package getUrlPic;

import java.io.ByteArrayOutputStream;
import java.io.File;
import java.io.FileOutputStream;
import java.io.InputStream;
import java.net.HttpURLConnection;
import java.net.URL;

public class GetUrlPic {
 
 public static void main(String[] args) throws Exception { 
  //new一個URL對象 
  URL url = new URL("http://www.gz135.cn/data/attachment/forum/201702/13/165605xyayykq5vy4h81vy.jpg"); 
  //打開鏈接 
  HttpURLConnection conn = (HttpURLConnection)url.openConnection(); 
  //設置請求方式為"GET" 
  conn.setRequestMethod("GET"); 
  //超時響應時間為5秒 
  conn.setConnectTimeout(5 * 1000); 
  //通過輸入流獲取圖片數據 
  InputStream inStream = conn.getInputStream(); 
  //得到圖片的二進制數據，以二進制封裝得到數據，具有通用性 
  byte[] data = readInputStream(inStream); 
  //new一個文件對象用來保存圖片，默認保存當前工程根目錄 
  File imageFile = new File("pic20170419.jpg"); 
  //創建輸出流 
  FileOutputStream outStream = new FileOutputStream(imageFile); 
  //寫入數據 
  outStream.write(data); 
  //關閉輸出流 
  outStream.close(); 
 } 
 public static byte[] readInputStream(InputStream inStream) throws Exception{ 
  ByteArrayOutputStream outStream = new ByteArrayOutputStream(); 
  //創建一個Buffer字符串 
  byte[] buffer = new byte[1024]; 
  //每次讀取的字符串長度，如果為-1，代表全部讀取完畢 
  int len = 0; 
  //使用一個輸入流從buffer里把數據讀取出來 
  while( (len=inStream.read(buffer)) != -1 ){ 
   //用輸出流往buffer里寫入數據，中間參數代表從哪個位置開始讀，len代表讀取的長度 
   outStream.write(buffer, 0, len); 
  } 
  //關閉輸入流 
  inStream.close(); 
  //把outStream里的數據寫入內存 
  return outStream.toByteArray(); 
 } 

}