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一个URL对象 URL url = new URL("http://www.gz135.cn/data/attachment/forum/201702/13/165605xyayykq5vy4h81vy.jpg"); //打开链接 HttpURLConnection conn = (HttpURLConnection)url.openConnection(); //设置请求方式为"GET" conn.setRequestMethod("GET"); //超时响应时间为5秒 conn.setConnectTimeout(5 * 1000); //通过输入流获取图片数据 InputStream inStream = conn.getInputStream(); //得到图片的二进制数据,以二进制封装得到数据,具有通用性 byte[] data = readInputStream(inStream); //new一个文件对象用来保存图片,默认保存当前工程根目录 File imageFile = new File("pic20170419.jpg"); //创建输出流 FileOutputStream outStream = new FileOutputStream(imageFile); //写入数据 outStream.write(data); //关闭输出流 outStream.close(); } public static byte[] readInputStream(InputStream inStream) throws Exception{ ByteArrayOutputStream outStream = new ByteArrayOutputStream(); //创建一个Buffer字符串 byte[] buffer = new byte[1024]; //每次读取的字符串长度,如果为-1,代表全部读取完毕 int len = 0; //使用一个输入流从buffer里把数据读取出来 while( (len=inStream.read(buffer)) != -1 ){ //用输出流往buffer里写入数据,中间参数代表从哪个位置开始读,len代表读取的长度 outStream.write(buffer, 0, len); } //关闭输入流 inStream.close(); //把outStream里的数据写入内存 return outStream.toByteArray(); } }