实现网络图片的下载以及信息获取

旧城等待， 2022-08-31 04:54 187阅读 0赞

## 下载网络图片资源： ##

/**
         * 获取网络图
         *
         * @param url
         * @return
         */
        public static BufferedImage downloadImage(String url) throws Exception {
            log.info("下载网络图片：" + url);
            byte[] bytes = HttpsUtils.getBytes(url);
            InputStream buffin = new ByteArrayInputStream(bytes, 0, bytes.length);
            bytes = null;
            BufferedImage result = ImageIO.read(buffin);
            return result;
        }

## 直接获取图片信息： ##

BufferedImage fileStream = ImageEditUtils.downloadImage(pic);
    int width = fileStream.getWidth();
    int height = fileStream.getHeight();

## 获取网络图片的宽高： ##

//获取网络图片的宽高
      InputStream is = new URL(url).openStream();
      BufferedImage sourceImg = ImageIO.read(is);
      int width = sourceImg.getWidth();
      int height = sourceImg.getHeight();

双核8G的服务器进行54次的循环时，会出现一下问题：

> java.net.ConnectException: Connection timed out (Connection timed out)

原因分析：程序没有关闭连接的原因，当你打开的多了，没关闭连接就会报这个错了。

**修改方式一：**

URL url = new URL(pic);
    URLConnection connection = url.openConnection();
    connection.setDoOutput(true);
    BufferedImage sourceImg = ImageIO.read(connection.getInputStream());

新问题：图片大小超过了可下载量

> org.apache.http.ConnectionClosedException: Premature end of Content-Length delimited message body (expected: 860,357; received: 524,288)

解决方式：提供关闭下载连接方式

import java.awt.image.BufferedImage;
    import java.io.IOException;
    import java.io.InputStream;
    import java.net.MalformedURLException;
    import java.net.URL;
     
    import javax.imageio.ImageIO;
     
    public class BufferedImageTest {
     
        public static void main(String[] args) {
    		
            // 图片路径
            String imageURL = "https://visionoss.wayinkeji.com/2f513628-9c77-4f5f-9634-4d69888e6459.jpeg";
    		
            BufferedImage image = getRemoteBufferedImage(imageURL);
            if (image != null) {
                System.out.println("height: " + image.getHeight());
                System.out.println("width: " + image.getWidth());
            } else {
                System.out.println("BufferedImage图片不存在!");
            }
        }
     
        /**
         * 获取远程网络图片信息
         * @param imageURL
         * @return
         */
        public static BufferedImage getRemoteBufferedImage(String imageURL) {
            URL url = null;
            InputStream is = null;
            BufferedImage bufferedImage = null;
            try {
                url = new URL(imageURL);
                is = url.openStream();
                bufferedImage = ImageIO.read(is);
            } catch (MalformedURLException e) {
                e.printStackTrace();
                System.out.println("imageURL: " + imageURL + ",无效!");
                return null;
            } catch (IOException e) {
                e.printStackTrace();
                System.out.println("imageURL: " + imageURL + ",读取失败!");
                return null;
            } finally {
                try {
                    if (is!=null) {
                        is.close();
                    }
                } catch (IOException e) {
                    e.printStackTrace();
                    System.out.println("imageURL: " + imageURL + ",流关闭异常!");
                    return null;
                }
            }
            return bufferedImage;
        }
    }

参考：[java下载网络文件的几种方式\_卞卞要运动的博客-CSDN博客\_java下载网络文件][java_-CSDN_java]

[java_-CSDN_java]: https://blog.csdn.net/qq_29976261/article/details/89839494