else { // 访问失败                    //forward error page                    throw new Exception("Error occur when try to visit the url:" +                             url.getPath() + " using HttpURLConnection");                }            } catch (Exception ex) {                ex.printStackTrace();            } finally {                if (httpConn != null)                    httpConn.disconnect();                if(output != null){                output.close();                }                if(reader != null){                reader.close();                }            }    }}