Java通过URL类下载图片的实例代码

HttpsURLConnection httpsURLConnection = null ;

         InputStream is = null ;

         FileOutputStream fos = null ;

         try {

             //1.创建URL对象

             URL url = new URL( "https://img1.baidu.com/it/u=3009731526,373851691&fm=253&fmt=auto&app=138&f=JPEG?w=800&h=500" );

             //2.与URL建立连接：首先要在一个 URL 对象上通过方法 openConnection() 生成对应的 URLConnection

             //对象。

             httpsURLConnection = (HttpsURLConnection) url.openConnection();

             httpsURLConnection.connect();

             //3.获取输入流，并创建输出流对象

             is = httpsURLConnection.getInputStream();

             fos = new FileOutputStream( new File( "test.jpg" ));

             //4.输出图片

             byte [] buffer = new byte [ 1024 ];

             int len;

             while ((len = is.read(buffer)) != - 1 ) {

                 fos.write(buffer, 0 , len);

             }

         } catch (IOException e) {

             e.printStackTrace();

         } finally {

             //5.关闭资源

             try {

                 if (is != null )

                     is.close();

             } catch (IOException e) {

                 e.printStackTrace();

             }

             try {

                 if (fos != null )

                     fos.close();

             } catch (IOException e) {

                 e.printStackTrace();

             }

             if (httpsURLConnection != null )

                 httpsURLConnection.disconnect();

         }

import java.net.URL;

import java.io.InputStream;

import java.io.FileOutputStream;

public class ImageDownloader {

     public static void main(String[] args) throws Exception {

         // URL of the image to download

         String imageUrl = "https://example.com/image.jpg" ;

         // Create URL object and open input stream to the image

         URL url = new URL(imageUrl);

         InputStream inputStream = url.openStream();

         // Output stream to save the image to file

         FileOutputStream outputStream = new FileOutputStream( "image.jpg" );

         // Read bytes from the input stream and write to the output stream

         byte [] buffer = new byte [ 2048 ];

         int length;

         while ((length = inputStream.read(buffer)) != - 1 ) {

             outputStream.write(buffer, 0 , length);

         }

         // Close streams

         inputStream.close();

         outputStream.close();

         System.out.println( "Image downloaded successfully." );

     }

}

import java.net.URL;

import java.io.InputStream;

import java.io.FileOutputStream;

public class ImageDownloader {

     public static void main(String[] args) throws Exception {

         // URL of the image to download

         String imageUrl = "https://example.com/image.jpg" ;

         // Create URL object and open input stream to the image

         URL url = new URL(imageUrl);

         InputStream inputStream = url.openStream();

         // Output stream to save the image to file

         FileOutputStream outputStream = new FileOutputStream( "image.jpg" );

         // Read bytes from the input stream and write to the output stream

         byte [] buffer = new byte [ 2048 ];

         int length;

         while ((length = inputStream.read(buffer)) != - 1 ) {

             outputStream.write(buffer, 0 , length);

         }

         // Close streams

         inputStream.close();

         outputStream.close();

         System.out.println( "Image downloaded successfully." );

     }

}

imageUrl = URLEncoder.encode(imageUrl, "utf-8" )

         .replaceAll( "%3A" , ":" )

         .replaceAll( "%2F" , "/" )

         .replaceAll( "%2C" , "," )

         .replaceAll( "%7B" , "{" )

         .replaceAll( "%3F" , "?" )

         .replaceAll( "%7D" , "}" )

         .replaceAll( "%26" , "&" )

         .replaceAll( "%3D" , "=" );

//new一个URL对象

URL url = new URL(imageUrl);