http://blog.csdn.net/sabic/article/details/6564169
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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(); } }